Lennox RTU's AHHHH!!

[ZeroTolerance]

I have 5 Lennox LGA120H RTU's. The GM is complaining to me that NONE of them are cooling off his building and I checked SH and SC and pressures and they are all dead on. IDK wtf he is expecting but apparently he lives in a perfect world or I am missing something. The temps of the units are 82, 81, 77, 85, and 83 and are all set at around 72-74degree F on the therms. I told him its gotta be an insulation problem but he INSISTS that they units worked perfectly last year at this time.

IDK, but the only think I can think of that is off is the economizer board, because the dampers were set to open at 100% manually and for some reason are not automated like they should be. Any suggestions. I am at a loss and don't know what is going on other than his building is poorly insulated. I have since set the dampers to 10-15% OPEN and still have the same issue with temps.

All pressures at 95degree F ambient are 75psig suction (tolerance +-5PSIG) and around 270 discharge (+-10PSIG).

Blower is running at 9.0A and blades and belts are in good shape. Evap out temp is 49degree F.

When temp is cooler outside the inside temp is close to right on, then he complains that when the outside ambient temp rises (95degree) so do the inside temps. This is going to occur because as temp rises so does pressure

Leaks in his returns or supply vents possibly do to varmits? IDK havent checked that yet

I closed the dampers to 0degree and all the A B C D DIF potentiometers are set to DIF and DIP switches are all set to Global

Frustrating as hell, I've had two different HACK companies come out and one keep BS'ing me of when he was going to be there.

The first company that I had come out didn't even bring his gauges to the roof and all he checked was the temps of the suction and discharge by FEELING THEM WITH HIS HANDS. WTF? He also checked amps of the condenser fans and blowers. Then all he did was adjust the dampers. HACK

The second guy told me he would be there at 1pm cst and so I called him at 1:30 and he said he was stuck in traffic but on the way and said he would be there in an hour to hour and a half. Well two hours passed and I called him and he said he was in some city and said he was on his way and would be there in 30min. So an hour passed and I called him and he said he was in richardson and on the way be there in 30min. At this time it was around 4:30PM. So I asked him wtf happened to 1pm? He said a call took him longer than expected so I said well why didn't you call me to give me an update that you were going to be late? He told me he hasnt called anyone and I laughed and said, "so this is how you run your business? Rather unprofessional if you ask me especially if I have to call you to see where you are at." So I told him to forget about it and wished him best of luck with his hack business.

So at this point the GM is on my ass seeing as I am the facilities manager of the restaurants. So I told him I was sorry and take full responsibility for the situation and not having the units running properly. So I told him just go ahead and call who you prefer.

So his preferable company came out and said the condensers were clogged WHICH I just cleaned them with nu-brite and a pressure washer a week earlier (as stated before) and all the pressures of the system were within tolerance. So they are coming back out this morning to clean them again. Which I don't think is the issue but we shall see.

I would prefer to use TD Industries and have toured their facilities and taken classes with some of their management personnel. I know they are a reputable company but when I have A/C problems that I can't resolve myself I need someone to come out ASAP and they can't but it seems all the "Hacks" can because they are hacks. AHHHHHHHHHHHHHHH

The kitchen RTU has non-condensables in it as the high side gauge keeps fluttering. So I need to recover, purge with nitrogen, install new drier filter, purge with nitrogen again, pull a vac, then recharge by weight.

Joe Harper - Check my sheaves to see if they are polished? The kitchen units belt was smooth as a babies butt causing it to squeak like a SOB. I since replaced it and its running at 9.0Amps. Neglected to check the sheaves though

[ZeroTolerance]

Guess everyone's stumped just like me.

[multisync]

Do a full heat load calc..

[ZeroTolerance]

Will do, but my problem is that everything on the building has been working fine for the past 10years, and now all of a sudden the building is not cooling?

[Brian_UK]

Can he prove that it has been working fine for ten years or is it heresay?

[ZeroTolerance]

That's a very good question ROFL. I honestly don't know how long he has been there but he has been there longer than me and I have been there a little over a year.