My refrigerator still uses R-12. What are my options?

[Scubaseas]

Originally Posted by Richard Kollmann

Five amps per hour current for compressor and 0.8 amps for brush type condenser fan is normal for that age Frigoboat BD2.5 compressor system.

The correct R12 refrigerant charge by weight is 4.4 ounces. This type system’s cooling performance depends on precise volume of refrigerant plus or minus 20 grams. Ambient air temperature across condenser and condenser efficiency control whether volume of refrigerant is sufficient on this type capillary tube refrigerant system.

After looking at your picture of condensing unit I believe the condenser may be clogged with debris of dust and hair and the old inefficient fan motor should be replaced with a more efficient 4 inch 80 cfm muffin computer fan.

I suggest a non destructive test to determine if problem is condenser cooling or lack of refrigerant is the cause of poor performance. Vacuum what looks like blockage in lower half of condenser air fin coils. Then place any larger fan in the area blowing air towards condenser cooling fins for a 12 hour test. If performance is poorer than before and amperage is less system is low on refrigerant.

I do not recommend using any refrigerant other than Freon R12 if you are looking for extended life or maybe another twenty years. Yes there are many blended unfriendly replacement refrigerants but none as reliable as the original R12 mixed with wax free mineral oil in Danfoss BD 2.5 refrigerator compressor is the only good choice. Ask around and someone will give you a small 10 ounce can of R12.

Remember there is NO Drop in refrigerant to replace R12 refrigerant approved for the BD2.5 compressor.

As usual excellent advice from someone who knows what they are doing. I would add that R406A can be used as a direct drop in if you can not source R12. I would not use it if you had an older style York engine driven compressor. R406A works well but tends to "fractionate" after a couple of years and may have to be replaced. It may also lead to shorter compressor life. It is compatible with the oil and seals that an R12 system uses where R134A is most definitely not. If you want to switch over to R134A you need to remove ALL the system oil, flush and clean the entire system and replace all the rubber seals. Expect a 20% drop in cooling capacity as well unless you increase the size of the evaporator.



Cheers,

Al

[a64pilot]

R12 is still available and will be for I believe quite a long time, it’s not manufactured in most countries, but it was and was widely available to anyone who wanted it in Korea when I was there in 99/00.
The existing supply of R-12 is recycled in the US and as it’s expensive, economics makes its recovery and resale profitable and that has been far more effective keeping it out of the environment than banning it would have been, cause many would have just released it then.

Same with Halon In the US, it’s available and getting more expensive all of the time and it’s very highly recovered and recycled, because there is money to be made recovering and recycling it.

[Joe500]

Originally Posted by Richard Kollmann

Five amps per hour current for compressor and 0.8 amps for brush type condenser fan is normal for that age Frigoboat BD2.5 compressor system.

The correct R12 refrigerant charge by weight is 4.4 ounces. This type system’s cooling performance depends on precise volume of refrigerant plus or minus 20 grams. Ambient air temperature across condenser and condenser efficiency control whether volume of refrigerant is sufficient on this type capillary tube refrigerant system.

After looking at your picture of condensing unit I believe the condenser may be clogged with debris of dust and hair and the old inefficient fan motor should be replaced with a more efficient 4 inch 80 cfm muffin computer fan.

I suggest a non destructive test to determine if problem is condenser cooling or lack of refrigerant is the cause of poor performance. Vacuum what looks like blockage in lower half of condenser air fin coils. Then place any larger fan in the area blowing air towards condenser cooling fins for a 12 hour test. If performance is poorer than before and amperage is less system is low on refrigerant.

I do not recommend using any refrigerant other than Freon R12 if you are looking for extended life or maybe another twenty years. Yes there are many blended unfriendly replacement refrigerants but none as reliable as the original R12 mixed with wax free mineral oil in Danfoss BD 2.5 refrigerator compressor is the only good choice. Ask around and someone will give you a small 10 ounce can of R12.

Remember there is NO Drop in refrigerant to replace R12 refrigerant approved for the BD2.5 compressor.

Richard, thanks for your message and for sharing your expertise. I was going to buy your book so that I could ask you for your advice but you beat me to it. I will try the simple things you suggest before doing "destructive" things like you say such as replacing systems or adding refrigerant. Joe

[Joe500]

Originally Posted by Marathon1150

We have the same Frigoboat system. We recently had to replace the controller and in an amazing stroke of luck, Nuku Hiva Yacht Services had a used one in the spare part bin that had been removed from another boat. We intend to replace the new used controller after checking the rest of the system to be sure that the controller failed because it was old - original to the 1985 boat.

These machines live a hard life in the tropics. We had previously beefed up the insulation while in Mexico putting reflective bubble wrap on the underside of the lid and the bottom of the box. This seemed to help. We have a thermometer remote unit inside the fridge so we can monitor temperature without opening the lid and keep the unit at between 4 and 6 degrees C. In Tahiti we have had to turn the control know to maximum.

I agree with others in the post. If the unit is frosting up you probably don't need coolant (we have had ours checked many times and it has never been necessary to add coolant). I would add more insulation and even put a space blanket on the hull of the boat when sun is shining directly on it.

We also have an Engel which we use as a freezer. When the Frigoboat controller failed, we used the Engel to make ice to put in the main fridge. This worked ok but the fridge was never as cool as when using the compressor.

Hi Nello,

Thanks for your response. It's good to know you have the same fridge. What brand/model remote thermometer do you recommend? Is it battery powered or do you have to run electricity into the icebox? What brand insulation did you add?

Regards,
Joe

[Coolerking]

Originally Posted by Dockhead

I don't think Hot Shot 2 is actually "drop in".


"The potential problems would include liquid floodback and motor overload at high condensing temperatures and loss of liquid seal entering the
capillary tube at low condensing temperatures. Only in a situation where ambient conditions are expected to be relatively constant can using the original capillary tube and undercharging the unit be considered."


-- Honeywell


https://hvac-talk.com/vbb/showthread...t-Shot-2-stuff


I think you need to do some pretty major work including changing the cap tube, to be sure that Hot Shot 2 will work well.


I can't imagine how that could be worth while for a decades old boat system.


Someone advised just using R12 -- I think it's still conceivably possible to find it. Or scrapping it.

I read your link, and I'm not sure where it says hot shot 2 is not a drop in replacement for R12. Typically its 80% of the original R12 charge by weight. We have used it on many systems that have been working perfect now for years with no change to cap tube length, I would love to see some data that supports your statements.

I love to learn.
Of course, the oem refrigerant is always desired, but not always possible.

[rbk]

Originally Posted by RaymondR

Hydrocarbon fueled bombs are the second largest after nuclear. Called fuel in air munitions they were used during the Vietnam war to instantly create helicopter landing zones.

No they are not, just the largest used in Vietnam and non nuclear. Look up ripple rock or Halifax explosion, two of the largest non nuclear blasts on record. Thermobarics constitute a war crime these days, nasty way to die, having the air sucked out of your lungs while burning, you’d be lucky if you were close enough to be killed by the pressure wave first.

[Dockhead]

Originally Posted by rbk

No they are not, just the largest used in Vietnam and non nuclear. Look up ripple rock or Halifax explosion, two of the largest non nuclear blasts on record. Thermobarics constitute a war crime these days, nasty way to die, having the air sucked out of your lungs while burning, you’d be lucky if you were close enough to be killed by the pressure wave first.

The Russians call theirs a "vacuum bomb". Horrible to imagine.

[Jhhastie]

A couple of concerns. 134 is a smaller molecule than R 12. Your system might be prone to increased leaking.

Also, you don't just add refrigerant. If some of your R 12 has leaked out it is replaced with air. Enough air and your system will utilize more pressure. Further enhancing leaking. You must draw down a vacuum to expel the air/R12 mixture and do a total replacement.

[Nicholson58]

Originally Posted by foggysail

If you have the means to reload your fridge...........there is plenty of the stuff on Ebay

Definitely the lowest cost option if the system generally is leak free.

If you choose to replace, get to the Annapolis sail boat show and get show pricing. We bought air cooled Frigaboat 24 volt systems for fridge and freezer three years ago and installed them while at anchor including forming the plates.

Best to decommission using someone who can scavenge the old gas. Guys at the show can probably help.

Conversion of the old system is problematic. Seals, compressor, orifice, condenser all will be incorrect as well as OLD.

[dancor01]

A very simple test to do.

On the compressor you have 2 tubes. The High pressure and the low.
After the compressor as run for like 10 minutes. one of the tube should be hot to the touch, the other cold. If they feel pretty much the same, then you have a problem

After an hour or so it should be very cold.
Few hours later you should see some trace of condensation, even frost.
If you see that, then the system is running properly.


One of biggest misconception about AC. is that it create cold. It is NOT.
It adsorb heat from inside the box, and release it on the outside the box.

[foggysail]

Originally Posted by Jhhastie

A couple of concerns. 134 is a smaller molecule than R 12. Your system might be prone to increased leaking.

Also, you don't just add refrigerant. If some of your R 12 has leaked out it is replaced with air. Enough air and your system will utilize more pressure. Further enhancing leaking. You must draw down a vacuum to expel the air/R12 mixture and do a total replacement.

Maybe. Would you not need to have both the leak and a vacuum created on the low pressure side for that to occur? I don’t think I have ever seen a negative pressure on either the low or high pressure side when testing my car systems but I am no expert. And a small amount of air by itself should just lessen the performance although if humid air entered the system, that could cause an internal ice blockage.

[sdj]

R12 if you can get it, or slight top up with your propane bottle just until the system is stable again.

CO2 systems from new would be ok if they were steel-hull cooled.

[sfnz]

Originally Posted by Dockhead

Your farts are 2.5 oz? That's more than 100 liters of methane. I wouldn't want to be in the same building . . . Even block . .



And 2.5 oz of propane is almost 5 oz of TNT equivalent. You can't compare to how it's used on land, because when it leaks there, it dissipates harmlessly (usually). In a boat, it can't.


Your boat, your life, your rules, but I wouldn't put propane into a boat reefer for anything, much less into an ancient leaky boat reefer.

ok.... heard enough.... go read the label on your WD40 or CRC can re propellant....each has roughly 3 times total fridge charge inside..... and as we know most boats have 1..2...3..4 or more cans on board and as we all know these cans are not marine rated or corrosion protected..... suggest you seriously rethink your misguided phobias re reefers.
Main prob with using anything other than R12 in any unit is degradation of rubber seals. On the danfoss based units I have yet to find one of these couplings that reseals on removal after 2, 3 or more years service why bother re O ringing a part that is a known potential leak source.....get them welded out, no seals = no leaks, and replace the schraeder cap with a 1/4" flare nut and flare bonnet

[TassieBloke]

Too much misinformation here.

As a first, do as Richard says and clean the evaporator as best you can.

If accessible, when running, check all connections for any oily patchs on the piping as this usually associated with leaking refrigerant. Check the rest with a soapy water mixture for leaks.

If no leaks are found, you have basis to start: no leaks, clean evaporator. I couldn't see the photos, so I'm not what type of condenser you have. If air cooled, clean this as well.

Now try to get access to a IR thermometer to check temperatures across the coil. So check the inlet pipe (the small dia of the 2) and the check the larger outlet pipe. Try to do it as close as possible to the evaporator housing. This reading will tell you a lot about what's happening. You are looking for around 7C drop across the coil.
High temp difference can mean low refrigerant.
Low temp can mean too much refrigerant.
No difference means no refrigerant.

There is a lot more, but this is a cheap way to start troubleshooting before looking for R12, putting on gauges or calling a tech etc.

Check the door seals, frost on the coil is usually a sign of tired seals.

Let us know the results, and I'm sure we can help further [emoji106]

[sdj]

Originally Posted by sfnz

suggest you seriously rethink your misguided phobias re reefers.

No one 'seriously rethinks their phobias' regarding anything, it's a lost cause. There's no point trying to fix them. Any aerosol can has a bunch of propane propellant, but they wont hear that.

I'd still feel uneasy about any flammable gas onboard, however, as I should be. At least have a solid army of independant gas detectors.