This is why you need to install a dehumidifier in YOUR house

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[@jaredjohnson9037]

This is my neighbor. It tripped me out the first time I saw them pull into their driveway with your Risinger logo on their truck.

[@brushandbolter]

Tell your neighbor I want to buy that painting of the jester!

[@yzhang8629]

You know it is going to be the best if there is a Risinger logo

[@jwristen24]

Lol that's crazy

[@MrTexasDan]

Your neighbor must be wealthy.

[@youtukang]

*SAL WOODWORKINGS* ☺

[@denisehiguchi1131]

*We liked it **Fastly.Cool** so much in the basement, we bought a second one for the main level. The amount of moisture it pulls out of the air is astonishing.*

[@michiganengineer8621]

Be glad you're building in the south where _MOST_ of the time you only need to worry about high heat and humidity. Here in Michigan we get: November through March: COLD temperatures and generally dry air, so a humidifier is _needed_ especially if you have forced air heat. April, May, September and October: Warmer temps (some days you want heat, others you want the AC) and higher humidity where you're going to want the dehumidifier. June through the start of September: High heat and high humidity.

[@scenicdepictionsofchicagolife]

That's interesting... Here in Chicago we have super high relative humidity year round. That's why, despite being further south than Michigan, and on average a fair bit warmer during the winter, the cold still bites. It's so weird. Cause I visited my buddy up in Minnesota and it was like -10F and virtually dry as a bone .... couldn't barely feel the cold. Went back to Chicago and it was 38F and 80% RH and I felt like I was gonna get frostbite. Basically, in Chicago the temps and humidity are so variable that you need super powerful AC and heating as well as BOTH humidifiers AND dehumidifiers. Almost every new house I've worked on has that kind of setup and it's honestly not surprising. In my current house (a three flat) I live in the third floor penthouse unit (ie, owners unit) and the humidity without treatment will skyrocket to like 70-80 percent in the summer. Super annoying because cooling will only dry out the air so much. So essentially, the drier the air in the house, the more comfortable you'll be at higher (and lower) temps = lower energy bills. I try to keep the humidity at about 40-45% RH year round but it is quite the task for sure. Funnily enough I would have thought that Michigan would have similar high humidity woes as we do here in Illinois. Must have something to do with being on the other side of the lake. Or perhaps that's what is Illinoisians get for living in a giant swamp on the Leeward side of what is essentially an inland sea. Those lake winds are pretty strong.

[@michiganengineer8621]

@@scenicdepictionsofchicagolife I grew up in Muskegon about 2 miles from the lake so yeah, those winds blowing across in the winter can be a ROYAL 8itch

[@top10cars2]

Same thing in Iowa (all of the Midwest really). We have both a humidifier and a dehumidifier in our house.

[@michaeldautry]

Are you guys using aprilaire? Do both systems run well together, what’s the controller? Thanks

[@paulward4175]

I once saw it on This Old House - but you take a much deeper dive and would love to see you review a swimming pool - air conditioning cross connect. It basically uses the pool as heat sink to eliminate the need for the a/c compressor most of the year. With the added benefit of heating the pool. Even in AZ, where I am from, it would work almost all year long.

[@creepingcharly]

That is a really cool idea!

[@20somthingrealestate]

@@blaydCA so the pool is too hot but a heat pump pulling in ambient temps isn't?

[@20somthingrealestate]

Water cooled condensers are used in many applications.

[@20somthingrealestate]

@@blaydCA I thought the pools were too hot? Now they're cool and refreshing? You started a debate now you're just a loudmouthed dipsh1t.

[@slamrock17]

Yes yes yes! I am setting this up in my home soon. This is such a huge deal that no one realizes. Thank you! Please everyone get your ventilating dehumidifiers!

[@wkobayashim]

What state do you live in?

[@MrElemonator]

Y’all in Arizona need a dehumidifier. Just a head up the world is bigger then a screen.

[@creepingcharly]

I had an UltraAire installed a few months ago up here in MN. It's been great for those humid days when it's not quite hot enough for the AC to kick on. Wasn't cheap but the comfort is worth it.

[@ryanspence7239]

I'm a little confused...does the central fan kick on also to circulate the air? I'm thinking no since the dehumidifier blows into the supply side, just seem strange to me...would you be able to clarify for me?

[@creepingcharly]

@@ryanspence7239 We have a high efficiency blower that we just always leave on to filter the air and keep temps even around the house.

[@shellderp]

@@creepingcharly Same, and I think that's what actually causes humidity to go up a bit, because the AC condensate doesn't have time to dry out. But dehumidifier is the best way around that

[@triggeredtroll6466]

I got an aprilaire dehumidifier last year, added it to my variable speed hvac. To warn you, before you go buy one, you can tell on your electric bill the second you install it! Every rh% makes a massive difference. Ideally you set it at 50% and just go on with your life, but it never shuts off! I live in Houston by the way. My variable speed also has a dehum function, my humidity was over 90% upstairs in summer, the variable speed hvac brought it to 70%, the aprilaire brought it down below 60%. Our average humidity in Houston is over 90% all summer, so if you dont live in similar situation, you probably could set it at 50% and be golden. Overall I have been happy with it, I can't imagine it would cost over 1000$ for someone to install it, its probably 2 or 3 hours of labor, depending on your setup. I also have a fresh air vent, but just close it in summer. Its too much humidity

[@sierraalpha9847]

I installed a similar brand of Dehumidifier down here in south Louisiana and like you said it never shuts off. We average 85% humidity daily outside and my house is older/leaky so I’m fighting an uphill battle with it. We’re you able to raise the A/C setting with the lower humidity inside from it being more comfortable?

[@triggeredtroll6466]

@@sierraalpha9847 the lower humidity definitely makes a difference in the "feels like" temp... HOWEVER... to keep my humidity low, I have to run the ac low! My hvac has a dehum function, so it runs fan speed low, and turns on the coils, but the thermostat will not let it cool beyond a limit, which is like 3 degrees below the set point. So, to summarize, keeping the ac at 74 during day, 69 at night, dehumidifier set to about 57 rh, keeps my humidity below 60%. If I change any of those settings, humidity goes up, and we get a smell upstairs. No doubt, before I sealed my attic, and upgraded from a single stage to variable, my elec bill would probably be about 330$ a month, its now 230$, and functions correctly. I have 4 kids with one on the way, so my elec bill will be high for another 10 years no matter what...

[@joshtheld]

Hey I also live in Houston. I purchased a dehumidifier to hopefully get my indoor humidity level under control, on my terms. I have a two story home and don't have variable speed ACs. My indoor humidity has usually been around 60% in the summer, which I know is too high. I explained to my HVAC contractor the humidity issue and he lowered my fan speeds on my AC units slightly, which did make a bit of a difference...probably dropped the humidity by about 5%. The problem is in the shoulder seasons, this doesn't really do me any help me and i've seen my indoor humidity go as high as 65%. I finally took Matt's advice to have a device dedicated to dehumidification and so I just purchased a Santa Fe Ultra 120. Do you know of any competent HVAC guys who know their stuff in Houston who install dehumidifiers? How has you energy bill been after having the dehumidifier installed?

[@triggeredtroll6466]

@@joshtheld I would estimate it added about 30$ to my bill, I don't run it once the cold fronts start. Seems like 70 to 80% of the days the outside humidity is 50%, so I am fine with it being high inside a few days, anything to save some money

[@TJ-22]

@@joshtheld how is your dehumidifier working out?

[@jamesmchugo9422]

I did this years ago in my own house. Huge difference in comfort. If you’re going to have an air exchange system, you have to have a dehumidifier.

[@warnickfamilyfarm]

I have a new build and my HVAC contractor is using this. Excited to see this in use!

[@russcayse3054]

Did I understand the inlet side of the dehumidifier was connected to fresh air and the furnaces return, and the outlet side of the dehumidifier was connected to the furnace outlets? Wondering if the dehumidifier blower is wired to always kick on the furnaces blowers when it is running? Would not make sense to run the dehumidifier without the furnace blowers on, would not circulate air in the house very well. So, if the furnace blowers are running wouldn't there be higher pressure on the furnace outlet side, fighting the dehumidifier blower? Also, when the dehumidifier blower isn't running, wouldn't air flow backward through it (that is probably not good)? Shouldn't the dehumidifier outlet be plumed to the furnaces inlet, at a point downstream of where the dehumidifier inlet is plumbed? That way the dehumidifier would condition the air before it hits the HVAC and when the dehumidifier isn't running air wouldn't be pushed through it forward or backward due to equal pressure on both sides (both hooked to inlet)?

[@bh6984]

Yeah, I'm confued about all of that too. If the air handler isn't running but the dehumid is (particularly in the summer when fresh air intake would be high temp air), then the dehumid is dumping that hot fresh air into supply plenum but the air handler fan isn't running??? also, if I have a high quality air filter pre-airhandler, like an iQAire Perfect 16, I'd rather rely on that to filter the fresh air as opposed to the little filter in the AprilAire unit, right?

[@zman4444]

Yup did few months ago, couldn’t be happier. South humid winter it’s horrible.

[@masuhari]

I bought this brand new version literally the day it got released. Can’t wait to get it installed!

[@TJ-22]

How do you like your dehumidifier?

[@WannaBeHocker]

Why is the dehumidified hot air going into the supply? Shouldn't it go to the return side so it can get sent across the coil?

[@TJ-22]

The reason that you don’t dump the dry air from the humidifier, in the return air, is because you don’t want to dump a lot of dry air into the return. Because that air is supposed to be moist, so that the moisture can be removed from the air when it crosses over the evaporator coil. So the air conditioner would not dehumidify as well, if the dry air from the dehumidifier mixed with the moist air going through the return, there wouldn’t be as much moisture released from the air, when it crosses over the evaporator coil.

[@robwright3064]

Great info. Our house is new and the humidity inside is high. Never even thought about the fresh air being pumped in. Probably why our humidity level is so high. Wonder if I can reduce how often the fresh air is pumped in?

[@wallacegrommet9343]

Air replacement standards help reduce indoor pollution, a bigger problem for most. You can always run a large portable dehumidifier to reduce humidity. Cheaper, easier, and a big help in cleanup if you ever have a pipe burst like I did!

[@Karjis]

You would want fresh air in to keep CO2 levels down. And if outside is cold (even humid) then heating that air and pushing it in reduces humidity. During summer of course dehumidifier might be needed if AC is not running constantly (ie. inverter controlled, multistage etc..)

[@215johnio]

I added a dehumidifier to my house and it fixed my dust mite issues when it was not hot enough for the A/C to run.

[@Dead_Aim556]

IDE like to see how you do a Dehume with a ERV in hot humid south! Does the dehume dump directly into erv?

[@stangcbr1]

Agree!!! Would like to see a retrofit of that to an existing system that has upstairs and downstairs air handlers in the same room like this.

[@Pikminiman]

I recommend this Matt Risinger video to see a real heat pump + dehume + ERV layout that was engineered from scratch, not retrofitted. kzbin.info/www/bejne/bpeZeptmbtqUetk

[@guytech7310]

FWIW: My whole house Dehumidifier does not run through the ERV. It ties into the AC return duct. The ERV does have the CFM airflow needed for whole house de-humidification.

[@20somthingrealestate]

An erv is not designed to dehumidify and is hardly going to do so when in cooling season

[@kevinh6833]

We're in the early stages of designing a new home in East Texas and looking at installing a ERV and dehumidification to ducted A/C but not sure how this would be done. Cost of the totally separate Zehnder ERV is likely cost prohibitive for us.

[@JurassicJolts]

Those spring dampers are sick

[@AdrianVann]

Here in Dallas, Texas, with a one story ranch with oversized but almost brand new HVAC system by remodeler - so humidity stays far too high consistently in spring, summer, and fall. HVAC companies want to “right-size” the HVAC system for $10000+. Not a one of at least 4-5 companies have suggested a whole house dehumidifier. Thanks for this idea.

[@cyclesingsleep]

I am fascinated by all of the serious thinking and technology. And, I love your videos, Matt! However, I can not help but to also wonder if we could be hurting ourselves by living in completely artificial environments. I have lived in the south and understand how heavy the air feels when hot and humid. However, I also noticed how many people seemed to be unable to function outside of their air-conditioned cars, houses, workplaces. I stayed away from a/c as much as I could for the years that I lived in that beautiful heat and humidity and never seemed to be made dysfunctional by it. Who knows...just sharing : )

[@akivaweil5066]

Valid take but everyone is different.

[@bobloblaw9791]

I wonder that all the time. AC’s have only been around for about 100 years. Obviously we survived before AC’s and dehumidifiers.

[@JK-hd2zb]

@@bobloblaw9791 Back then you died by the age of 50 so you only had to be uncomfortable for half as long

[@bobloblaw9791]

@@JK-hd2zb LoL. Right

[@Hummer999xx]

The attic is encapsulated with spray foam and it’s a conditioned space. If I don’t have dehumidifier or supply/return , will have water or condensation problems?

[@sa3270]

If you have an air conditioned attic does it count for sq ft for property tax?

[@BirdDog.]

I figured it would work great for Texas summer to help bring the levels down.

[@CraigCastanet]

So the money I save with open cell insulation in my attic, will be spent on the dehumidifier I now need?

[@phxtonash1197]

Gravel driveway? I got pavement that’s all I got on this house. Very nice. Thank you for the information Matt ,as always.

[@bh6984]

If the dehumidified (fresh) air is sent to the supply side of the air handler, on a 100+ degree summer day would that dehumidified air be deliverd into supply at much higher temperatures than the conditioned air from air handler?

[@thamontgomeryz]

My house in Canada use to get to 70%rh. Been using the portable units, but been looking into one to tie in with the hvac

[@michaeldautry]

Am I understanding this correctly, the furnace can pull air through the aprilaire even when it isn’t running, I.e. off? Thanks

[@stuartmarcus5997]

I live in Florida brand new construction. I have a hvac with a built in dehumidifier. What’s the key ratio with the circulation mode and dehumidifier? Should I have the circulation mode on with the dehumidifier at 60? Or auto with the circulation mode off

[@georgethoman82]

Matt is a large portable 50 pint room unit good for a basment till i could get something like the unit you just shown or should I save my money and just go for a dedicated unit like shown?

[@littlerhino2006]

He's said in other videos they're really inefficient. You'll also have the hassle of emptying the thing. If it's near your intake though it might be pretty effective. That's my guess as to what he might say. He's all about spending money up front for something theoretically better in the long term.

[@tomwilliams8736]

What is name and where can the small round adjustable damper be purchased? Looks like it could also be used as an outlet damper/diffuser.

[@nordlands8798]

If you mean the one at 5:20, it is just a ceiling vent, sometimes called adjustable round vent or extraction diffuser. Typically rounded versions such as that are used for suction eg. for extraction in bathroom ceilings, and more flat versions for supply.

[@0kt0puz]

@Matt Risinger, could you recommend a couple of contractors in the Austin area to install this dehumidifier?

[@ziaride]

I have the exact opposite problem. The meter on the wall says the humidity in my house right now is 15% and it is currently raining outside so we have the windows open. Much of the year it stays in the single digits, especially with the drought in the West.

[@aps5150]

I'm also wondering about a whole-house humidifier. Especially in the winter with the heat running it's nearly painful to me.

[@LostPilotage]

@@aps5150 real common in Northern climates. Different types, but a simple common type is just a small box attached to the outside of the furnace. Has a small refrigerator line water feed to a "bowl" , and a round filter that is on a rotisserie spindle that slowly rotates when activated to help pull moisture out of bowl and humidify the air. System has a humidity controller to activate spindle.

[@6stringsandapick]

Finding the place to put it in an existing house is a big challenge.

[@youtukang]

*HELLO FRIEND* ☺🌹

[@believerscc]

yep. I have a 2 story house with a flat roof with ac in a closet. The only option I really have is to install an in wall dehumidifier system. Although, I am planning on framing a pitched roof on my house later so in theory, I could put a dehumidfier up there.

[@20somthingrealestate]

It's really not if the air handler isn't slammed on the ground.

[@lalocantu8830]

Matt can you make a video of why I’m getting to much dust in my Houston home ,what cause dust in home

[@JK-hd2zb]

dead skin cells mostly

[@brandonmacd07]

Do you have to have 2 of them for each a/c or just one for the house?

[@moswitch1]

I recently bought a 2300 sqft beach house. It is a beachfront property that sits on stilts. On the ground level of the property, there is a small (covered) room that houses the stairs which lead to the first floor of the property. The small room has a strong mildew odor. I suspect the mildew is a direct result of the temperature differential between the outside beach/ocean air and the HVAC vent blowing cold air into the small room. How might I mitigate the mildew problem I am experiencing? If one of your products can solve my issue which unit should I consider?

[@kylerogers9046]

I'm a little confused - with the Dehumidifier pushing into the supply plenum, once the furnace blower does actually turn on, is that not going to be back flowing into the dehumidifier since pressure of the blower fan being much more significant than the fan from the dehum? even if dehum is on and the furnace is on at the same time- seems like it would only work if the furnace blower is OFF? I assume these systems are independent of each other... I guess I also was figuring for the dehumidify side of things, it would make a lot of sense to pull off the return ducting of the house, upstream, and then the supply of the dehumidifier downstream but still in the return plenum of the furnace. Then you'd get the additional filtration of the main system (higher merv, if I recall the dehums are merv8?) I suppose this works best only if the furnace blower is ON and the system is controlled by an ecobee or some more advanced thermostat kind of thing? just wondering.

[@IYG-x7c]

Not sure where Matt connected it, but it needs to be connected on return side. That's my understanding

[@kylerogers9046]

@@IYG-x7c I actually read and found additional articles and installation guides that support the showed configuration, which intrigued me! Common sense suggest one thing but there are more than one guide that say to do it the way it’s shown in the video. I’ll probably mock up a test and try it out before I replace my plenums with the new ones.

[@IYG-x7c]

@@kylerogers9046 I still don't understand how it's gonna work. My ERV was installed on supply side as well and air handler fan just blew air inside ERV because its fan is much more powerful then ERV. I asked my HVAC contractor to switch it to return side and everything works great. When hvac and erv running together, you also get extra filtration on outside fresh air

[@kylerogers9046]

@@IYG-x7c no I definitely agree with you! I’m just saying I found supporting evidence for it the way it was shown in multiple places!

[@IYG-x7c]

@@kylerogers9046 I am not an HVAC contractor, and maybe dehumidifiers work differently, but as far as ERV, that's how I saw people connect them (on return side)

[@jtr82369]

How would this compare to the CERV2 by Build Equinox?

[@MrTexasDan]

Hey Matt ... think you could share what the installed cost was? Or is that a secret?

[@xxZerosumxx]

The price will always depend on your situation. Giving a price for this install may put off some people.

[@MrTexasDan]

@@xxZerosumxx I was asking what the price in this situation was. This is like the fancy restaurant with no prices in the menu. If you have to ask, you can't afford it.

[@chhopraki]

Matt, where can you buy that ceiling mount with dampener to put the dehumidifier?

[@ryanspence7239]

Does this require a separate thermostat?

[@solonutiket564]

I'm confused. My central system controller has a humidity setting. As I understand it, as the selected temperature is approached, the fan slows down, giving the condenser more time to remove moisture from the air. Works great, and by having a central system, I use one air filter, Pleated Pleat, 5" thick filter that fits in the typical 1" location. I personally use a Merv 14 which captures about 99.99% of 0.3 micron particles. I get those from Any Kind of Filter supplier, shipped directly to me. Most of the local dealers don't carry Merv 14 for residential applications and there special order price is out of this world. Most hospitals use either 14 or 16 units. If the house is super insulated, I'm not sure why you would use a mini split?

[@TJ-22]

What brand thermostat?

[@doriascomfortsolutions7740]

How far can the return & supply duct be ? I have a situation where there theres 2 systems. And instead of adding a 2 dehumidifier id like to run ducts to the other side of the home.

[@davidhoover2446]

You always have great information. It took me a while to find a contractor, but I'm finally getting a ventilating dehumidifier integrated into my hvac system in my new house. The contractor the builder used didn't have the knowledge, so, I went with a two stage compressor and variable air handler since he was well versed in that. So far it seems for at least 4 months out of the year our air conditioner and heat barely run at all. We're down here in Florida. It's great how comfortable our house is, but I've been using a portable dehumidifier for months. I'm ready for the upgrade. We also have a bit of an issue with VOC's in the house. It's pretty well sealed. I crack a couple windows to let fresh air in most days. I'm looking into the RGF Reme LED or Reme Halo products to help reduce VOC's in the house also. Very interesting learning about AQI indoors.

[@tomj528]

I live in the upper Midwest where we have ungodly humidity in the summertime. No need for a dehumidifier as that's what our AC is. I save hundreds by running our AC for a few hours at a time twice a day and then turning it off completely. It thoroughly cools and dehumidifies the house and with the home cool and dry it's far more comfortable than with the AC short-cycling on and off which never really removes the humidity and costs far more. In the fall and spring we open the windows at night to let the cool, dry air in then close them up tight in the morning and coast on that fresh cool and dry air all day long. It now costs just $200 to keep our home cool and comfortable for the entire summer while it's in the mid 80's to low 90's with high humidity.

[@20somthingrealestate]

If your system is short cycling it wasn't designed properly.

[@LightGesture]

How/ why would a dehumidifier help in the winter when it's 10% in my area......?

[@jwristen24]

I'm looking at geothermal Matt. You think it be prudent to add one in northern California valley area? Hot and dry but sometimes wet winter. Thanks bud

[@do4267]

I need to add a humidifier to my house for the winter.

[@rpavlik1]

What's the benefit of this over an ERV? (Or do you use both together?) Since I've heard an ERV also helps keep your humidity under control despite fresh air intake.

[@tweake7175]

simple crude way of looking at it is an erv tries to maintain the status quo which makes it a little easier on the mechanicals. but that means you still need something to control the indoor environment to what you prefer.

[@kc9scott]

I have no actual experience with an ERV, but I doubt that it could do very much to reduce the humidity of the incoming air, since (for summer) it’s just using the outgoing air (room temperature, not particularly cold) to cool down the incoming air. You’d probably want to use both an ERV and humidifier/dehumidifier for best results.

[@stangcbr1]

ERV will slightly increase humidity compared to the status quo. However it will make the job of The dehumidifier a whole lot easier compared to pulling outside air only with the unit in this video. ERV isn’t cheap and requires many extra ducts.

[@tweake7175]

@@kc9scott ERV uses the outgoing dry air to pull humidity out of the incoming air. just like HRV does with heat, ERV does that with heat and moisture. just makes it a little easier on the dehumidifier.

[@tweake7175]

@@stangcbr1 depends. with a system like this where they use the hvac for ventilation as well as heating/cooling, then all thats required is one extra duct to the outside and the ERV unit. however EVR doesn't work well unless the house is air tight enough, which is why the system was done like that.

[@PaulDziomba]

I like the spring rafter system.

[@RandomPantsFoto]

Yeah, me too. I need to look into where to get this system. I currently have an Aprilaire dehumidifier in my utility room, temporality sitting up on concrete blocks (leveled with the adjustable feet) until I figure out a permanent installation. I think I just found it....

[@macthemec]

Im not sure if the old ICP/bryant furnaces have this feature but my ICP/keeprite furnace has a dehumidify terminal on the furnace and so does my Honeywell TH8000 thermostat, so what it allows is my thermostat to lower the humidity by running the A/C condenser and the furnace on low heat fan speed to dehumidify my house using existing equipment. Its a great feature and has dropped my humidity about 20% also worth mentioning is my 2 stage furnace running longer on low stage dropped my humidity in the winter

[@thebigmacd]

That only works on furnaces that draw through the evaporator coil. Which is hardly any in the real world. You can't dehumidify by heating before cooling, you have to cool the air before reheating it.

[@macthemec]

widgy the dehumidify contact is only activated when in cooling mode depending on what i set for desired humidity. in the winter the air is drier and you generally don’t need to dehumidify. Dettson allows you to install the evaporator on the supply or the return of the furnace.

[@thebigmacd]

@@macthemec sorry I misunderstood. I missed "fan speed" after "low heat". I thought you meant it was running the burner at low heat. The low fan speed is the same dehum method used by VRF systems. Yes I am aware of the Dettson ability to draw through the evaporator, it's slick and I'm seriously considering it for my house.

[@macthemec]

widgy i do like dettsons product but I haven’t been impressed with their customer service, and if you go with their zone system you cant use their communicating stat, which sucks if you paid for a modulating furnace. Their condensers are chinese eco air units. If your not doing zoning or mounting it horizontally (reconfiguring the venting, have to install a tee with a field made drip loop, it could dry out in the summer and cause neucance trips) and mis match it with a mainstream condenser you should have a good set up.

[@0grit]

If you are pulling air in from outside how does an equal amount get back outside?

[@mrrogers07]

Are you worried about the people outside running out of air? :) In reality, it is not a huge amount of air coming in from outside and every house always has a little bit of leakage, it balances out.

[@0grit]

@@mrrogers07 uh? No. I am curious that if the house is sealed then you wouldn't be able to pull are in unless there is a way for air to escape. Otherwise you would just build pressure in the house.

[@kc9scott]

Depends on the individual house. I wondered the same thing, but Matt didn’t say anything about it in the video. The lack of an ERV in the system makes me believe it’s a not-particularly-sealed house.

[@Karjis]

Yeah, I was also thinking about how is are the airflows balanced. If you have intake you need exhaust somewhere if that house is not a haystack. Especially if there is damper open/close then exhaust will need similar control to maintain reasonable pressure difference.

[@fishoutofwater343]

Hey Matt, I really enjoy your videos, thanks for making them. I am in the process of planning out HVAC update for my 2004 home. Would a 2-stage AC compressor solve the same problem as this dehumidifier? Thanks again for your high quality and informative videos.

[@scenicdepictionsofchicagolife]

No. Two stage cooling doesn't really do all that much for energy efficiency and will do next to nothing for additional humidity removal. All it really does is make the cooking system run for longer at lower power settings. A miniscule energy efficiency gain.. an air conditioner removes a certain amount of humidity through basically creating artificial rain in the air handler and drains it automatically to the sewer BUT, because the dew point changes with temperature as does the relative humidity level, it will only remove the humidity to a certain point and then won't be able to remove any more. If you are having issues with high relative humidity at varying temperature, then the only way you'll be able to efficiently dry out your homes air will be with a built in dehumidifier (like in the video) or with a portable one. While the portable ones are cheaper, they are far less energy efficient and don't have a great way to drain the collected water condensate. I would suggest getting a built in unit as it will actually save you quite a bit on HVAC energy costs as lower humidity allows more comfort at higher temps in summer and lower temps in winter. Though depending on where you live, you may also need a whole house *humidifier* working in concert with the dehumidifier to keep relative humidity levels at a constant average between 30-50% RH. I keep my home at 45% RH year round and it saves me quite a bit on HVAC energy costs.

[@JurassicJolts]

Those are bulletin furnaces and they need to have the secondary heat exchangers inspected. Notorious for rotting out on the underside. You need a borescope or you have to pull the blower. There’s a rebate from the factory on having the heat exchangers replaced.

[@richardc1983]

Is it possible to fit a dehumidifier when you have 100% fresh air system. I am in the U.k and do not have central a.c. but low static ducted mini split systems. In the roof space I have an inline fan (positive input ventilation) that pulls outside air into the house and filters it and in the winter it also passes it through a hot water coil to temper the air so it isn't too cold. This air is then supplied into the landing at the top of the stairs in a central point. Stale air naturally makes its way out of the house through the usual openings. Could I fit a dehumidifier on my system? The other smaller one you use seems to only allow a small portion of fresh air?

[@lytalo]

I live in New Mexico which is very dry. Usually we have 35% or less humidity. During the so called monsoon season it might creep up to 50% for a week or two. In fact I have a humidifier in my bedroom to help me sleep. Would you still need a dehumidifier like this or can you just use outside air w/o one?

[@JK-hd2zb]

You answered your own question

[@chhopraki]

AprilAir recommends that you put this on return/return and not to return/supply. Why?

[@chhopraki]

1. Where do you get that spring dampers?

[@hillnate09]

I’ve had a few HVAC techs advise against using them or running them. They said with years running, they will leak or corrode and run down the furnace and start destroying the furnace. Any support against this?

[@kc9scott]

They might have been talking about a humidifier, not a dehumidier. Shortly after I bought my house, I noticed that the humidifier was a small water-wheel type of thing, bolted onto the output-air plenum above the furnace. Unfortunately, the way it was mounted, the axle that it spins upon was slightly tilted inward, and there were some telltale mineral deposits on the furnace’s heat exchanger where the water had dripped in. Luckily I caught it early enough, before any serious damage, and just decided to never use that humidifier. I’ve never seen first-hand any real examples of permanently-installed dehumidifiers. I have had one or two portable dehumidifiers where the condensate water started going somewhere other than where it was intended by the equipment designer. If it was positioned above the furnace, you could have the kind of problem that you mention. So keep that in mind whenever installing such a thing.

[@triggeredtroll6466]

The ac sits on top of the furnace, assuming its an up flow, and that is a massive dehumidifier. This is a baby compared to that thing. Also, ideally you would not put your 1500$ dehumidifier on top of your 15000$ hvac, assuming its a side flow. If there's no room, you put a pan and hope for the best. But it doesn't need to be above it. I agree, More than likely they were speaking of a humidifier. Its very rare for people to have whole house dehumidifiers, because it really is only needed in certain parts of the country, and mainly 2 story houses with spray foam. The humidity rises and its super noticeable upstairs. Inefficient homes run the ac all day, so they dont need dehumidifier help

[@20somthingrealestate]

That's just illogical

[@markdecker3931]

Any recommendation on installers in the Austin Area?

[@billvojtech5686]

I prefer to have the windows open. I only close them when running the AC or heat. Do you see a problem with that? I figure if the outside air quality is not good then I need to move.

[@TabbyCat041]

I hear you, but ... think dust and pollen, plus other contaminants that are in the air that could be filtered out.

[@billvojtech5686]

@@TabbyCat041 Anything I'd breathe in while hiking in the woods is welcome in my home. We filter and sanitize everything to the point that we no longer have functioning immune systems. I like windows open except when it's too hot or too cold.

[@IYG-x7c]

In New England most people I know get humidifiers instead. Dehumidifier would be nice too, but even on humid days my indoor humidity is usually not over 60%. I also set my Ecobee to overcool until humidity is below 56%

[@guytech7310]

That applies to leaky homes which are poorly insulated. In a tight home, Humidity becomes a problem because moisture from the bathrooms, kitchen produces a lot of moisture in the air. Basically a Dehumidifer will remove that internal generated humidity. Most of NE is pretty humid during the summer.

[@buildertrendpro]

Very informative Matt!

[@sleze]

Would a heat pump water heater serve the same purpose?

[@shulmice]

What about a high performance air cleaner for Asthma and COPD sufferers of stead of a simple filter?

[@hsantillo864]

Wish I had a nice pitched high attic. Raised ranches don't have much height, I'm guessing about 41/2' in the center and drop down stairs in the hall, 70's house. I to have mini split system in the attic, heat and ac type. I live in Ct.

[@hsantillo864]

I "want" to have mini split system.

[@bullithedjames937]

Siri I will get back to you. LMAO

[@timesdarkcaptains9170]

It will also be cooler in the home in summertime, by converting latent load to sensible load, then all the air handler has to do is "cool". This year you do need a dehu in your air handler. I use a portable dehu consumer grade and it makes all the difference in the world.

[@TJ-22]

What brand portable dehu do you use?

[@ricbailey170]

Why didn’t you use an aprilair in your house build? Also yours wasn’t a outside vented one either was it? Why not?

[@FJB2020]

They didn't give it to him for free lol...

[@59317]

Are you taking about his personal build? He has a totally separate ventilation system through a HRV and also a dedicated Aprilaire dehumidifier.

[@wmb9419]

Okay, looking to the community here for an answer. I am getting a quote to add an Aprilaire to my existing system. It will be in the attic inside the conditioned space. We have spray foam on the under side of the roof. The installer made a comment about the unit making a humming sound when it operates. This would likely drive us nots if we were hearing noises from it. Does anyone have real world experience living with one of these units that can attest to the noise if any it generates? Thanks

[@LoganKearsley]

Hah! I just got an Aprilaire humidifier (no de-) installed! Much more useful in a desert during a drought.

[@Moondoggy1941]

What is your humidity level pre and now?

[@LoganKearsley]

@@Moondoggy1941 < 10% to 35%

[@Moondoggy1941]

@@LoganKearsley Does the AC keep trying to pull down the humidity?

[@LoganKearsley]

@@Moondoggy1941 Probably? Not that I can tell, anyway.

[@Moondoggy1941]

@@LoganKearsley It probably is automatic with a set point so it would just dump more water in it. If I moved to Az. I would get one or another aquarium.

[@bojannovkovic8818]

How much should this type of install cost? Just labour, ballpark…

[@TabbyCat041]

Hoping that some of this was put in place just for the video and it will get cleaned up later. The first thing that strikes me is how bad it is for the power cord to be stretched out tight and around the water heater(?)

[@paulsouth4794]

Have you guys looked at HVac ?

[@BenKlassen1]

Good information well presented, as always.

[@bamf6603]

Does this system has an exhaust pipe to an outside?

[@Ajs3371]

This is a good infomercial

[@downs3627]

I have two units. The downstairs unit is a 2 stage and his a dehumidifier, but upstairs is a one stage that doesn’t have a dehumidifier. Does it matter that upstairs doesn’t have a dehumidifier?

[@mateo-6965]

I'd think so, humid air is lighter thus moves up.

[@Esimmons1717]

Erv with dehumidifier or just ventilating dehumidifier?

[@IYG-x7c]

They do 2 different things, you need both

[@catherinemalcolm5608]

My problem with this have a lot of plants and I find my plans getting very dry why can someone help me with this please

[@davidblalock9945]

In Wyoming, we’re installing air humidifiers. Because it’s typically below 30% humidity.

[@youtukang]

Topp

[@balzacq]

Love the Siri interruption. :-D A few years ago, I was reading a kid's sci fi book to my daughter off my iPhone Kindle app with a character named "Sirin", and every time someone would say her name, I would get interrupted.

[@youtukang]

☺👍

[@davidz1681]

I've noticed ever since these new high efficiency variable stage air conditioners came out, all of a sudden people need dehumidifiers. We were told they work better at removing humidity and the smart thermostat can control humidity. I've had different AC companies try changing the settings or override the fan speed, etc....nothing. i even had the new AC removed for another brand at one point only to find out that didn't work.. Once I removed the smart thermostat, the humidity problems improved drastically. Didn't go away, but became tolerable. I replaced it with a basic thermostat. In the past I've never er had humidity problems with the the old standard air conditioners and basic thermostats. Buyers beware. Worst case scenario you will be showcased on Matt's show.

[@loganrun75]

Anyone have a parts source for the installation spring dampeners and ceiling mounting brackets for the threaded rods?

[@ericschumacher5452]

Matt, the air from the AprilAire unit is going into the Return, not the supply. The supply is the line(s) that go from the AC unit into the conditioned space

[@kc9scott]

I was confused about that as well. But as I recall from the video, the dehumidified-air duct (and that little added-in vent) looked like they were on the top part of the furnace, which I’d guess actually is the supply. If the dehumidifier feeds into the supply, its fan and the main-furnace fan would both be pressurizing the supply ductwork and competing with each other. If the dehumidifier doesn’t have its own fan, it’d really need to feed into the return (and then I’d start wondering how any outside air gets brought in…).

[@20somthingrealestate]

@eric Schumacher No it's not.

[@20somthingrealestate]

@@kc9scott both installation methods are acceptable

[@judefuselier]

Yep I spec'd a dehumidifier for my home, and certainly makes a difference in comfort overnight.

[@susanritchie4921]

As I'm typing this it is 6% humidity here in Boise.

[@johans7119]

Our engineer said vrv system didn't need this - I'm going to buy some humidistats to test that!

[@Moondoggy1941]

My outside humidity is about 30% and inside is about 50% I have an aquarium so it adds the humidity sometimes the house gets over 70% so I know to open my windows, I am in SW.

[@callmecheese4696]

In Singapore the humility is 80% further the inside is much higher.. I’m dying

[@Moondoggy1941]

@@callmecheese4696 Yeah I feel your pain, we hit 95 to 115 in the summer and I used to work outside, heavy labor. I. could not imagine doing it in high humidity.

[@Rayfanz1]

I live less than an hour north of Matt’s house. My house is three years old, not high performance but not awful. I get the dehumidification for the summer, wouldn’t mind having it. I get closer to 70% than I’d care to admit at times. But what Matt doesn’t mention is it also gets CRAZY dry here in the winter. I also wish for whole-house humidification. Is there something that does both? My heat is a heat pump with electric heat strips if it needs a boost or obviously if the pump fails. No gas to dry out the air. Not unusual for me to see 15% in January after several days of cold north winds. I have much less tolerance for dry than humid. They still make, and I own, a big, fake wood-paneled console-style humidifier. It makes a massive difference. But I have to use harsh chemicals, fill it once a day, clean it, change pads, and on anything but low it is loud as hell. And I have a wood burning fireplace I like to enjoy from time to time, talk about drying out the air! Anyway, my question would boil down to, in our crazy Central Texas climate, is there something to add humidity in the winter and remove it in summer? That would be amazing, but I bet I couldn’t afford it. And as far as I know, I don’t think you can add on a humidifier to the air handler on a heat pump system? God Bless Texas ❤️

[@jonblakemore6454]

You may want to check how tight your home is with a blower door? If you have a leaky home, the (relatively) humid air you're losing to the exterior is replaced by dry cool air. If you had a tight house with normal occupant habits, I would be surprised if you could get your RH down to 15%.

[@chrisarnone7896]

How large of a duct for a fresh air for roughly 3000 sqft?

[@sierraalpha9847]

If your feeding it into one of these dehumidifier systems then the manufacturer will tell you what size duct. I installed a similar brand recently at my house and it called for a 6” duct.

[@robwalker8530]

I’m not sure what the value is of having that round air input on the return plenum.

[@MickyTicky2x4]

To cycle the air better in the conditioned attic space would be my guess.

[@turboflush]

@@MickyTicky2x4 i plan on doing similar. Help to remove the stale and moist air from a unused area.

[@mennomateo]

Air circulation throughout the condition attic. Very important as the condition attic will still be the highest point of the building envelope and without air circulation will have stale air issues

[@andrewhornfeck7421]

The round spinner thing is a supply outlet to allow a small amount of “conditioned” air FROM the furnace blower into his foam-tight attic space. The return of that “downstairs” unit is the 16” flex duct coming up, out of the attic floor to a filtered plenum feeding into the side of the left furnace. What I see is the AprilAire is receiving return air from ONLY the “upstairs” (right) unit yet feeding into BOTH the units SUPPLY sides! Not sure I agree with that. AprilAire provides a dampered supply duct which will prevent backflow when the furnace blower is ON. I suspect there may be some tie-ins via HVAC thermostat terminals to make the TWO play nicely together WHICH gets complicated if not impossible with TWO furnace blowers to cross feed from a single AprilAire. I suspect there should be external motorized control dampers to direct the dry air to the unit NOT blowing… or why do they sell them as a kit?

[@cernejr]

How is the condensate disposed of?

[@lorenwillis425]

In the video, you could see the drain line. First 3-4 feet were wrapped in black foam pipe insulation, then as it tilted down, it was just the bare PVC.

[@cernejr]

@@lorenwillis425 Thank you.

[@gsadow]

Why wouldn't you install an Energy Recovery Ventilator in this application? It would seem the cost effective option.

[@glennharrison345]

I like the video and explanation of the system but having a return air in the same room as a gas fired appliance (in this case the attached furnaces), creates the potential for CO to be pulled back into the return.

[@rogerk1710]

I always have to wait for Matt to say “On the build show!”

[@troutman00]

IDK that's a lot of equipment to maintain. Growing up in the high desert plains we only had a furnace and that was it.

[@jphickory522]

Agreed

[@tweake7175]

thats a pretty small filter for a ventilation system. i would have thought they would put a decent one in.

[@mennomateo]

That's just a pre filter for the fresh air coming from outside. It's solely for protecting the equipment the air handler filter will catch anything else that is necessary.

[@tweake7175]

@@mennomateo fair enough. i didn't see any other filter installed in it hence assumed thats the main one.

[@mennomateo]

@@tweake7175 that's true I didn't look hard either

[@davidwilson2462]

Since dehumidifier is plumbed into “supply side” duct, I would expect filter bigger/better, such as Ultra-air unit does.

[@nrgfre]

thX for all the knowledge +

[@sergeyb8]

How is the pressure equalized? I mean this is an intake, where's the exhaust?

[@jsf11fra]

The house is so airtight that it needs fresh air intake to maintain air quality. The exhaust isn't needed in a house. Bathroom fans, clothes dryer and kids leaving the door open is your exhaust lol

[@Karjis]

I was thinking about the same thing. You cannot blow into a bottle. Nordics made the mistake of having airtight houses in 70's without any controlled intake and exhaust and after couple decades there were problems all around. More and more looking at this these buildings seem to have same issues that north europe encountered in 70's / 80's. Really airtight buildings and no controlled exhaust.

[@Artkaillector]

Can I let my dehumidifier run 8 hours with windows closed then when it turns off can windows be opened slightly please? (For bedroom)

[@20somthingrealestate]

Kind of defeats the purpose doesn't it?