RTAC

[chillerguru]

Has anybody encountered leaks on suction butterfly valves.

[acjourneyman]

I haven't but I brought it up at RTAC school as I thought it maybe a potential leak spot, they said it was not a problem spot.

[chillrdude]

So far the RTACs have been pretty good about not leaking, I had one that had a bad weld at the suction flange on the compressor, other than that none that I can think of.

[lord of the screws]

have started 10 rtac with no leaks at suction butterfly valve however there have been 3 from our office that did have leaks there seems to be very random.

[r404a]

Recently found a RTAC185, 2004 date code with a blowing leak on the suction butterfly valve o-ring and through the shaft.


r404a

[nun]

Does leaking by count?

[cw0682]

I haven't had problems with the butterfly valves yet either, Just found one today and RTAC 300 with an 04 date code, blew 415 pds of 134a after developing a leak at the tube sheet of the condensor. I have also seen minor leaks on the shut off valve on the oil return lines.

[CENAIR]

cw0682

I have a RTAC225 that to just lost about 413lbs on circuit-A, leak tested it with 30# of 134-A and brought pressure to 70 psig with nitrogen, went through system 5 times with electronic leak detector and found nothing and usually I can find leaks no other techs can.

Just wondering the leak you had on the tubesheet if was on the header on the power controls sided which is tough to get at or the middle of the chillers tubesheet that you can access?

Any other techs with suggestions would be great, as I was stumped, unit is on roof building has securitey so it was stolen, I am going back Monday with more nitrogen and increasing the test pressure to the max for low and high side and checking again, the butterfly valves were ok too and no sign of oil etc.

Paul R.

[always looking]

We find leaks there all the time. Look for the slight oil trace. What you think is a small leak is usually larger. Had one that I could barely pick up, ordered a new valve when I got back to change it circuit was flat. I think cold climate may affect them.

[CENAIR]

always looking

No trace of oil anywere, not even a small leak trace. What vlave are you refering too?

[BKLYNBORN]

When your leak checking the butterfly vavle open and close it while you have the leak dector thier also we have had problems with the angle vavle on the bottom of the evap not sitting close due to trash in the barrel

[ChillerWisperer]

I've never found a leak at the valve, just leaking by. So there might be something to the cold weather factor, as all the machines I've worked on have never seen freezing temps. The weirdest leak I've ever found on an RTAC was on a load solenoid stem where the coil shorted and burned a small hole in it.

[CENAIR]

I have had a few that had hairline cracks in the stem for the solenoid like the one shown on other units, but none on the RTAC.

R-134A is a little tougher than other refrigerants to find leaks on with electronic leak detectors, thinking of adding some R-22 to the circuit, and then increasing with nitrogen to the max design pressure and re-testing for the leak.

Paul R.

[kwhit]

I have found leaks on two different occasions on the suction butterfly valve seats. You have to order the whole valve because the gasket is incorporated into the valve plate

[always looking]

The leaks we find are right at the stem of the butterfly valve were the handle goes on. No need to remove any insulation usually to find it but you have to have a good leak detector. The usually leak over the winter. We're in a cold climate.

[mustardman]

I have only had one personally heard of a handful of others.

[kwhit]

never had a leak their before. I believe the valve is made by a company called Sure Torque? I would look into any recalls on their valves

[Manu1]

We have seen some issues with those valves, the important part is that if you need to replace it make sure to torque it in star pattern @ 60ft/lb. I would recommend to start @ 30 then increase to 45 and finally 60ft/lb. just to prevent damages to the seal.