My problem is I have a 3hp semi hermetic compressor that keeps blowing the gasket out between the valve. BTW this is for a walkin freezer . I'll give you some backgroung info on this.
unit started blowing a 15amp 3 pole breaker. custodian at school would reset the breaker and all would be fine for awhile. I finally get the service call to look at the unit. This is in january. The freezer is no longer holding temp. So i see there are bubble in the sight glass at the compressor. I decide to hook gauges up to see what this bugger is doing ,after i took amp reading which are 2 -3 amps higher then should be. Well my high side is at 195 low side is at 50. gauges are very erratic. high super heat at compressor . cant remember exactly but l think it was 80*. well something told me it might be the valves with the erratic gauges so I decide to see if this unit will pump itself down. So i start to front seat the reciever valve slowly to watch to see if it starts pumping down and LS stays at 50.. so i totally shut it and it still stays at 50. I say valves! so I end up evacing down and pull head. valves are trashed and gasket is blown.pistons go up and down still and cylinder walls aren't too bad. What caused it. im figuring flood back when unit kept being reset at breaker. Let us see if I can get by with just a valve plate.
So i clean unit it up with new valve plate. reassemble torqe to spec. evac and recharge. The condensing unit holds 20.6 lbs 502 at 90% so i add 18 lbs 408a to start unit so i can check sight glass. All good. NOT 4 LONG!!
The compressor starts pulling box temp down. pressures are HS 195 LS 25.
-5* SH is still way high but box is 70*...Well runs for about 15 minutes and bang!! pressures go to 200 HS 50-60 LS and compressor is pretty noisy. AHHH! First Thing I think is the valves are wrecked again. so i try pumping down and yes they are bad.. BTW the amps were low the whole time till it broke again. It didnt wipe the valve but blew a chunk out of the gaske between the valves. WHY? I think compressor must just be wore out it is 30 years old and has some damage from last problem , head may have even been warped. So I order new compressor. I'm not gonna deal with this crap.
New compressor installed charged with 408a . Box pulled down. SH 28*at compressor. I think 10* at evap. everyone happy! Also new TEV thought this might be going crazy and flooding compressor.
Friday last week call freezer is tripping breaker. and box is warm. Not again this is 4 months later.. WTF! Sure enough its happening again with the new compressor.
Please shed some light on this if you can. head gaskets are cheap i Have found out.. But the amount of beer this has caused me to drink after hours is getting expensive, and the wife says I'm in a bad mood all the time.
I'll see if i can get a few pics off my phone to show you where its blowing the gasket at.