Refrigerant Low??

May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
How do I know if my refrigerant needs recharging - I've read here that people's refrig cycle on 6-10 minutes per hour. Mine is substantially more than that and I'm wondering if it needs a recharge. I don't know how old but it is probably over 20 years old (no led trouble lights) - alder/barbour and may have even come with the boat (1984 Catalina 36) - so probably the banned Freon ? - can it be charged up? Any recommendations of who in Everett to do the work ??

Thanks
Les
 
Nov 26, 2008
1,966
Endeavour 42 Cruisin
First, try to find make and model number of the compressor and google that for info. Might also be a tag on the unit labeling which referigerant. Since Catalina is still in biz, contact them to see what they can tell you about the unit.
 

sdstef

.
Jan 31, 2013
140
Hunter 28 Branched Oak Lake
It is probably R-12. There should be a tag on the unit which will show charge quantity in ounces. There are other ways to find out taking a pressure reading and then the ambient temperature. A pt chart will show you. Probably better left to a tech. Look for signs of oil around fittings etc. If you find oil, it will be leaking gas too. You can charge with alternative refrigerants like one called hot shot, without changing the oil charge. Again, that may be better left to a tech. Good luck.
 
Oct 30, 2011
542
klidescope 30t norfolk
Call around marine refrigeration company's or just refrigeration co's and ask if they have any r12 in stock that they can recharge an old unit. But what ever you do try to keep that old unit it's so efficient only needs like 4 amps to run a 10,000 btu unit that's half of a 143a unit and a quarter of 410
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
The way you tell if it needs a recharge is does the evaporator get down to the temp on the thermostat or slightly colder. Mine AB runs for 20 minutes then cycles off for 20-30 minutes (50% duty cycle) but I also have a holding plate so the thermostat is designed differently. You should be able to hear the thermostat turn on the compressor. with the door closed hearing it turn the unit off is problematical though. If the unit is turning off due to a superheat of the condenser (safety stop) then coolant is not the problem and you need to look at cleaning the condenser or fan/water flow to it.
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
I talked to the refer guy here. He asked a bunch of questions and basically said it doesn't sound low on coolant. Basically he said if the evaporator ice's up heavy on ones side but not the other it is a Sure sign of low refrigerant. Mine is very uniform. It is just running long periods of time and sucking the battery. He said it was probably a tired compressor. It could be original to the boat (1983). Next time I'm at the boat I'll empty the lazerett and check for tag info.
 
Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
Do you keep it pretty much full so there is not a lot of warmer air to cool down?
 
Jan 17, 2013
439
Catalina 310 St. Simons Island, GA
I am not buying the 6-10 minutes per hour. I have a well insulated fridge because I added additional foam insulation and also have a brand new Adler Barbour compressor, evaporator and lines and it runs pretty frequently, especially in the summer. I would estimate 40% of the time.
 
Sep 25, 2008
1,096
CS 30 Toronto
I have a 2007 fridge, added 1" solid foam insulation with a silver foil inside.
The fridge runs 10-15 minutes per hour in the summer. Contents about 50% full, mostly beer and pop.
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
Thanks. I'll look into adding insulation. Much cheaper than a compressor/evaporator upgrade
 
Feb 8, 2014
1,300
Columbia 36 Muskegon
Is this a new development or had it always been that way (since you've owned it?) Most ice boxes from the eighties were not well insulated, and what was there could have degraded over time. The better insulated, the less the machine will run. Adding more is almost always s good idea.
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
Only owned since April. Started working when on hard and it completely drained the house in 24hrs.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
There has been a recent change in the way reefer compressors are designed to run. For a long time the use of holding plates dictated that the compressor run "as fast as possible" to bring the holding plate down to temp. Somebody noticed that it is actually more efficient to get rid of the holding plate, and run the compressor at a lower speed for a longer time. So we went from run real fast (high amp draw) till the holding plate is down to temp and then slow cycle to keep the holding plate at temp (always running real fast) to run much slower (low amp draw) to keep the evaporator down to temp but do it for longer cycle on times.
Holding plates where desined to have the compressor turned off once it was (once a day while charging the batteries BTW) down to temp and then release the cold for the rest of the 24 hour period. That required that the owner actually monitor things (the horror!!!) and there is basically no appetite for such onerous activities in the current boat owner population.
 
May 23, 2016
217
O'Day 1984 23 Island Park, NY
Use a meter to measure current draw with the compressor running... If it's significantly below the current rating on the tag then its likely low on refrigerant which makes it easier for the compressor to run, making it draw less current
 
Jan 17, 2013
439
Catalina 310 St. Simons Island, GA
This makes sense and matches my experience with a brand new AB compressor & evap in a well insulated compartment.
bob


QUOTE="Bill Roosa, post: 1358077, member: 77182"]There has been a recent change in the way reefer compressors are designed to run. For a long time the use of holding plates dictated that the compressor run "as fast as possible" to bring the holding plate down to temp. Somebody noticed that it is actually more efficient to get rid of the holding plate, and run the compressor at a lower speed for a longer time. So we went from run real fast (high amp draw) till the holding plate is down to temp and then slow cycle to keep the holding plate at temp (always running real fast) to run much slower (low amp draw) to keep the evaporator down to temp but do it for longer cycle on times.
Holding plates where desined to have the compressor turned off once it was (once a day while charging the batteries BTW) down to temp and then release the cold for the rest of the 24 hour period. That required that the owner actually monitor things (the horror!!!) and there is basically no appetite for such onerous activities in the current boat owner population.[/QUOTE]
 

DougM

.
Jul 24, 2005
2,242
Beneteau 323 Manistee, MI
OK, now I am curious.
Like Ron, I have a Beneteau 323. Bought new in 2004 and literally have never used the fridge, primarily because I day sail it, and its docked 50 feet from my house, so the liquid refreshment stays in the house fridge.
I tried running the boat fridge once (empty) and the compressor never shut down. Consequently, I said to heck with it. I figured it was low or out of refrigerant, but there is no Shrader valve in the refrigerant line, so not wanting to cut the line and lose any refrigerant, I didn't attempt to install one.
like most manuals, the one that came with the unit is anything but a service manual. Besides, being kind of in the boondocks, I doubt there is anybody around that could service the unit.

Does anybody here think it would be worthwhile to spend the time and effort to add insulation and/or figure out a way to recharge the system?