Freezer re-gassing - which gas?

Tradewinds

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Question from my cruising friend who's liveaboard in NZ.

Can you ask on the forums what is the best gas to use on a boat for freezing when replacing Freon. 134 is not so efficient as Freon for freezing. I would be interested to know what the view is.

As all my personal experience is back in the days of R12 & I have a Waeco unit nowadays I've got no useful advice to give.

He's quite capable of re-gassing the unit himself - he just needs the advice on which gas would be best to use for a freezer (I didn't know there was a choice :rolleyes:).

Anyone able to help?

TIA
 
Question from my cruising friend who's liveaboard in NZ.



As all my personal experience is back in the days of R12 & I have a Waeco unit nowadays I've got no useful advice to give.

He's quite capable of re-gassing the unit himself - he just needs the advice on which gas would be best to use for a freezer (I didn't know there was a choice :rolleyes:).

Anyone able to help?

TIA

If it is a Waeco unit, the type of gas should be on a label, probably on the compressor.

It is on my compressor, and I think it is R134a in mine (without going to the boat to look).

This, from Wiki:-
Commercial and domestic refrigerators

Commercial refrigerator and freezer units, which go by many other names, were in use for almost 40 years prior to the common home models. They used gas systems such as anhydrous ammonia (R-717) or sulfur dioxide (R-764), which occasionally leaked, making them unsafe for home use and industrial purposes. Practical household refrigerators were introduced in 1915 and gained wider acceptance in the United States in the 1930s as prices fell and non-toxic, non-flammable synthetic refrigerants such as Freon-12® (R-12) were introduced, however R-12 damaged the ozone layer, causing governments to issue a ban on its use in new refrigerators and air-conditioning systems in 1994. The less harmful replacement for R-12, R-134a (tetrafluoroethane), has been in common use since 1990, but R-12 is still found in many old systems today.
 
I don't think the unit is Waeco - it's more likely to be an older type set-up - ie non Danfoss type unit with a separate compressor etc.

I'll ask him.

Thanks.

Ask him WHICH Freon...

From Google.....

If R12

The best replacement for R12 is considered to be R-134a. The chemical name of R134a is tetrafluoroethane and it chemical formula is CF3CH2F. It is a hydrofluorocarbon (HFC) and has zero ozone depletion causing potential and very low greenhouse effect. R-134a is nonflammable and non-explosive and has good chemical stability though it has some affinity towards moisture.



If R 22....

Many manufacturers offer “alternate” refrigerants like R-407C, R-438A and R-422, claiming they can be used in existing R-22 air-conditioning systems. Changing from R-22 to an alternate refrigerant can compromise overall system performance
 
Yes, to offer advice one really needs to know what the equipment is and what refrigerant it originally used. Within Europe and many other countries, it is no longer possibkle to source the older refrigerabts and illegal to recharge with them. There are a number of rep[lacement gases, which will give a slightly reduced performance, but must be selected to suit the seals used in the original set-up. Older R12 equipment, for example had seals which will not withstand the gas and associated oil of a R134a charge. There was a transitional period during which seals suited to modern refrigerants were fitted to systems using R12, though.

Rob.
 
R-134a is not a replacement for R12 - unless you change the oil

RS-24 is a straight drop in for R-12, if the gas is R-22 , RS-45 ( also known as R424a) is the drop in replacement.

Recharging these systems is not always straightforward & in some countries (inc uk ) you need to have a gas handling licence.

http://www.acr-news.com/news/news.asp?id=860&title=Refrigerants:+The+drop-in+centre try this for more info
 
Refrigerants

I am afraid a bit more detail is required to advise a replacement gas as usually Freon is a brand name for the company who traditionally produced R12 which uses a mineral oil charge. If the refrigeration system is a belt driven by engine or electric motor it is sometimes possible to change to a refrigerant with different properties if freezing was a problem on the original one. I would not advise on going down the route of changing the refrigerant as any expansion valves will also have to be changed or at the luckiest reset. A good idea if the unit is of unknown type and is a larger system with expansion valves is to find one of the valves and look at the head of the valve( usually a disk with a small capillary tube coming out and this should have the refrigerant type written on it. If it is an R12 system I would recommend a "drop in" replacement such as fx56 or R409a as these work with mineral oils and have the same operating properties within a tolerance as R12. If it previously had R502 installed then it was designed for low temperature work and should have a suitable "drop in" replacement for use with mineral oil such as r408a or similar. Usually these older systems re sufficiently large that a small loss in performance is not noticeable. If it a smaller danfoss unit one of the R12 "drop in" replacements would be suitable. If you need any more advice PM me.
 
Hi Owen,

Thanks very much for all that.

I'll get more information & come back to you if I may.

It gets a bit ragged because of the time difference with NZ & the fact he's moored in a river without internet 24/7.

Cheers
Nigel
 
R-134a is not a replacement for R12 - unless you change the oil

RS-24 is a straight drop in for R-12, if the gas is R-22 , RS-45 ( also known as R424a) is the drop in replacement.

Recharging these systems is not always straightforward & in some countries (inc uk ) you need to have a gas handling licence.

http://www.acr-news.com/news/news.asp?id=860&title=Refrigerants:+The+drop-in+centre try this for more info

This is all good information however the "gas handling certificate" is not actually a requirement legally as the system is a portable system. Or at least that is the point that has been made in the past and has allowed people to buy refrigerant in the past.
 
Superb forum

Just to say many thanks to all those who responded.

Special thanks must go to Owen Cox who answered my friend's questions (& there were a few!) so comprehensibly. A diamond man :) .

For me, this is what this makes the YBW forum so good.

Thanks again.
 
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