Hot refrigerator coil question????

[wantostream]

I'm starting to have probles with my refreigerator. I had it checked at a repair facility which seems to be pretty reputable. I cant get the fridge portion to go down in temperature enough. They put a fan in today for a few hours and the fridge temperature was perfect. They suggested to add a fan on the backside as I've read about in other posts. Before going this route I'd like to know if it is normal that the black coil or cooling unit be so hot. I can put my hand on it for only a couple of seconds.
Any help appreciated

[Jammer]

Yes they get hot. Mine came with a fan and it runs all the time in hot weather. If you don't have one you should get one.

[wantostream]

Do you have to turn it on or is it automatic?

[lewster]

Originally Posted by wantostream

I'm starting to have probles with my refreigerator. I had it checked at a repair facility which seems to be pretty reputable. I cant get the fridge portion to go down in temperature enough. They put a fan in today for a few hours and the fridge temperature was perfect. They suggested to add a fan on the backside as I've read about in other posts. Before going this route I'd like to know if it is normal that the black coil or cooling unit be so hot. I can put my hand on it for only a couple of seconds.
Any help appreciated

Gas absorption refrigerators work on heat.......so your absorber coils and boiler tube will be HOT to the touch. No problem there.

What is happening is your condenser coil is overheating (getting hotter than the spec operating temperature) and degrading the chemical reaction that goes on inside of it where hot ammonia mixes with hydrogen creating a very cold reaction. This is why your refer gets cold!

You can do a couple of things:

1. easiest: place a 12 VDC cooling fan at the bottom of the fridge pointing up at the condenser coils

2. midway: remove the top vent on your roof and place 2-3 computer muffin fans (12 VDC) in the vent stack, sucking the air out of the vent. This will do a better job of keeping the condenser from overheating. You can add a switch or thermo-disc to control the fan operation. I had both in my CCD.

3. most difficult: remove the fridge and add a couple of fans right underneath the condensed coils. Many new, larger RV fridges now come set like this from the factory. They use the thermodisc attached to the first fin from the boiler tube entry as a temp guide.

Your move..............

[wantostream]

Thanks alot Lew, very clear explanation.

[wantostream]

[QUOTE=lewster;873922]Gas absorption refrigerators work on heat.......so your absorber coils and boiler tube will be HOT to the touch. No problem there.

What is happening is your condenser coil is overheating (getting hotter than the spec operating temperature) and degrading the chemical reaction that goes on inside of it where hot ammonia mixes with hydrogen creating a very cold reaction. This is why your refer gets cold!

You can do a couple of things:

1. easiest: place a 12 VDC cooling fan at the bottom of the fridge pointing up at the condenser coils

2. midway: remove the top vent on your roof and place 2-3 computer muffin fans (12 VDC) in the vent stack, sucking the air out of the vent. This will do a better job of keeping the condenser from overheating. You can add a switch or thermo-disc to control the fan operation. I had both in my CCD.

3. most difficult: remove the fridge and add a couple of fans right underneath the condensed coils. Many new, larger RV fridges now come set like this from the factory. They use the thermodisc attached to the first fin from the boiler tube entry as a temp guide.


Forgot to ask Lew, since you seem to know alot on this subject, in my case why is the freezer portion working properly?

[Jammer]

Originally Posted by wantostream

Do you have to turn it on or is it automatic?

It's automatic. I believe there are temperature sensors. It doesn't run in cooler weather.

[nti06]

The condenser coil on the back of any fridge is what actually sheds the heat from inside the fridge. condenser coils get pretty hot. Which can give you an idea of just how much quantity of heat a refrigerator is removing from inside it.
If you can move air over the condenser coil, the fridge will cool better. If you could vent that heat outside, thats less heat for your a/c to have to remove from inside the trailer.

[lewster]

[QUOTE=wantostream;873940]

Originally Posted by lewster

Gas absorption refrigerators work on heat.......so your absorber coils and boiler tube will be HOT to the touch. No problem there.

What is happening is your condenser coil is overheating (getting hotter than the spec operating temperature) and degrading the chemical reaction that goes on inside of it where hot ammonia mixes with hydrogen creating a very cold reaction. This is why your refer gets cold!

You can do a couple of things:

1. easiest: place a 12 VDC cooling fan at the bottom of the fridge pointing up at the condenser coils

2. midway: remove the top vent on your roof and place 2-3 computer muffin fans (12 VDC) in the vent stack, sucking the air out of the vent. This will do a better job of keeping the condenser from overheating. You can add a switch or thermo-disc to control the fan operation. I had both in my CCD.

3. most difficult: remove the fridge and add a couple of fans right underneath the condensed coils. Many new, larger RV fridges now come set like this from the factory. They use the thermodisc attached to the first fin from the boiler tube entry as a temp guide.


Forgot to ask Lew, since you seem to know alot on this subject, in my case why is the freezer portion working properly?

Originally Posted by nti06

The condenser coil on the back of any fridge is what actually sheds the heat from inside the fridge. condenser coils get pretty hot. Which can give you an idea of just how much quantity of heat a refrigerator is removing from inside it.
If you can move air over the condenser coil, the fridge will cool better. If you could vent that heat outside, thats less heat for your a/c to have to remove from inside the trailer.

That works for compressor type refrigeration units. This is a gas absorption unit and does not work in the same way............

[Bluto]

There are little solar panel run fan available too. Valtera makes one such model. Just a small fan for behind the fridge and a small solar panel for the roof. Only operates when the sun is shining on the trailer. A switch can be added to turn it off in cool weather.