McQuay Leakers

[HVAC_HD]

I noticed in one building I work in we are having a large number of refrigerant leaks on McQuay 410A water source HP's. Install is around a year old performed by another contractor. I've found numerous units where I put my gauges on and there is no refrigerant in the unit. Any info on possible bad production run or something I'm missing?

[madhat]

Of all the WSHP, McQuays leak the least, R22 or R410, did the contractor tap an accessory into the WSHP, such as a Water Reg. Valve, leave the schrader caps off, or loose the little "O" rings ? We had a batch of console R22 units 17years ago, that the high pressure cut out, vibration leaked, snapped off and it only happened on the right hand units.

Little recent story on a small core WSHP, other HVAC guy was doing a start-up on a new unit. Next day he was cussing and fuming, piece of 'junk' is going to have to go back to the factory. Asked, "what was wrong" He said "it just starts heating, then switches to cooling and shuts off, the only way to restart is to turn the breaker off." Yes, both water valves were closed, the unit goes back into cooling to warm the water coil up just before locking out on High Pressure.

[airmanone]

I've never had too much trouble with McQuays, at least not any more trouble than other brands. I think you can always get a bad batch of units from the factory...any factory.

[HVAC_HD]

Of all the WSHP, McQuays leak the least, R22 or R410, did the contractor tap an accessory into the WSHP, such as a Water Reg. Valve, leave the schrader caps off, or loose the little "O" rings ? We had a batch of console R22 units 17years ago, that the high pressure cut out, vibration leaked, snapped off and it only happened on the right hand units.

Little recent story on a small core WSHP, other HVAC guy was doing a start-up on a new unit. Next day he was cussing and fuming, piece of 'junk' is going to have to go back to the factory. Asked, "what was wrong" He said "it just starts heating, then switches to cooling and shuts off, the only way to restart is to turn the breaker off." Yes, both water valves were closed, the unit goes back into cooling to warm the water coil up just before locking out on High Pressure.

I actually found that the leaks were mostly coming from the schraders. McQuay used a fitting that is not a standard schrader. Same function just a little different design. Only flaw is that they seem to have a tendency to work themselves loose on some units. Used some Nylog on the threads during repairs. Seems to help out a little. May want to check them in the future on PM's or service just to be cautious.
I love those calls! Especially when people diagnose a blocked strainer as a "non functioning" TXV/ liquid line obstruction, because it's cutting out on high pressure. HAHAHA!

[C-Jac486]

Putting in new McQuay WSHP 410-A now... having problems with the fan wheel falling out of the cheap plastic bearing.... McQuay service came out and agreed with us that the fan wheel shaft is too short or pressed into the hub too far. He would advise the factory to make changes..... so far no leaks but they have only been running about a month!

[chiller mekanik]

We've had two R-410A units leak on the evaporator & they are about 18 months old.

[C-Jac486]

It's been two months installed 45 units, four, flat out of gas