Refrigerator Fan, Direction of Air Flow

[FlyboyTR]

After my fiasco with finding all the rat damage to the fridge...I have been going through everything. I am puzzled about the OEM fridge fan and the direction of air flow. Our previous 2720, the air flow was downward (sucked heat off the top and expelled it out the bottom. That seems right for me...

However, on our 3023 it is just the opposite. The fan pushes air upwards. That seems backwards since (IMO) the goal is to remove the hot air from the top and exhaust it away versus pushing cool air upwards and out the top vent and between the roof shells when closed.

So, Which direction is correct? Thanks!

[Kidkraz]

The air should go down, out the hole in the floor.

[Bill]

Agreed.

Bill

[FlyboyTR]

Guys,
Thanks for the confirmation. Down flow was the way our previous TM was. So...Either this was possibly wired wrong (some will run backwards) or the fan itself was installed upside down! I'll be adding that to my every growing list! Thanks again!

[ShrimpBurrito]

Very possible it was just installed backwards. On my 3124, “TOP” is hand written in marker on the top side of the fan hub, so it wouldn’t surprise me there was a time when they not so infrequently were installed upside down.

Dave

[FlyboyTR]

Very possible it was just installed backwards. On my 3124, “TOP” is hand written in marker on the top side of the fan hub, so it wouldn’t surprise me there was a time when they not so infrequently were installed upside down.

Dave

Dave,
Thanks. Interesting! I will either correct the wiring or flip the fan! :)

[Shane826]

The fan blows out, not in!

[Kidkraz]

Yep, it sucks.....the air out. Sorry..just being silly here. :D

[FlyboyTR]

Yep, it sucks.....the air out. Sorry..just being silly here. :D

LOL............................ :)

I was able to clean and flip the fan. Wiring was correct. Also realized there was a large mouse-hole between the intake and exhaust holes in the floor. Also took care of that with a piece of flashing that fit nice and tight in the circular hole. Next step is covering the up the hole in the screen on the intake side.

Dang rats were busy. BUT thankfully...... I have not found the first chewed wire or plumbing in the camper.

We're taking her out for a three day camping trip next weekend. Looking forward to having things cleaned up and all things working properly!

Thanks again to all for confirmation that the fan should be sucking air in a downward direction!

[Wavery]

I never could understand manufacturers trying to force hot air to go down or cold air to go up. Neither one works very well. There's gotta be a better solution.

[Shane826]

I never could understand manufacturers trying to force hot air to go down or cold air to go up. Neither one works very well. There's gotta be a better solution.

When there is no other direction for the hot air to go but down, you don’t have much of a choice!

[Kmikesell]

Hot air rises.... the fan "should" blow the hot air away from the coils at the top of the fridge. On another camping sit (Pop up Explorer) there were many mods to make this process as efficient as possible. Basically you make some ductwork to "force" the air up and out and make that air have to run past the coils. I will see if I can find that mod and post a link here if you are interested.

[Wavery]

Hot air rises.... the fan "should" blow the hot air away from the coils at the top of the fridge. On another camping sit (Pop up Explorer) there were many mods to make this process as efficient as possible. Basically you make some ductwork to "force" the air up and out and make that air have to run past the coils. I will see if I can find that mod and post a link here if you are interested.

That's a bit more challenging on a Trailmanor because the upper rear wall covers the outside fridge vent.

[FlyboyTR]

That's a bit more challenging on a Trailmanor because the upper rear wall covers the outside fridge vent.

Agree... When the TM is closed for towing the fridge has a hard time with natural convection cooling (cool air in the bottom and hot air out the top). The only choice is the downdraft fan.

I still remain puzzled that my fan was installed upside down and blowing upwards. Must have been done at the factory. Crazy stuff!

At least I can thank the rats for putting me in a position where I noticed the airflow problem while cleaning things up! LOL

[Kmikesell]

That's a bit more challenging on a Trailmanor because the upper rear wall covers the outside fridge vent.

True, but how many of us run the fridge when "popped down" as talked about in a previous post. There really is no need to do so, and if you are taking a multiple day trip, keep the food that requires refrigeration, in a cooler (Preferably a good rotomolded one, lifetime is my cooler of choice). On a simple two or three hour trip, a precooled fridge will stay cool.

[FlyboyTR]

True, but how many of us run the fridge when "popped down" as talked about in a previous post. There really is no need to do so, and if you are taking a multiple day trip, keep the food that requires refrigeration, in a cooler (Preferably a good rotomolded one, lifetime is my cooler of choice). On a simple two or three hour trip, a precooled fridge will stay cool.

Valid point. As to how may TM owners run the fridge when rolling...no idea!
However, for me... with our previous TM, we towed it 34k miles in 2.5 years. It ran, closed 6-8 hours everyday while we were rolling down the highway. When covering 300-600 miles a day, I don't want to be unloading and living out of a cooler when I have a fridge that will work 24/7 with the unit open or closed.

Our new to us, Rat Motel, 3023 is getting ready for a 23 day 5k mile trip from Lower Alabama to Montana and back. Fridge will be on 24/7. I pray it does as good as the one in our old TM. :)

The great thing is...we all have many choices available as to how we roll! :)

[Kidkraz]

Have ya thought about naming the camper Remy? Ben? Just saying......:new_all_c:D
Some folks see no issue with running the fridge when closed, but I never saw the need to test fate. I take my hat off to those who have had safe travels and wish them many more safe miles.


https://www.ranker.com/list/list-of-rat-characters/ranker-entertainment

[FlyboyTR]

Have ya thought about naming the camper Remy? Ben? Just saying......:new_all_c:D
Some folks see no issue with running the fridge when closed, but I never saw the need to test fate. I take my hat off to those who have had safe travels and wish them many more safe miles.

https://www.ranker.com/list/list-of-rat-characters/ranker-entertainment

LOL. I had really forgot about all the famous rats! Got to love Rizzo! Thanks.

Travis

[Wavery]

We have always run our fridge on propane while traveling (3 different TrailManors). Never had an issue.

Now we have an all electric (110V) fridge and will continue to travel with the fridge on.

[FlyboyTR]

We have always run our fridge on propane while traveling (3 different TrailManors). Never had an issue.

Now we have an all electric (110V) fridge and will continue to travel with the fridge on.

I've owned campers for 27 years and always ran with the fridge on propane. This also includes both Trailmanors. Never had any real problems doing that.

[coralcruze]

After my fiasco with finding all the rat damage to the fridge...I have been going through everything. I am puzzled about the OEM fridge fan and the direction of air flow. Our previous 2720, the air flow was downward (sucked heat off the top and expelled it out the bottom. That seems right for me...

However, on our 3023 it is just the opposite. The fan pushes air upwards. That seems backwards since (IMO) the goal is to remove the hot air from the top and exhaust it away versus pushing cool air upwards and out the top vent and between the roof shells when closed.

So, Which direction is correct? Thanks!

Wife and I were flippin through the tube and came across your vid. about rat damage to your newly acquired TM. I am so sorry this happened but I am not surprised. I have some info. that may be helpful.

Firstly, the most likely reason that fire started is rats love the flavor of wire insulation. Ask me how I know and I will tell yah that they found thier way into my AC cover through the vent slits :( luckily for us I caught the issue B4 it caught on fire when i climbed on the roof for yearly AC coil maintenance. I could not believe the extent of the damage they caused. I did have to get the ac wiring replaced and some capacitors and the AC still runs like a champ until today. The guys who replaced the wires confirmed my suspicion of rats when they found the nest up there. According to the guys they jokingly added red tastes like cherry and yellow like banana. Lol They sell vent covers that go over these areas with a little enginuity. So looking at your you tube I'd bet the fire started right at the group of wires that melted together and near the flash over areas to the top and side.

Anyway, the direction of airflow out the ref. Compartment most def. should be down and out with the vent opening near the top of the ref. close to the metal finials in the ref. cycle. As for airflow inside the ref. It may not matter as much because it's such a small box. As long as there is a fan in there it would make the stagnant cold air that tends to accumulate down towards the bottom circulate.

Out of curiosity. How are you making out finding components for the ref? From my understanding Norcold discontinued the N300 and N400 units and are no longer fabricating most of the thermostat parts. Also how did you find out that the fan was put in backwards from factory? That's nutz SMH

FWIW, when we travel across country and we know we are going to be on the road for more than a three hour stretch we always put the ref. fan on and it's never been an issue. However, we run it using the battery not propane. The caveat here is when we got the bargman wiring done on the TV we had them wire it so the TV alternator supplies the power and power cuts out when the TV alternator is off. ie: at a rest stop. We also have a battery quick disconnect which we pull when we stop. This way power is not drawn from either the TV or the TM. I Know they never reccomend using the ref. on battery and I normally agree but when the TV alternator is running it supplies plenty of power to recharge the TM battery while in tow. It's never been an issue and to me alot safer knowing there is NO propane flame on back there. Besides there are tunnels that forbid having propane on while traveling through so unless people are pulling over to turn off thier propane tanks and cutting power to thier ref. fans when having to go through a tunnel its just too much to think about. Then yah got to pull off after the tunnel and open the TM up to relight it. To me, I never saw an open source of propane with a lit pilot light as a good option on the road.

[FlyboyTR]

Firstly, the most likely reason that fire started is rats love wire insulation. Ask me how I know and I will tell yah that they found thier way into my AC cover through the vent slits :( luckily for us I caught the issue B4 it caught on fire when i climbed on the roof for yearly AC coil maintenance. I could not believe the extent of the damage they caused. I did have to get the ac wiring replaced and some capacitors and the AC still runs like a champ until today. The guys who replaced the wires confirmed my suspicion of rats when they found the nest up there. They sell vent covers that go over these areas with a little enginuity. So looking at your you tube where you had flame and fire was right at the group of wires melted together.

Anyway, the direction of airflow out the ref. Compartment most def. should be down and out with the vent opening near the top of the ref. close to the metal finials in the ref. cycle. As for airflow inside the ref. It may not matter as much because it's such a small box. As long as there is a fan in there it would make the stagnant cold air that tends to accumulate down towards the bottom circulate. .

Thanks for the response. The fire started because of the gas leak on the line that goes from the thermostat to the burner. Rat urine has basically eaten through it. Enough LP made it to the burner allowing it to light. I assume the leaking LP slowly built up everywhere at eventually the gas reached to the open flame. It was a flashover type fire. Just thankful I went outside to check on things. The electrical had lots of burned paper around them. The smoldering fire melted the wiring...all of which I repaired/replaced.

All of the other components of the fridge are in working order. I was cleaning out the cabinet and happen to turn on the fan and that was when I noticed it was blowing upwards instead of downward.

For 46 years I have used fans inside all the RV fridges. They do help a lot!

[coralcruze]

Thanks for the response. The fire started because of the gas leak on the line that goes from the thermostat to the burner. Rat urine has basically eaten through it. Enough LP made it to the burner allowing it to light. I assume the leaking LP slowly built up everywhere at eventually the gas reached to the open flame. It was a flashover type fire. Just thankful I went outside to check on things. The electrical had lots of burned paper around them. The smoldering fire melted the wiring...all of which I repaired/replaced.

All of the other components of the fridge are in working order. I was cleaning out the cabinet and happen to turn on the fan and that was when I noticed it was blowing upwards instead of downward.

For 46 years I have used fans inside all the RV fridges. They do help a lot!

I see... well thankfully no one got hurt and you were able to catch it in time. That's the most important thing. For us also and I guess every situation is differant. In my case chewed wires was the cause in yours something else. If the fan was on when the fire started would make sense that the gas was carried back down to the flame. Insane...

As mentioned I agree that a fan inside a small box ref. Would circulate the cold air. Just nit sure if it make all that much of a diff. If the fan is on top or bottom. Glad you are able to refurbish and all is not lost.

[Wavery]

If the fan was on when the fire started would make sense that the gas was carried back down to the flame. Insane...

As mentioned I agree that a fan inside a small box ref. Would circulate the cold air. Just nit sure if it make all that much of a diff. If the fan is on top or bottom. Glad you are able to refurbish and all is not lost.

Actually, propane is heavier than air. It naturally seeks the lowest place. He was extremally lucky that it wasn't a huge explosion.

I've seen that happen on boats before. There can be a small propane leak and the gas will pool in the bilge for weeks. Then it finds a source of ignition and the boat goes off like a bomb.

[coralcruze]

Actually, propane is heavier than air. It naturally seeks the lowest place. He was extremally lucky that it wasn't a huge explosion.

I've seen that happen on boats before. There can be a small propane leak and the gas will pool in the bilge for weeks. Then it finds a source of ignition and the boat goes off like a bomb.

I was thinking just that and if the fan was installed backwards, with fan on the fresh air would have been forced into the ref. Box than the fresh air would have created positive pressure forcing most of the propane down and out the bottom vent the fan installed backwards in this case may actually have been a blessing...?

Either way very scary indeed!