Build a HVAC WIFI Monitor for $50

This is a step by step tutorial of how to build a very affordable HVAC Wi-Fi monitoring system.
#airconditioning #heating #homeperformance #hvactraining #bluecollar #buildingscience #comfort #hvac #hvactech #betterhvac

[@jeffbrown6579]

This channel should have 100k+ subs. Tim, you do an outstanding job of explaining a build. I watch several home automation channels, some of which use Shelly modules and I've never seen anything quite this cool and useful. Spread the word, people.

[@timdestasiohvac]

@@jeffbrown6579 wow thanks!

[@aleonyohan6745]

I'm an industrial refrigeration technician. This video is absolutely phenomenal. I have been looking for HVAC remote monitoring. And those Shelley devices are amazing. Thank you for this video. You did a phenomenal job

[@timdestasiohvac]

@@aleonyohan6745 thanks

[@ugbundominations2007]

Really great content. Consider adding affiliate links in the description for all the products. I like to use them because 1) I know I’m ordering the exact product used and 2) it helps you as the content creator. Super cool and keep it up!

[@timdestasiohvac]

Thanks

[@marconantel7735]

I came here to say the same!

[@timdestasiohvac]

@@marconantel7735 thank you

[@marconantel7735]

@@timdestasiohvac I ordered all today, added humidity sensors, not sure about incorporating them, we’ll see when they get here!

[@timdestasiohvac]

@@marconantel7735 only one humidity sensor can go on a Shelly plus one. So you'll need to have two. That's what I am running on my home system permanently. I will be releasing a video soon about it. A few more components and sensors but it gives a lot more information. Stay tuned.

[@philiplashley7888]

Just Awesome - been searching the Internet the past 3 months trying to find such a device that accurately measure the Return and Supply Temperatures in our Home HVAC… This certainly will get the job done and more…Thanks!!!

[@timdestasiohvac]

@@philiplashley7888 I will be making a video about another setup that includes humidity

[@ProleDaddy]

​@@timdestasiohvac Fantastic. This is great stuff, bro. Thanks.

[@xincai951]

@@timdestasiohvac Hello. Just wondering if you are done with the video setup that includes humidity as well. Thanks.

[@timdestasiohvac]

@xincai951 had to take a break from it to catch up on work. Might be in December ir January

[@xincai951]

@@timdestasiohvac ok thanks.

[@Xdonald331]

Great video! I’ve thought of something like this, but I’d like to monitor static pressure to know when it’s time to change the filter!

[@timdestasiohvac]

@@Xdonald331 stay tuned

[@alanbarber4543]

This is perfect! Just the other day our AC stopped cooling due to a clog in the condensation drip pan drain caused the float switch to turn off the chiller. Was just thinking of setting something else to monitor the temps and float switch!

[@matts1196]

Thanks for posting this! I just completed this project following your instructions. I did use the fifth temp probe for an ambient temperature, may as well since they came in a five pack! I appreciate the precise instructions and details! I also tied the Shelly into Home Assistant and created a dashboard for the HVAC monitors, including controls for the thermostat. Placed an old tablet on a mount near the HVAC unit to display the stats. Maybe that will help keep the HVAC maintenance guys from pin cushioning my return and supply ducts to measure temp each visit. 👍

[@timdestasiohvac]

@@matts1196 yes if you can snake a wire outside, then go for it!!

[@rwojo]

Great to see this, did something similar with the addition of using a Shelly i4DC instead to monitor the HVAC lines themselves (cool/heat/fan calls). Something I didn't make the leap to is to utilize Sensirion digital pressure sensors to measure pressure drop on the filter, but man they are expensive and would take a bit more work to integrate with the pitot tubes. Instead I opted for good-ole analog Dwyer Mark II mamometer, which seems to work really well.

[@xphiles2345]

ooh i love this, metrics!!! as a sys admin i like. and the fact it shows you how to make it is nice. ill be saving this video. ill be flashing this with tasmota and integrating it into my openhab system.

[@timdestasiohvac]

@@xphiles2345 🙌

[@RickEstrada]

lol I made this almost exactly a few months ago and integrated into HA 👍🏻 good walk through, I didn’t do the line temps but gonna add that asap!

[@shrdinc]

This is awesome - never knew this company existed, while normally you can do many of these things with an arduino without the “server side” it’s tough once outside your network. Wish they made a unit with more channels. Just got two complete setups for monitoring a chilled water cooling system on a boat! And another to just use as a flame out indicator for my smoker!

[@timdestasiohvac]

That’s awesome. Shelly does make a 3 relay pack.

[@andrewsegner468]

Would that work for 3 wire humidity or enthalpy sensors as well? How about expansion capabilities? That's really clever, great job and video!!

[@timdestasiohvac]

@@andrewsegner468 there is a separate analog input for those sensors. And there is no limit to how manu sjelly devices can connect to the same account and create automations for them.

[@PowderMill]

Great video … Thanks! Btw - when you mention drill a 1/2” hole for Romex/NM cable connector, many viewers might not be aware that 1/2” is the “Trade Size”. The actual physical hole should be 7/8”. Thanks again… Btw - there is a small device (see NICS alarm KZbin channel) that has a no or nc dry contact input and will send you a message via SMS/text. It uses Wi-Fi and is around $15 I use a float switch to alert me when/if the “emergency” pan under my attic fan-coil unit. It alerts me prior to a wet 2nd floor ceiling. I will eventually add a relay (NC) inline with the “R” 24vac thermostat feed to kill the A C if the condensate drain is clogged.

[@timdestasiohvac]

You can do the same with the add in- it takes digital and analog inputs. But yes thank you, it’s a great time to be a tinkerer!

[@PowderMill]

@@timdestasiohvac Thanks for a bingeworthy channel!

[@nubus1987]

I had this on my hvac for about a year and it works great :)

[@Usernotloggedin]

Pretty cool...no pun intended. I did similar with an Arduino some yrs ago but with exceptions. I thought I could sell it as a remote monitoring system to local HVAC companies. An early warning system of sorts to alert HVAC co's before their customers saw a problem. My system included a couple pressure transducers on each line as well as temp sensors. I included a wifi module & system voltage sensors as well. It worked pretty well with my home system. Much like a FieldPiece gauge systems does. I found my local HVAC co's weren't interested in this so I gave up. It's nice to find that I wasn't alone in my madness lol.

[@timdestasiohvac]

A few companies, namely Emerson failed with this too. Sensi Predict had so much potential but never got a foot hold. But there are always a few companies out there that would totally use this to offer better service. But it doesn't fall into the typical model of sell sell sell that most HVAC companies do.

[@jasonsachinger3276]

Can you share any of the components you used?

[@timdestasiohvac]

@@jasonsachinger3276 I actually did include them in screenshots.

[@jasonsachinger3276]

@@timdestasiohvac Yes you did thank you! But I was replying to @Usernotloggedin comment about his project. I'm curious what fittings and probes were used to do the inline measurements.

[@timdestasiohvac]

@@jasonsachinger3276 i just strapped or inserted the sensors. They are ds18b20 universal temp probes

[@hjc4604]

Is there any info on the other things you've got hooked up to your air handler? Looks like some interesting stuff!

[@timdestasiohvac]

@@hjc4604 yes! Look back at my feed!

[@memsu06]

I do HVAC controls and this is exactly something I've wanted to do to my house unit without using some commercial controller.

[@timdestasiohvac]

@@memsu06 youre gonna love my temp/ humidity/ airflow one Im building!

[@gregmead007]

Very cool! (Pun not intended) I’ve been looking for commercial products that could do this but they were all either unusable junk or very expensive. I was exploring an Arduino based solution but this is so much cleaner and has an app already built. Thank you!

[@marylegz90]

Glad I ran across your video, thanks! I just got my first Shelly devices in for another project, but now I need to order the Plus 1, Addon, and some temp sensors! One thing I would add is a condensation float switch into the Digital Input. The Analog Output could also control a 0-10v outdoor/fresh air damper, as well.

[@timdestasiohvac]

@@marylegz90 you will need another add on for a float switch i believe. I power mine after the existing float switches which will tell me its tripped via power/ comm loss

[@marylegz90]

@@timdestasiohvac - On the add on module Shelly’s site states that it had a digital input. This should be able to be utilized for a float switch for condensation overflow or for a CT for fan status. Am I reading the information wrong? Mine comes Sunday, so I’ll play with it then.

[@timdestasiohvac]

@@marylegz90 yes, but im not sure you can add the input to the temp sensors.

[@marylegz90]

@@timdestasiohvac - Just following up on this. I successfully got my 1 Plus setup with the Add-On module. I’ve got (5) DS18B20’s wired into it as well as a condensate float (could also do a fan switch) into the digital input (GND and Digital terminals). It will turn off and on based on the switch input being open or closed.

[@timdestasiohvac]

@@marylegz90 this is awesome!

[@TimGray]

I skipped the power box and wired the shelly directly to the 24V my air handler generates for the thermostat, it works great.

[@timdestasiohvac]

Interesting- good to know. Did you wire the Shelly the same way or what input voltage config did you use?

[@ZWBenedict]

KZbin recommended this video to me and I'm glad it did. I'm a huge fan of home assistant and data tracking. I currently have Temp/humidity sensor in each room and I track the power draw of my hvac system and compare performance that way. What are the benefits of knowing this data? What sort of analysis could a residential home owner do on this data to know how the system is performing? Thanks so much for posting. I'm ordering parts as we speak!

[@timdestasiohvac]

Shelly works well with HA from what I know. As far as analysis, there is not any yet as I know. That's my next project to learn. Thank you!

[@ZWBenedict]

@@timdestasiohvac Shelly works great with Hass! I ordered the temp probes you used and plan on hooking them up via ESPHome. As for the analysis, what sort of data are you looking for when monitoring the 4 sensors? Are you just looking to make sure the output is cooler/warmer than the input? What else am I looking for once I have the 4 data points?

[@timdestasiohvac]

@@ZWBenedict You're looking for a temperature difference between Supply and return of at least 15-25 degrees. Liquid temperature should be around 10 degrees above outdoor temp. Vapor line temp in cooling mode should be between 50 and 60F. If it is a heat pump, the Liquid temp should be around 10 degrees above the return air temp and the vapor line temp should be round 30-50 degF above the liquid line temp.

[@williammiller7543]

@@timdestasiohvac Thanks for this great response, It doesn't do us any good to know Data Points if we don't know what they mean and how this info can be used. Thanks

[@mechanicalenvironments]

Great idea! I can definitely think of a couple uses for this.

[@jackpestaner6925]

Nice job, I played around with the same system, but my challenge now is to detect condensate overflow in a mini-split. I need to find a leak detection module that is low cost...

[@timdestasiohvac]

@@jackpestaner6925 a float switch can be tied into a digital input on the add on.

[@jcook69camaro]

according to your return and supply temp you either have a dirty evaporator coil, dirty air filter or you not moving enough air. delta T should be between 16-21 degrees.

[@timdestasiohvac]

@@jcook69camaro most of the time yes. But my Bosch compressor algorithm was making the compressor ramp up at that particular moment. I can assure you that everything is clean in my unit. Stay tuned for more videos.

[@hjc4604]

Great video ! I was looking at the Emerson Sensi Predict but then it disappeared. I figured it didn't sell like they hoped, even with MeasureQuick hyping it. I see MeasureQuick started monetizing. Not unexpected.

[@timdestasiohvac]

Hi, and thank you. Yes, I was disappointed in Sensi being cancelled too. I've talked about this to other industry people and there simply isn't as much of a demand for this in residential but I think there is one in commercial. MQ was always monetized but the took away screen shots last year unless you buy Qbits. I still buy Qbits even though I don't really use MQ's reporting. I just build the $5 each unit for an entire year into my pricing. No MQ is in with Smart AC but the data you get is very limited and it doesn't catch the performance problems with units like they say it does. And it's battery powered so sooner or later the batteries will die. I'm not impressed.

[@CubbyTech]

Curious if the 24vAC transformers in the furnace output enough current for the extra load. I can't believe how inexpensive the temperature probes are! Please consider doing another video showing us what to look for - potential problems, etc...

[@timdestasiohvac]

Yes I will. I am currently running 3 Shelly Plus 1's off the same transformer as my HVAC system. But adding a transformer and a fuse isn't a bad idea. Thank you!

[@eljefe62]

Nice. I've been using a combo of Raspberry Pi & Arduino units to monitor my system. I have an outdoor pellet furnace and it has built in monitoring via web, but there's no way to control anything remotely. This system looks much simpler and easier to setup. My only critique is on the enclosure...use cable glands rather than a romex connector at least they are water/insect proof as well as easily obtained at Lowes/HD type places.

[@timdestasiohvac]

@@eljefe62 my next version will have grommets stay tuned for that video

[@manusengelbrecht9959]

Great Vid, Maybe get some boot lace ferrule for the cables, will neaten them up more and also provide some protection against a possible short.

[@timdestasiohvac]

@@manusengelbrecht9959 this was a temporary setup to test it on my unit. The controls that you see behind it are all carefully wired and secured.

[@linearburn8838]

if your using it at home home assistant and tasmota is da bomb

[@xphiles2345]

ill be doing it with openhab as ive had a self contained openhab smarthome for many years now.....but yeah, my thoughts exactly.

[@michaellee6868]

Very cool! I had no idea that cheap WiFi gadgets like this were available, It might help later (at 11:21) to keep the 100 etc. numbers when you rename sensors, eg "101 Return Air Temperature."

[@pablopenasco4254]

Awesome. I want to do this on my own furnace.

[@howardiko7156]

I live in the south and had idea for a T stat that would automatically change from heat to cool and back from cool to heat as required 24 hours a day. Started to look into Ardueno.

[@hjc4604]

I'm pretty sure they already have thermostats that do that.

[@samishiikihaku]

I didn't know I needed this until now! lol

[@jsd21hb]

i just made a similar but not remote, away from home, sort of thing my self with 2 dht22s and an esp32 to monitor how my ac is running when changing fan speed settings. I like to see humidity as well as temp to determine optimal fan speed settings for de-humidification

[@timdestasiohvac]

I have a better setup permanently in my unit that includes humidity. That’s another video.

[@hjc4604]

@@timdestasiohvac Looking forward to it!

[@jmr]

I don't know why I need some of these sensors but I sort of want them now. I might do it with an ESP32.

[@lazman111]

Very cool, can you make this into a recorder to track information overtime?

[@timdestasiohvac]

@@lazman111 I want to and you can export it to excel

[@lazman111]

@@timdestasiohvac Thanks, i’ve been doing service for 40 years and over the time there hasn’t been the greatest devices out there, your simple project looks like to be an easy solution. Maybe you can do a video on the actual download when you get that far.

[@JRBrown-oc2kw]

Wonderful content. As suggested by others, please provide the exact model numbers and your source for them. I like to buy exactly what the expert did.

[@timdestasiohvac]

@@JRBrown-oc2kw i literally put screenshots in the video

[@JRBrown-oc2kw]

@@timdestasiohvac Yes you did. Really did not click in my noggin until I went back for a second look. THANKS!

[@Overdoer949]

Very good content. My issue is with the manufacturer of Shelly, FORCING users to register their personal information just to use the app to begin monitoring. SUPER LAME. @Tim is there another product you have tested or at least aware of that doesn’t require registration?

[@timdestasiohvac]

No I haven't. By the way KZbin/ Google made you do the same thing to watch this video.

[@joeywarcher]

You don’t need their app to use the products. They are local control via the devices webui. I have 38 Shellies and none are in the app

[@timdestasiohvac]

@@joeywarcher the app is much easier to see them all in one place.

[@parkermatthews4368]

Tim, Does this work remotely? Ex. Install at customers house, go back to office and monitor the Shelly app?

[@timdestasiohvac]

@@parkermatthews4368 yes absolutely

[@Electronzap]

Cool project.

[@mxcollin95]

Very cool man. 👍 Love to see people engineering stuff that’s out side the box so to speak with simple components. Are the Shelly app and components meant for HVAC? I’ve never heard of that brand but I’m very familiar with Arduino and raspberry pi.

[@timdestasiohvac]

@@mxcollin95 Shelly is more for home automation. But their devices seem to check all the boxes that I need for my projects. The next thing is learning how to code so that I can develop some software to do some more with it.

[@neilbrookins8428]

@@timdestasiohvacrather than learning to code in the Shelly scripting language it might be easier to connect to home assistant and leverage the entire ha ecosystem for interaction with everything else.

[@timdestasio3367]

I have considered that but I am looking past the homeowner part of it and looking at a contractor solution. I don't think home assistant is a good platform for contractors to use for their customers. What are your thoughts ​@@neilbrookins8428

[@jamesbizs]

“And that’s it”. Lol you make it sound so easy….

[@thisisyourcaptainspeaking2259]

I built mine using an esp32. I like this one, only issue is performing operations with the data and no humidity monitoring.

[@Dennis-ys8ho]

Very interesting video. Do you know of a product - or - can you figure a way to tell me, via WiFi, when my OUTDOOR sump pump is running?

[@stevebabiak6997]

You could use a current transformer or current sensor to detect when current is flowing in the power lines to the pump.

[@aaronpantoja2251]

Anyway to get this to alert you when temps drop or rise to a set temp? Been looking into walk in refrigeration monitoring.

[@timdestasiohvac]

@@aaronpantoja2251 yes i believe so

[@seanmcne]

What are you using to collect, analyze, and act on the data? Home assistant or is there some basic data platform that Shelly provides?

[@timdestasio3367]

I havent gotten that far yet

[@timdestasio3367]

I haven't gotten that far yet

[@seanmcne]

@@timdestasio3367 😂

[@familiefossa2622]

FYI: Shelly provides historical data charts in the app. Have a similar setup to monitor my in floor heating flow and return temp.

[@tscibilia]

I'm wondering if you could elaborate on where you're supplying power to the Shelly monitor. You mention the terminal block and something about after the float switch, but I wasn't sure if you just wire it to the terminals or need to splice the wire into an existing line?

[@timdestasiohvac]

Each system will be different, but you want to grab 24V from "R" and "C". But I like to get the 24V "R" after the float switch instead of before. That way when the float switch trips, it will show up as intermittent power/ communication loss.

[@love2hvac]

Saving this!

[@timdestasiohvac]

@@love2hvac thanks Ty!

[@d5oper]

I assume the sensors are waterproof as this would be a great hot tub freeze warning system

[@timdestasiohvac]

Yes I believe so.

[@Andersonairchris]

Do you know of a humidity sensor we could use with this? I want to log temp and humidity in my crawlspace to fine tune my dehumidifier programming.

[@timdestasiohvac]

@@Andersonairchris I have a video coming out about just that very soon. You can use a plus one with an add-on with one dht22 sensor.

[@avflyguy]

Another gadget I'd like to build, then find 6 mos later I never use it for anything.

[@mattst88]

Never heard this mispronunciation of "peripheral" before.

[@mattst88]

@@timdestasiohvac No, it's a good video. Thanks for putting it together!

[@mattst88]

@@timdestasiohvac (And sorry for not leading with that!)

[@timdestasiohvac]

@@mattst88 sorry for misunderstanding your intentions. I deleted my reply.

[@NutkeyDoesMinecraft]

Very cool!

[@Michael-OBrien]

Does the app support at least a 2-point calibration of the sensors?

[@timdestasiohvac]

@@Michael-OBrien you can calibrate/ offset them

[@robertlitman2661]

These are not thermistor or thermocouple sensors. They’re digital Dallas One-Wire-Bus sensors. They’re factory calibrated internally.

[@Michael-OBrien]

@@robertlitman2661, I expect an NTC element of some sort, but since they have 1/10th of a degree resolution, I would hope there is some adjustment that could be done in the app.

[@timdestasiohvac]

@@Michael-OBrien there is an offset like I said

[@dus10dnd]

The communications wire is 24VAC. Should just use that.

[@EbrahimHasan]

Real genius

[@JRODW]

Is there a transducer add on module?

[@timdestasiohvac]

@@JRODW the add on support analog and digital inputs

[@realSamAndrew]

45⁰ supply air sounds really cold. Especially with the vapor line at 47⁰. Am I wrong?

[@timdestasiohvac]

@@realSamAndrew no you are not wrong. The Bosch algorithm for some reason had my system ramped up for a few minutes and it was making really cold air. The longer it runs the lower it seems to run cold temperature. It typically runs between 50 and 55 °

[@realSamAndrew]

@@timdestasiohvac thanks. Also I found it weird that the air passing the coil was actually colder than the coil itself. Is that even possible? Must be one or the other sensor was a little off. What do you think?

[@timdestasiohvac]

@@realSamAndrew the vapor sensor is not in the coil it’s in the suction line so it’s reading coil temp plus some superheat.

[@hjc4604]

Typically you look for about a 20 Deg F difference between the return air and the supply air. But it depends on the return humidity levels too.

[@timdestasiohvac]

@@hjc4604 yes. At that particular time my unit was backing off a reverse cycle y2 to y1 and Bosch has a delay on the compressor ramping down. The result is an ice cold coil.

[@jamesbizs]

Oh 😅 this is for HVAC techs. Ok. Makes more sense

[@turboflush]

All the stuff a thermostat should be capable of. Why in 2024 can we geek peoples not open a thermostat app and be able to prediag a system or log statistical data?

[@timdestasiohvac]

@@turboflush ecobee gets you close especially with beestat.io

[@turboflush]

@timdestasiohvac I will look. Thanks. Is there a pro or commercial thermostat to look at?

[@darylfortney8081]

You lost me on having to build this myself… should just offer them for sale

[@timdestasiohvac]

I kinda am hinting at that. If you want one built, I'd need to add around $100 to make it worth my energy. LMK.

[@darylfortney8081]

@@timdestasiohvac I’m interested… do you have a website to order from?

[@timdestasiohvac]

@@darylfortney8081 send me an email [e-mail]

[@DustyLambert]

*An HVAC

[@coldfinger459sub0]

I like this 👍