Hot refrigerator coils...(Fun Finder)

FWIW, what is happening in the top, condenser coil is condensing pure liquid ammonia- the cooler you can make the coil, the more ammonia is produced. From here the ammonia goes down to the freezer, which contains the hydrogen (or Helium). Due to Dalton's law, which basically states that in a mixture of gasses, the total pressure is the sum of each gasses partial pressure, and hydrogen has a very low partial pressure, lower than ammonia, so the liquid ammonia evaporates, which takes requires heat, which comes from the inside of the box.

So, the evaporator coil will be the hottest, but it is where the most heat needs to be removed (other than inside the box :) )

Fans use a t-stat that is attached to the condenser fins.
Based in fin temp the t-stat closes to start fan(s) and opens to stop fan(s)

Typical temps used are 130*F (close) and 115*F (open)----that is HOT

Other temp range t-stats are available.

As Chris stated........the more 'heat' that can be removed the more ammonia vapor can be condensed into liquid ......more liquid ammonia the colder the freezer and then more heat absorption left for food section.

Airflow.......its all about airflow (and how/where that airflow is directed)

Bad advice and even irresponsible.

Installing fans and wires in either end of heat vent violates fire safety codes. You can't (well you can but you shouldn't) run electric wires inside heat vents and duct works.

If wire insulation catches fire, and blower is running, you are creating a blow torch.

Unless you use specially insulated wires which are fire retardant/fire rated.

This item is not even available for the general consumer, let alone RVs.
They are mostly available for fabricating furnaces, stoves and jet engines.

The installation instructions for the Dometic 7401L (smaller sort of RV fridge) include using a baffle below the upper fins so the cool air from the lower vent will pass through the fins on the way up to go out the upper vent.

In some RVs you have a wide space behind the fridge so the cooler air rises up right past the fins and out the roof vent without going through the fins. The baffle stops that.

In some cases a fan can help push/pull the cooler air up. Goodness knows how it can all work down there in Arizona right now! :( What "cool air" coming in the bottom vent?

happycamper002 wrote:
Bad advice and even irresponsible.

Installing fans and wires in either end of heat vent violates fire safety codes. You can't (well you can but you shouldn't) run electric wires inside heat vents and duct works.

If wire insulation catches fire, and blower is running, you are creating a blow torch.

Unless you use specially insulated wires which are fire retardant/fire rated.

This item is not even available for the general consumer, let alone RVs.
They are mostly available for fabricating furnaces, stoves and jet engines.

We're not talking about heating ducts here, this discussion is about the refrigerator cooling system that is vented to the outside. A LOT of units come from the factory with cooling fans to help circulate cooling air behind the refrigerators.

happycamper002 wrote:
Bad advice and even irresponsible.

Installing fans and wires in either end of heat vent violates fire safety codes. You can't (well you can but you shouldn't) run electric wires inside heat vents and duct works.

If wire insulation catches fire, and blower is running, you are creating a blow torch.

Unless you use specially insulated wires which are fire retardant/fire rated.

This item is not even available for the general consumer, let alone RVs.
They are mostly available for fabricating furnaces, stoves and jet engines.

fire safety codes.. hmm.. well I doubt the rv was even inspected let alone build to any codes.. LOL

I'm referring to those who are advising installing fans. Of course you need to remove heat in the condenser portion of any cooling system. This heat that is absorbed at the evaporator end needs to be removed by fans but they are not located in the vents.

Go back and reread the other posts.

happycamper002 wrote:
I'm referring to those who are advising installing fans. Of course you need to remove heat in the condenser portion of any cooling system. This heat that is absorbed at the evaporator end needs to be removed by fans but they are not located in the vents.

Go back and reread the other posts.

Norcold & Dometic have ventilation kits which include FANS and baffles for use in the outside compartment

Factory installed fans on fridges in slide outs are standard

Several aftermarket companies have fan kits for installation

This has been a routine occurrence for many years.......All of these companies have Teams of Lawyers

ARPC LLC fans for fridges

(YAWN)... Ignore him.. all he does is pick fights with zero information to back up these rants

Old-Biscuit wrote:
Fans use a t-stat that is attached to the condenser fins.
Based in fin temp the t-stat closes to start fan(s) and opens to stop fan(s)

Typical temps used are 130*F (close) and 115*F (open)----that is HOT

Other temp range t-stats are available.

Good point and sometimes those TStats stick and do not operate properly. My unit cam with one fan. I added a second. Gotta remove that heat.