Measuring Airflow CFM on HVAC Systems! Finding Airflow Problems!

[@edisonhvac]

Great video on measuring airflow in HVAC systems! This ties in perfectly with the newly approved ASHRAE Standard 241, which emphasizes the importance of managing airflow to reduce the risk of disease transmission in indoor spaces. Your practical demonstration of ensuring proper airflow and identifying airflow problems aligns with the standard's requirements for equivalent clean airflow rate and the use of filtration and air cleaning technology. It's exciting to see how HVAC professionals can apply these methods to create healthier indoor environments. Keep up the good work!

[@acservicetechchannel]

Thank you for your positive feedback and insightful connection to ASHRAE Standard 241! I'm thrilled to hear that the video on measuring airflow in HVAC systems resonated with you!!

[@garysmith9772]

Anyone in the HVAC industry whether they realize it or not is selling airflow. In the 35 years that I’ve spent in the HVAC industry, I tried to measure even on a service call the X ternal static pressure of every job. I could probably count on one hand, the number of installations that actually met the manufactures maximum external static pressure of 1/2 inch And we need to make it mandatory that to pass an inspection. The inspector must do an external static pressure test of every install. Just my opinion.

[@ironwill3598]

I agree, but here’s the problem with that. I’m here in Colorado, and many houses, especially older ones were not built with good ductwork. They were WAY too small to allow the proper CFM through at the correct velocities (and/or) static pressure. With lots of my customers it’s: “We either need to gut your house and replace your duct system, or we live with high static pressure”.

[@hightttech]

New home builders are getting away with gross framing, electrical and plumbing errors, and PASSING inspections. HVAC details are SO FAR OFF THE RADAR that homeowners should be grateful if the thing even cools at all 😢. Sad state of affairs.

[@mrtomJ316]

Air balance test is. Even a bigger joke inspector wanted it. Was funeral home he just drill and. Plugs holes and messed with my Honeywell jado controllers on damper $2200 . And a tube of silicone to caulk 50 Plugs may the Good lord keep everyone safe

[@rachelpickert6385]

Loving the content. Informative! 😊

[@joshuahatridge3833]

Thanks Craig! I’ve been looking at the truflo grid and hoping you would do a video.

[@arnelcaburnay4004]

The return is with high static according to the video, but you did mentioned if the total fan static can handle both supply/return and internal static. If it can handle and design for that, so there’s no issue.

[@juanacosta2788]

Hey great video I never nkew that u made it look easy ill definitely get that book

[@centauri8820]

I think my 2.5 ton system has a slightly low charge. I measured a static pressure before the filter and before the evaporator and got 0.43 WC. The med-high fan setting for my handler says 0.4 is 1031 and 0.5 is 987. So pretty much 1000CFM yet it froze up on me one day when it wasn't really hot out but just enough to trip the t-stat. I set my house at 76F so it's definitely not over-demanding. This only happened when I moved it from high to med-high, figured I'd try to make it a little more efficient since the numbers lined up. It did run a couple weeks with no issues but it was warmer in that time.

[@izzymoney85]

Thanks! once again Craig for All you Do very grateful 🙏👍

[@eric01406]

Great video as always! Quick question. How would you use this if you have a variable speed blower motor? Don't they always maintain airflow no matter what restrictions there are unlike PSC and ECM motors?

[@Demoralized88]

If that's how they actually work, they must be monitoring the pressure to maintain a certain flow. The only thing that would matter and be helpful to test would be power consumption for the blower as presumably it would be inefficient with restrictions. I've seen people claim that VFD HVAC equipment does this but have some questions/doubts about the effect and manufacturers actually implementing the components to do it.

[@chesstime356]

As always I really really like your videos yes another nice video….

[@acservicetechchannel]

Glad you like them!

[@zipperdingo6385]

Craig is awesome

[@acservicetechchannel]

Thank you!

[@rozilla_the_savage4445]

Love this channel

[@HVAC_Tips_Tricks_Calcs]

Another great video, thanks. Would love to see an unbiased test of tf grid vs. the manufacturer blower chart vs. hot wire anemometer. $1800 is a lot of dough if the other methods work as well. Plus I’m almost at the point of having to take a tractor trailer to the job site with all the tools I 'must have'-like this and a blower door kit. On side note, does Craig ever sell all these tools he gets to try out? I’m sure a lot of techs wouldn’t mind sone discounted tools (probably a legal/tax issue).

[@mackenziegray2090]

I use the fieldpiece anemometer. $300 or so still kinda pricy but it's allot more affordable and pretty easy to use.

[@HVAC_Tips_Tricks_Calcs]

That’s what has been working for me. That and static pressure.

[@seahog1911]

I feel for you buddy. I’m retired, but I went from 3 refrigerants to 6 and all that. I changed jobs and got into commercial and industrial dehumidification and some VOC removal systems. That was my dream job after 20yrs of HVAC&R service office bldgs and commercial rooftop stuff. Can’t forget the fun Follet ice machines lol. Find your niche and perfect it.

[@garysmith9772]

Craig I’d like you to measure the pressure drop across that media filter it’s got to be .3 or better.

[@andrecampbell9899]

Cool do they have a similar procedure for heatpumps Great Content ❤

[@Demoralized88]

It should be literally identical to the system shown in the video. The only difference for a split Heat Pump is the reversal of coolant flow and the Evap Coil being hot instead of cold like with AC. Nothing changes with the indoor equipment or testing

[@Jason-qe4tp]

Can you do a video on ewc and/or honeywell damper control troubleshooting please

[@toolemanful]

Like to get the gauge is there a link on that

[@clove1696]

How do you use this if there are multiple returns and no media filter? Would you do them individually and add them together?

[@james6794]

00:02:23

[@icefireroo]

Love these videos. How would this work if you had a system with two air filter slots (one on top of the other)? Would you keep one air filter in and use the TrueFlow grid in the other air filter slot?

[@james6794]

00:02:23

[@Alex-jo2oi]

Craig, what might be the best way to obtaining my HVAC/R License in NJ? I’m working for someone who is willing to document my hours with DOL and pay for school. just need to find the best way to do it and think you might be helpful in knowing that. Thanks!!

[@noufalkilayil7713]

airflow airflow airflow 👍

[@Michaelgallant171]

ABC ABC ABC ABC

[@coolramone]

4 point airflow check (if you don’t have a filter 3 point) to determine problem area and shooting for 0.5 inch total static pressure and ~400 cfm/ton.

[@reuebenalvarez5619]

Awesome 👍🏽

[@ronniekeys1946]

What's the next step to finding the problem

[@pizzle1011]

👌🏾👌🏾👌🏾👌🏾

[@entertainmentknowledge264]

Just want to ask about the superheat chart for the piston system, your chart in the book we got don’t show the return temp more than 76f The temp at the return was 84f and the supply was 76f. I don’t know what to do in this case! I need to calculate the target superheat..

[@MsckMatt]

I aim for about 12 degrees-ish for superheat on pistons, while trying to get around low 50s on the suction line temp. At 84 degree return, I would probably aim a little higher on the superheat since theres a big heat load in the house. If you are nice and cool on the suction line temp, and your temp split is good, you should be looking good to go

[@joshuahatridge3833]

Superheat requires certain parameters to work. You need to get close to those parameters before setting the final charge. For instance in this case let the unit run long enough to bring down the return temp and then set the charge. There are plenty of techs out there that set superheat at the same setting regardless of temp/chart, however they are putting components at risk.

[@lengnuan913]

I have a 5 ton AC, always got frozen evaporator, never work properly from first day. The ESP before filter is -0.07 inWC, after evaporator coil is 0.08 inWC, the total 0.15 inWC, what will cause ESP too low. Turn on the heat at highest speed, the gas output is 111,000 btu/h, delta T is 68F, the total CFM is 1500, something wrong with ductwork system. Any opinion and suggestion, much appreciated

[@eric01406]

You'd probably need to get larger ductwork.

[@mikefrom3089]

Sounds like you over sized your system. 400 cfm per ton is rule of thumb.

[@123glegra]

Did I missed something or you had two different results while testing exactly the same equipment.?

[@UncleEarlHeatingAirCondition]

The first measurement was only CFM delivered from the blower out. The second measurement was the CFM delivered when you include your system Total External Static Pressure Measurement, your whole ductwork.

[@alk734]

I have question for any expert, I want replace my 1/10 hp condenser fan with 1/4 hp, with same rpm, is it OK? I will make sure put new capacitor that is rated for 1/4 hp fan Thanks

[@ironwill3598]

Depends on how you look at it. * Condensers have fins & hail guards which produce static pressure. * You need HP to overcome that static pressure. * Motors need to run efficiently. Under amping or over amping is inefficient and results in shortened life expectancy. A motor than is more powerful than needed in a condenser may cause it to run inefficient. (I say “may” because I’ve honestly never tried it, so I don’t know exactly) * By all means, you can replace your motor with a different HP, but it will shorten the life expectancy (sometimes drastically). I will leave the rest up to you.

[@alk734]

@@ironwill3598 thanks

[@mikefrom3089]

It’s fine induction motors don’t need a load

[@Demoralized88]

Induction motor 'power' rating and consumption are dictated by the load. Meaning, speed rating is most important and a higher power rating only matters IF it's having to do a harder job i.e. more 'work'. If both are rated for 3600 RPM, they will operate the same with the only difference being the 1/4HP can handle more resistance and maintain the rated speed over the 1/10th. Again, power is determined for Induction Motors by the load imposed on them and speeds are fixed at the rating unless the load exceeds the power rating. A bigger motor with a higher rating (if it fits, that's the biggest thing with AC motor frame/sizes) won't faster or draw more power for the same load/application, it's just telling you that it can handle more resistance than the 1/10th motor from the OEM.

[@alk734]

@@Demoralized88 thanks

[@mrtomJ316]

Where did you get the cfm reader is that. True. $1800. Thank. You May Jesus Christ Bless you and your family

[@mrashad219]

How much is this tool

[@richwuttunee4734]

Where’s the links for purchase ?

[@acservicetechchannel]

They are in the video description section, thanks!

[@joecooksey4331]

You don't need all that fancy stuff... just get the suction to beer can cold and you're good to go. LOL

[@mikev.1034]

👍🤘🤙

[@woodygotem]

Oc it cost that much 😫

[@abdorakeebnaji1527]

We waiting for the refrigeration system and troubleshooting book...

[@vahyae431]

Speak for yourself pal

[@1LOVEABRAHAM]

not all filter house is made good I have no time to fix people's filter house they don't pay , I ain't going to buy all this big goofy plastic all over, techs ask the homeowner to do airflow they have to pay to fix their filter box , don't say you want to do airflow and them spend hours bending and straighten and correcting their messed up system, 80% of them are messed up anyways, people are cheap these days just fix the major issue and leave. don't get your headache, if it's not broken don't fix it. keep talking too much to the homeowners you might get your self in deep s. if the blower motor is weak just find the issue fix or replace it keep it moving period. I have education in hvacr I worked 19 years as Hvac I know work for government less headache, the private is Hvac job is trashy and I used to go home with headache many of the customers are lairs.