Check valve going off

[Kollason]

Hello lads,

I have a chilled water system with Copeland scroll compressors. After replacing a compressor and refilling it the compressor started up nicely. After running for a while normally i got a bit concerned with a lot of condensation on the outside of the compressor compared with the other ones. After about 5 minutes of running it started opening the built in check valve and starts releasing first about every 10 seconds then gets more frequent down to about 3 seconds. This happens with the operating pressures at normal levels.

Advice would be very much appreciated.

[chemi-cool]

Define "operating pressures at normal levels".

Have you checked the currant drawing?

[Grizzly]

Did you Vacuum the system first and weigh the charge in?
Grizzly

[nike123]

It look like liquid floodback.
What is suction superheat?
Describe how did you determined refrigerant charge.

[Kollason]

Hello boys thanks for a quick reply,

I did not vacuum the system before installing the compressor no. Just closed the inlet and the outlet valves of compressor.

Logged operating pressures for this system have been 18 bar HP and 3.2 bar suction.

When re filling kept filling until sight glass was full. I have no real indication on how much is actually in the system as i unfortunately do not have a vacuum pump or a scale on board.

I checked the suction superheat and it is about 13°C colder than the other compressors or about -2°C.
What could possibly cause this?

[nike123]

Hello boys thanks for a quick reply,

I did not vacuum the system before installing the compressor no. Just closed the inlet and the outlet valves of compressor.

Logged operating pressures for this system have been 18 bar HP and 3.2 bar suction.

When re filling kept filling until sight glass was full. I have no real indication on how much is actually in the system as i unfortunately do not have a vacuum pump or a scale on board.

I checked the suction superheat and it is about 13°C colder than the other compressors or about -2°C.
What could possibly cause this?

Overcharge!

Recover refrigerant until you got 8,5°C subcooling and than check superheat at evaporator outlet.

Did you said that you did not vacuumed compressor (and system) at all before recharging it?

[desA]

Ouch!!!

[Grizzly]

I would stick to the marine engineering
Kollason!
Because you are not doing anyone any favours ignoring the basics!
Grizzly

[lawrence1]

Probably hasn't got a vac pump.

[Deniver45]

I will give you this! YOU CERTAINLY ARE AN HONEST GUY, and that for sure has it's plusse's. definitelly OVERCHARGED, ( and NON-CONDENSABLES)

I knew it when you said "lot of condensation on the outside'.......... I think you may have liquid in the suction line going back into the compressor. = no superheat since your gauge temp and line temp will almost be identical in a situation like this.

It is not uncomon to have ice on a suction line in commercial refrigeration. BUT, HOW COULD YOU NOT PULL A VACUUM? Did you change the dryer?

MAN! it is SO EASY to do this right; in fact it is AS EASY to do it right, and you did this all wrong.

I would OPEN the system back up before the moisture ( non-condensables) eat away at your new scroll and PUT A NEW DRYER INTO THE SYSTEM AS WELL. Pull 500 microns on a vacuum gauge; any lower and you could boil out some of the oil in the compressors base.

WHO has a document they have new customers sign to agree to pay?

Thanks,

[Deniver45]

Hello boys thanks for a quick reply,

I did not vacuum the system before installing the compressor no. Just closed the inlet and the outlet valves of compressor.

Logged operating pressures for this system have been 18 bar HP and 3.2 bar suction.

When re filling kept filling until sight glass was full. I have no real indication on how much is actually in the system as i unfortunately do not have a vacuum pump or a scale on board.

I checked the suction superheat and it is about 13°C colder than the other compressors or about -2°C.
What could possibly cause this?

I just bought a new 9.8 CFM vacuum pump from "Fiery Chill" and they have them on close out. I paid UNDER $300 for an AIRSECO = Thermal vacuum pump because it cost's $250 for a rebuild kit for my 1983 1.6cfm pump from thermal. You can get a 1.8 cfm Thermal pump for only $119 here = http://fierychill.com/closeouts/vacuum-pumps

Write Bobby = FieryChill Customer Service <info@fierychill.com> ( Bobby Bonitati - FieryChill Customer Service - 1-800-575-4180 ) there and tell him Daniel from Twin Rivers Restaurant Svs sent you over and he could PROBABLY knock that $119 down to $89 IF YOU PAY THE UPS CHARGES!

YOU WILL NOT GET A BETTER DEAL!

Good luck,

[Deniver45]

the valve is being FORCED open due to overcharge. Go get that NEW VAC pump I wrote you about for $119 NIB from Bobby @ Fiery Chill.

[Deniver45]

anything else Kollason?

[Kollason]

Thanks boys, and thanks for the sarcasm as well seems i offended a lot of people.... What confuses me though is that the sight glass now is not full and the pressure is about 1 bar under normal operation on the high pressure side and about half a bar on the low. Will need to get a vacuum pump though.

[james10]

sounds like it's got a leak on it or the ambients have dropped a bit whats the weather like in bermuda i need a holiday