Cooling a fridge compressor - I have a spare seacock nearby.

[Rikds]

Actually I have a bronze through hull containing a very old depth sounder transducer. It is about 1.25 metres from where I am hoping to install a fridge compressor (probably Isotherm). There is another one on the opposite side of the hull. I don't want to go down the full keel cooling system but I wondered if anyone had a suggestion on how I might use this fitting. I'm currently planning on a standard air cooled installation but thought it might be possible to incorporate the through hull to improve cooling.

 

[Graham_Wright]

My Frigoboat fridge has a cintered bronze hull fitting for the heat exchanger. Water is much better than air.

 

[RupertW]

We also have a through hull. - I think Frigiboat to match the compressor. They just replaced the saltwater tap inlet with this fitting so both now work.

 

[lustyd]

Emily and Clark's adventure have some videos about water cooling. He uses a heat exchanger coil with a through hull. Here's one about his air conditioning but he also shows his fridge in other videos and goes into a lot of depth.

edit: This one may be more relevant to your use

 

[William_H]

There would be no practical way to cool the compressor apart from fan which is recommended. My guess is that you have a fridge system that has gas already in place so would be more trouble to fit a through hull evaporator (in lieu of air cooled) though I think they are very good as above described. if you don't have a gassed system then yes fit a through hull gas cooler and get the system evacuated and gassed. ol'will

 

[luke collins]

It’s a lot of trouble to go to if only using in the UK. You would need a heat exchange, strainer and pump set. Most modern fridge systems hack 40 oc now and run on 134a or equal that works well in high ambient with fan assistance to the condenser. The compressor are logic controlled and variable speed and I believe some slow down if pressures get to high to limit the THR and power to maximise life span etc. If it’s in a hot place may be bring some ducted vent of cool air to the unit or extract if possible.

 

[luke collins]

Also for info the compressor is suction gas cooled so windings are cooled by the cold return gases with a small around of air cooling from the fan. They run pretty hot but should not need any aditional cooling around the body. They only produce a few hundred watts of heat from the condenser hence why air cooling is adequate normally

 

[Rikds]

There would be no practical way to cool the compressor apart from fan which is recommended. My guess is that you have a fridge system that has gas already in place so would be more trouble to fit a through hull evaporator (in lieu of air cooled) though I think they are very good as above described. if you don't have a gassed system then yes fit a through hull gas cooler and get the system evacuated and gassed. ol'will

Currently I only have an ice box, 80 litres. The boat is in W Brittany where we cruise. 6 bottles of frozen water last a week (still a little ice in one bottle in this time).
So I plan to install a fridge plate in the built in box and mount the compressor close bye under the sink.

 

[vyv_cox]

If you are buying new it makes sense to buy a water cooled unit, as said in several posts, the type that has the heat exchanger in the seacock. Far more effective than air cooling with the bonus that the compressor unit can be located anywhere rather than dictated by most effective airflow.

My fridge is a custom conversion with a water cooled condenser replacing the original air cooled one. In Greek summer temperatures it is highly effective, even in sea at 30 C.

 

[Rikds]

Very helpful input everyone, many thanks. I wish I'd measured the diameter of the old transducer tube before coming home!

 

[Rikds]

Emily and Clark's adventure have some videos about water cooling. He uses a heat exchanger coil with a through hull. Here's one about his air conditioning but he also shows his fridge in other videos and goes into a lot of depth.

edit: This one may be more relevant to your use

Great videos, hope I never have to get into it as deeply!! Bit beyond my comfort zone!!

 

[Rikds]

If you are buying new it makes sense to buy a water cooled unit, as said in several posts, the type that has the heat exchanger in the seacock. Far more effective than air cooling with the bonus that the compressor unit can be located anywhere rather than dictated by most effective airflow.

My fridge is a custom conversion with a water cooled condenser replacing the original air cooled one. In Greek summer temperatures it is highly effective, even in sea at 30 C.

Hi Vyv, many thanks for that, your input always invaluable. My ex-students still visit your website!! I'm really hoping that for West coast Brittany the air cooled version might do the job. Huge cost differences!!

 

[lustyd]

Great videos, hope I never have to get into it as deeply!! Bit beyond my comfort zone!!

The skills he talks about are pretty straightforward, I built a system quite easily just from watching that and some soldering/brazing videos and a little practice. The real issue is that you can't easily buy the gas without certification in most of the world now, even the US is planning to crack down on it so the little cans he shows won't be available much longer.
The vaccuum pumps are also changing, the cheap ones are no good as they don't do gas collection for recycling