12/24 Volt Boat Refrigerator’s Poor Performance Possible Causes

[Tbaker]

Originally Posted by Richard Kollmann

Without knowing what your compressor's preset speed is set for I would recommend adding Pure R134a refrigerant slowly until unit is drawing 5 amps and no more. Very slow leaks on Frigoboat units are do to using an actual flow moving Oring seal in each of the line connectors. See Frigoboat web site to obtain correct special seal.

Refrigerant low pressure in picture is the black or green cap above compressor dome. If after adding refrigerant and waiting a while evaporator's surface area does not display frost over 85% of its surface add a small amount of refrigerant. Too much refrigerant in system will display frost on return line towards compressor and compressor may not run the next time it tries to start.

Hopefully you did not add any moisture when servicing system, if so the hissing sound in evaporator will stop and the frost cover will disappear.

My Frigoboat Keel Cooler has a smart speed controller that I can override in manual mode. Is it best to leave it in Automatic when doing a recharge or slow manual?



You say the low pressure port is above the compressor dome so I assume it is the one on the horizontal tube. I attached a picture with an arrow pointing to the port, have I got that right?


When I see plate frosting what psi should I see on my guage so I don't overfill?

[Richard Kollmann]

Low pressure will vary based on evaporator temperature and compressor speed on this system. Six to 8 psi ten minutes after compressor start up is in the ballpark but low pressure starts to drop after 20 minutes. If after 40 minutes with a standard thin plate evaporator most of evaporator will be covered with frost regardless of compressor speed. It is smart to check frost line next day to verify correct refrigerant charge and no frost outside refrigerator box on line returning to compressor. Plus or minus 15 grams on that unit will affect its energy efficiency, a little less refrigerant is better than too much.

Yes picture arrow is pointing to low pressure servicing connection.

[Anna Sail]

I'm rather surprised, Richard, that you're giving advice on how to handle refrigerant. My understanding is that one must be a licensed professional when it comes to charging and recharging a system. Of course, there are many DIY sailors out there who do such things, but this gentleman you've counseled doesn't appear to be one of them, based on his simple questions. Maybe times have changed, even though these high-pressure systems haven't.

[rslifkin]

Originally Posted by Anna Sail

I'm rather surprised, Richard, that you're giving advice on how to handle refrigerant. My understanding is that one must be a licensed professional when it comes to charging and recharging a system. Of course, there are many DIY sailors out there who do such things, but this gentleman you've counseled doesn't appear to be one of them, based on his simple questions. Maybe times have changed, even though these high-pressure systems haven't.

It depends on the refrigerant. You don't need to be licensed in the USA to buy R134a or charge a system with it. You only need a license to recover refrigerant from a system or to buy a large quantity. Many other refrigerants do require licensing though.

[Richard Kollmann]

Originally Posted by Anna Sail

I'm rather surprised, Richard, that you're giving advice on how to handle refrigerant. My understanding is that one must be a licensed professional when it comes to charging and recharging a system. Of course, there are many DIY sailors out there who do such things, but this gentleman you've counseled doesn't appear to be one of them, based on his simple questions. Maybe times have changed, even though these high-pressure systems haven't.

You are correct about the legal intent of the clean air act but the EPA rules have been abated in many areas by those overseeing these regulations. I followed these regulations as they were in development in the US federal registry and was disappointed in the lack of recommendation from the marine refrigeration industry. Legally the regulations state none of the pre-recharged ice box conversion units are allowed to be shipped with refrigerant if lines are connected on installation. The final rules were developed around special industry organizations. Millions of tons of ozone depleting CFC refrigerants have been eliminated but the replacements for CFC and HCFC are now considered a cause for global warming.

We must do our best to limit venting any refrigerant into the air. I believe it is acceptable to top off a system containing less than 5 ounces of refrigerant after five years of operation. The alternative refrigerants containing flammable properties or even CO2 are not ready for small 12 volt boat refrigeration now.

[Coolerking]

Originally Posted by Anna Sail

I'm rather surprised, Richard, that you're giving advice on how to handle refrigerant. My understanding is that one must be a licensed professional when it comes to charging and recharging a system. Of course, there are many DIY sailors out there who do such things, but this gentleman you've counseled doesn't appear to be one of them, based on his simple questions. Maybe times have changed, even though these high-pressure systems haven't.

All I can say Karen is this.

De minimis.

Look it up.