Refrigeration

[BonesD]

Howdy,
My 43 year old boat has a 43 year old refrigeration system.
Old York compressor and sea water cooled system. That I don’t really understand.
Anyway the belt was pretty loose when I bought the boat and the compressor was out of alignment at the time.
Tightend the belt and topped of the refrigerant as there were bubbles in the dryer sight glass.
Fridge chilled down great for two days or so.
Then the compressor started locking up so figured I over charged it or there was air in the system.
So I aligned the compressor best I could and it’s not far off now. Still not perfect. Cranked it up and started the compressor, still locking up so I bled a bit of gas off a bit at a time until the compressor runs properly. Sight glass is still free of bubbles so it either full or completely empty!
But the fridge doesn’t cool anymore.
I found the installation instruction but no mention of manufacturer or just plain operation in 30 plus pages.
I don’t know if I am neglecting to turn something on or not. The only control is a breaker marked compressor circulation pump.
When turned on the compressor clutch energizes and the sea water pump comes on and circulates water.
Am I missing something?
I am set to put a vacuum on the system and recharge just to be sure it’s gassed up but hate to if not needed.
Any suggestions besides replacement are welcome.
Thanks
Also or and, the instructions say something about a coolant tank that takes X amount of water and antifreeze.
I have not spotted that yet.
Thanks

 

[Ste. Claire]

Hello.
When u added refrigerant did you have a refrigeration manifold gauge to access the system and if so were you able to access both sides of the system?
Typically if you have a site glass the equipment usually has a receiver to essentially store more refrigerant when the equipment is under a load. It’s not likely u overcharged it though using a scale does help with charging the system.
Would be interested in seeing a couple fotos.
JB

 

[DavidM]

Is the compressor driven by DC or AC? I presume not engine driven because you talked about a breaker.

It usually works fine to charge until you see the bubbles just disappear so it is doubtful that you over charged it by much. When you bled it you probably dumped all of the refrigerant and the sight glass is showing just gas.

So evacuate the system as planned, start it and slowly add freon (you do have the right type, right?) and watch the sight glass as bubbles show up and slowly clear, then stop charging immediately.

It wasn't clear if the compressor was starting ok. If not and it is AC powered then it is often a bad starting capacitor.

David

 

[BonesD]

Thanks for the reply. I do have a manifold but didn’t use it the first time around.
I hooked it up earlier and the discharge side was only showing about 120 pounds.
Suction wasn’t registering but I may not of had the valve open when I checked it. Goofy gauges. There is no cross over valve on the manifold, just an in line valve on the suction line and another on the discharge line. I just gave away a good set 6 months ago when I decided to live the boating life. Didn’t think I would need them. Duh. I will send you some pictures later. On my way to town to pick up a evacuation pump at the hardware store. I opened up the suction line and got no pressure out of it(engine off) and then bled the discharge which only blew some moderately cool air/refrigerant but not a lot of pressure.
I’m guessing it has a leak somewhere. I will run the pump for a few hours and then see if it holds a vacuum over night. If I can trust the gauges! It looks
As though the system shares the condenser and maybe the evaporator for the Aqua Air system.

 

[BonesD]

The compressor is engine driven. The breaker is on the D/C panel. As far as I can otell that is the only switch to energize the clutch. It also starts the raw water cooling pump. If it does anything else I am not aware of it. . The System needs to be run 30 minutes or so a day to keep the cooling plates cold. It was dropping down to 17 degrees F when it was working before. There is an adjustable thermostat simewhere. Maybe I need to look in the food box itself.

 

[BonesD]

Pictures
In reverse order
1st dryer(accumulater).
2nd sea water circulating pump. Pay no attention to wires on flooring. Extra bilge pump.
3rd condenser also used on Aqua Air ar least the plumbing indicates it.
4th Aqua Air heat and a/c unit behind the silver insulation
5th sea water circulating pump for Aqua Air. The same sea cock feeds both pumps but they run independently of each other.
6th. d/c breaker panel. Breaker at bottom supplies power to the compressor clutch and the circulation pump.
Now the interesting part
Inside the cold box are refrigerant lines going to these silver covers. Don’t know what s inside. Perhaps the cold plates.
The top of one has a valve like you might find at the bottom of a radiator.
And finally just an overhead view of the cold box.

The cheapo gauges I found on the boat.
The suction side gauge rotates to open or close. My mistake. The high side does not.
The suction gauge bottoms at zero so applying a vacuum does not show diddly on the gauge. I have the pump running and will shut down after an hour or so and disconnect. I will open the suction line in the morning to see if it any atmosphere rushes in. Hopefully it will, indicating it held a vacuum at least overnight.

 

[Ste. Claire]

If u can get a hold of some gauges and some nitrogen I would put a test hold of 100psi on both sides. Usually what I do with my customers is put a dye kit in and let it run a couple days then return with a UV light and look for the leak. Since you are where you are now, get a “holding charge” in it and get an empty squirt bottle and fill 20% Dawn liquid dish soap and the balance with water.
Spray all the fittings going to and from the unit then look for bubbles.
If you cannot get nitrogen look at the data plate on the top of the compressor and run the numbers u can use the refrigerant as a holding charge. If the equipment is original and hasn’t been switched out the oil in the compressor will be “MIN” for mineral or “ABO” for alkyl benzene. Pending on the compressor data then it can be determined which refrigerant is required for it. If I had to guess with original equipment it’s R12 or R22.
Finding the leak is half the battle.
Let me know what you discover