Recharging refigerator fluid

westernman

westernman

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I have a Frigoboat Capri 50F refrigerator which uses a Danfoss BD50 compressor which gets only marginally cool. The compressor runs pretty much the whole time. I suspect it is lacking refrigerant.

Any advice as to how to recharge the refrigerant - I have no clue as to what to put where (or where to get it) and I cannot find anybody in my area who knows either!

Is it just a case of screwing the recharge bottle onto the right place? (and what might that be?)

Thanks for any useful advice.

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The Frigoboat website has an online manual and instructions for recharging including details for accurately diagnosing problems.

SEE HERE
 
The problem is that if as is likely you are low on refridgerant there will be aleak in the system. This will require the leak to be repaired then the whole system must be avacuated (all air sucked out) followed by charging with the correct amount of refridgerant.
Leaks are often identified by a build up of oil stain under the leak. The gas has oil in it for lubrication. Often however it is the compressor itself that leaks if not pipes or condenser/ evaporator.

I like the description in the link but you may find it is illegal to do the work yourself . This was brought on by the international agreement to reduce flourocarbons into the atmosphere. A licensed man should have gas recovery gear. In any case unless you can borrow a vaccuum pump to avacuate the system after you find the leak you may well need a refridgeration technician to come to the boat. (Yeah a real pain)
good luck olewill
 
You must have a Refrigerant Safe Handling & Recovery certification. If you suspect there is a leak on the system then you must not re charge without first locating and repairing the leak.
For what it's worth, the charging point will be on the low pressure side of the system ie between the evaporator (grill) and the compressor. Usually on this type of system it will be a Schraeder type valve.
Normal procedure is to recover what charge is left in the system, draw a vacuum and do a drop test, pressure test with nitrogen, fix any faults and then charge. Most engineers will have a recovery rig that will do all of this automatically (except fix the leak of course /forums/images/graemlins/ooo.gif)
 
Last time this happened to me was with a very old refrigeration unit which had lost gas over many years and did not appear to have a leak. I found a firm that sold secondhand white goods and got their engineer to come and do the necessary. In 1999 this cost about £30 - I did check he was using the right gas! Six years later, when I sold the boat, the refrigration was still very good. About 2 months ago Halfords were selliing gas cylinders for topping up car air cons - about £20 so far as I remember. No use if you have a leak though.
 
Bit like the nonsense recently where, allegedly, the rules said you cant do wiring in your house yourself any more, EEC dont you know, then all of a sudden we find out that you can do it as long as it is according to specs, hmmmm.
My advice is to go and get a can of gas with a charge connector from ebay or his local motor factor and follow the instructions. If the system still has gas in it, it wont need evacuating, common sense dont you know, pressure in system stops air getting in. (simplistically speaking) He could then go round with some soapy water and see if he can find some leaks. Will also prove whether his compressor is shagged or not.
Stu
 
First, we need to get some perspective on this. None of us want to be careless and leak CFC's/HCFC's into the atmosphere. Hence it is best IMO to have the refrigerant properly recovered.

However, with small systems such as boat systems we know this kind of infringement can never be policed.

The correct procedure as has been said, assuming there is a leak, is to recover, leak test, repair and recharge. But are you sure it is a leak and not simply a tired compressor? An engineer will fit his gauges, take running currents of compressors and the like and from the pressure/temp relationship should be able to confirm this for you.

I would not recommend leak testing with soap and water, sometimes if the charge is very low and with small systems no low-pressure switch is fitted, you can pull a vacuum on the suction (low pressure) side. If even a small amount of water enters the system, you have had it! As this droplet enters the TRV or expansion device it would freeze and block it! Thats one of the reasons why we have driers in the system, but they cannot cope with that much!

So you could, and I am not recommending this, release the charge, pressurise with say white spot nitrogen to a high pressure (you may even hear the hiss) remembering this must be an absolutely minute leak or the system would have failed many moons ago. Repair it if you can, evacuate (most people dont own gauges and vac pump), then weigh-in the precise charge. Even then you may find the same problem exists, a tired compressor! I assume you have cleaned the evaporator and condensing coils already, if not do so!

Or, you could take a chance and just squirt some refrigerant gas in the system, make sure its the correct one, if this gets you going then it probably is a leak, you will now be aware of that, and will be obliged to have it repaired to prevent unnecessary discharge of gas!

Best to get a fridge engineer in, he will know what to do and will sort it for you quickly and will have all the necessary equipment!

Best of luck!
 
Hmmm
first of all the OP is an amateur, I could have used technical terms to show how clever I am but I resisted it, The advice I offered was a simple way to figure out what is wrong with the system. £20 of tackle will give a pretty good idea of what is wrong.
Stu
 
Trust me, with a 1st class honours degree and an MSc in this field, not to mention (whoops I am going to) C.Eng, MASHRAE, M.Inst.R and MCIBSE with 30+ years experience, I could have gone a whole lot deeper if I had wanted to show off! Sorry if this upsets you!

Dont need to boast as I sit here on my boat in the sunny Med., retired at 53. Just wanted to impart something useful to the OP! /forums/images/graemlins/cool.gif

Hey, and did I also mention I designed the boardroom air conditioning systems for the HVCA and RUAG and also systems to some of the highest containment medical research facilities in the UK! Better not eh! /forums/images/graemlins/blush.gif

Chill out. none of us need to show off, we are all just here to help with free advice! /forums/images/graemlins/ooo.gif
 
"Chill out. none of us need to show off, we are all just here to help with free advice! "
Really?
/forums/images/graemlins/laugh.gif /forums/images/graemlins/laugh.gif
Stu
 
[ QUOTE ]
you may well need a refridgeration technician to come to the boat. (Yeah a real pain)
good luck olewill

[/ QUOTE ]

Yep. That is the problem. I can't find one who will come to the boat!

I can find some recharge kits on ebay "Duracool" and the like, but I have not found anything in retail here in France - so I suspect you might not be allowed to do it yourself!

I was hoping to find a simple kit I could screw on somewhere, press a button to fill it up, unscrew and all would be fine for a couple more years.

There is almost certainly a leak. It is almost certain to be a really small impossible to find one.

As far as I am aware, the last time anything was done on the fridge was over 5 years ago by the previous owner.

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