Another day in HVACland. Working on a 200 ton AHU, (2)100 ton condensers and a 68 ton AHU.

[@DelticEngine]

Thanks for an amazing video, Jason! This was a very interesting tour of larger equipment. I imagine there is a lot more risk involved and things to watch for when working with these larger units, that they can bite you a lot harder if great care is not taken. You make it look simple and the way you do things and point out details shows me I'm watching a true professional. I found the blower in the 68 ton unit rather interesting, not only in that it was quite apparent that a lot more attention had been paid to airflow dynamics but that the blower was configured with backward-bladed wheels rather than the more common forward-bladed type. When I looked into this I found that backward-bladed blowers had a much broader performance curve in that they are efficient over a much broader range of operating speeds. This makes me wonder why such a configuration is not the standard configuration given that even the most basic systems, even over the past couple of decades, run the blower at different speeds for different functions.

[@jasonjohnsonHVAC]

@DelticEngine very professionally worded comment. The risk is a lot higher. The potential for something to go wrong is definitely increased. The equipment and repairs are high dollar and much less tolerant to a misdiagnosis by the customer. As for the smaller air handler. Yes backwards inclined fans are more efficient, quieter and do have a larger operating range. It still uses a conventional style housing. It isn't uncommon to see them nowadays as whats called a plenum fan, where it uses the enclosure as a plenum to pressurize it and deliver air through the standard pressure differential process that has been in use for ages. That's all static is. Fluid dynamics is a wonderful subject to understand ( not that I'm some expert at it ) air is just another fluid to move, just like water and refrigerant is. I appreciate your time in writing out your comment

[@ZRock7771]

Keep them coming, enjoy the view and the equipment.

[@jasonjohnsonHVAC]

@@ZRock7771 🫡

[@nholth]

Very cool, enjoyed seeing inside the big air handlers!

[@jasonjohnsonHVAC]

@@nholth appreciate the comment. Thank you

[@haldermand]

We’ve got a couple of RCS140’s tied into air rotation units in a factory we take care of. They’ve been phenomenal.

[@jasonjohnsonHVAC]

@@haldermand those are some big condensers. I'm assuming it's still 6 compressors, just larger ones?

[@jaymartin5095]

Big stuff. Looks like some compressor swaps are in your future. Thanks for sharing this.

[@haldermand]

@@jasonjohnsonHVAC Yup, 6 big Copeland scrolls

[@jasonjohnsonHVAC]

@jaymartin5095 if they approve it. For the customer...having a tandem or trio setup gets expensive. Most manufacturers state that best practice is to replace all compressors in a common circuit. I've had it go bad before. I replaced just one, a month later the other one took a dump, along with the new one. I also didn't do what I normally do nowadays......cut them open and truly find out what killed the compressor...because we know....they don't die....they are murdered.

[@randallweaver7034]

Awesome video! 14:40 filters in backwards

[@jasonjohnsonHVAC]

@@randallweaver7034 it was, wasn't it. Nice catch

[@fshn76]

Great video JJ. Massive isn’t the word.

[@jasonjohnsonHVAC]

@fshn76 thanks for watching brother. Appreciate you

[@eastcoast186]

Thanks for the tour

[@jasonjohnsonHVAC]

@eastcoast186 thanks for watching and for the comment 🫡

[@subcoolHVAC]

You’re on the wrong roof, there’s a water spigot available 😅.

[@jasonjohnsonHVAC]

@subcoolHVAC lol...seriously I was like oh damn...I don't have to run hundreds of feet of hose.

[@subcoolHVAC]

@@jasonjohnsonHVACCONGRATS on 1k SUBSCRIBERS !!!!! 👍👍

[@jasonjohnsonHVAC]

@@subcoolHVAC thanks bro

[@lesstech74]

Had one filter wrong direction. Liking daikin more and more. Very few im my area.

[@jasonjohnsonHVAC]

@lesstech74 didn't notice the filter...good catch. I work for Daikin Applied so that is what I obviously see majority of the time. Thanks for the comment

[@Studentofhvac]

Awesome Bro

[@jasonjohnsonHVAC]

@@Studentofhvac 🫡🤜🤛

[@kindnuguz]

So my hunch is right as I assumed bigger AC's in hotter climate use cascade systems? Because my home AC in northern Utah is single stage 3 Ton and it was almost not able to handle around 104f (or roughly 40c), its R410a from 2013. My mom asked me "how do they handle the heat in Arizona or hotter places?" and I explained to her about a cascade system. Which in lameman's terms is a AC that cools the gas from another and it can stack but they normally have to be different gases. Does a cascade system cool the gas or liquid of the other? I was going to go into HAVC but ended up in IT I love seeing these huge HAVC systems and its amazing what us humans have been able to achieve

[@jasonjohnsonHVAC]

@kindnuguz cascade systems are used in refrigeration, not normally in comfort cooling, but yes you use 2 different refrigerants to aid in heat transfer....that is all we do....transfer heat around to achieve a goal of heating or cooling.

[@kcomfortsystemshvac7060]

Jason,,,,good ,,,tours-…..those compressor they running whit out oil ????can you check the sight glasses 😅😅

[@jasonjohnsonHVAC]

The oil sight glass was empty. I mentioned it to the customer and they are gonna let them run. I did my part in mentioning it. Its on them now

[@linuxman0]

5:00 The label shows 22,000A😳😳 @ 480V!! That's 1,056,000W for just one system. Twice that for both of those big 9 fanners. For the smaller RTU, it won't be too much less. That is a LOT of energy!

[@jasonjohnsonHVAC]

@@linuxman0 that's a short circuit current rating.

[@fathmasameer7523]

What you do if someone locked the door when you enter to that Dino stomach 😅

[@jasonjohnsonHVAC]

@fathmasameer7523 you can open it from the inside as well. It would be a challenge if you were in the blower compartment, they are plenum fans...the whole blower compartment is pressurized....and force is pushing out. It has (6) 15hp fans

[@rickchapman9232]

A few years ago I was working for a hvac company and a guy told us that he was working for one and he was told to crawl through the ductwork and look for tools and trash and he said he got lost then he found a space and stood up got his flashlight and found out he was in the unit. How big would that unit be?

[@jasonjohnsonHVAC]

@@rickchapman9232 that would be a pretty big unit. I've been in air handlers that you need to bring a ladder in to get to the top of the unit. Had one that we used a 12' ladder to get the filters in the top. It was at least 15' tall and probably was around 17'-18' realistically.

[@Eddy63]

Good vid JJ ... Thx

[@jasonjohnsonHVAC]

@@Eddy63 thanks brudda

[@dumptrks]

Yahoo J

[@jasonjohnsonHVAC]

Big Scot...what up brother

[@kindnuguz]

SO my neighbor just got a new compressor and its loud like at the end, I was thinking "not enough oil?" or are certain compressors just loud? They had someone come and replace it and its way louder than mine from 2013. Mine is only loud at the start then its pretty silent and it hasn't been checked since 2014, the guy that did it told me "if its done right you shouldn't need to have the gas/oil checked"

[@jasonjohnsonHVAC]

@kindnuguz unfortunately in residential equipment, checking the oil level isn't feasible. I wish it was, but it isn't. Oil return is a major factor in the health of a compressor. Sound is also tool to use in aiding of a diagnosis. These were low on oil, low on refrigerant and generally not well maintained before we took over. The facility is not gonna be happy with my report. Since these are tandem style compressors.....when one goes....they all have to go...or you'll be back shortly with another failed compressor or multiple compressors. Lack.of oil return can be due to multiple issues....but the core issues is with refrigerant velocity. Without the proper velocity...oil will not be returned and you seize a compressor. Flooding and flooded starts are another culprit. Crank case heaters can help with flooded starts. A functional metering device can help with flooding