Cooling fan on Norcold refrig

[bluecolorkat]

We have a new Primetime Crusader 295RST. The small cooling fan behind the refrig stays on all the time, no matter if on AC power or LP. We are dry camping for the next 18 days in Florida and seems I have to run our portable generator a couple times a day to keep battery charged. The unit is only two months old. Anyone else with a Crusader and the Norcold have the cooling fan run all the time?
Maybe I need to add a second battery.

[TURBS]

Fan may run 24/7 if the fridge is turned on.

Some units were thermostatically controlled I think.
You could locate the fan and install a switch.


TURBS
08 duramax tuned n modded, 32bhok Sabre
2015 camping "2 nights"

[Crockett]

The first ones were. If they deleted a thermostat to save money i would not be surprised, seeing how dometic deleted the dehume switch. Be discreet about how you add a switch, i.e. Dont cut a wire just break it at a spade connector. Dont want to loose warranty over it. If your under 90 degrees, just disconnect. Pull the upper side vent and see how it was vented. Check the refer install specs, see if it was done to spec. Refer manufacturers are very specific here to get a good draft on the "chimney" as its known. The fan may be cheaper than good venting labor. Double side vents do work, they struggle in heat. In case Ive broken any forum rules, this message will self detruct in 10 seconds...

[TURBS]

Agree Crockett,
A second 12v battery or two 6 volts should be considered regardless with that many days dry camping.
That fan Altho a draw is not your only draw.
Your fridge requires 12v to run on propane.
Same goes for your hw heater it requires 12v to run on propane.
TURBS
08 duramax tuned n modded, 32bhok Sabre
2015 camping "2 nights"

[B and B]

I changed the one noisy Fan first week we owned the Fiver for 2 quiet fans with slightly more airflow and much quieter performance.

[mike.t]

Don't think the OP is concerned with noise B and B.

[frozen]

Was going to put a switch on my fan until I felt how much heat it was moving. I suspect that my ice cream would just be cream without it.

[bluecolorkat]

Found out what was causing the cooling fan to run all the time. Found that the top baffle was bent down almost closing off upper exhaust vent. It appears that when factory installed refrig and pushed it back it bent this baffle downward almost closing off upper vent. The two cabinets on either side of refrig is very hot. The only way to fix it is to pull refrig and try to straighten baffle or replace.
This should have been caught before it left the factory. I'm dry camping the next 18 days so have to come up with a fix.

[Crockett]

you prolly just saved your cooling unit. might as well say the whole fridge. just remove baffle and operate with top vent door removed, weather permitting...you'll vent fine.

edit: with the cooler weather the top vent removal may not be necessary. can you extricate the baffle??...

[bluecolorkat]

Was able to remove damaged aluminum baffle. Upper vent was pretty much blocked off. It could have been a fire hazard. Will fabricate a new baffle tomorrow so I can continue on this camping trip.

[Crockett]

had a late thought...sort of after the fact. did you say coach was new? it would have been good to document install with pictures. sodium chromate begins to crystalize in the boiler chamber above 210 degrees. the small siphon tube there can get a layer in it(like hardening of the arteries) or block altogether. bottom line...damage may have been done to the core even with the fan. not trying to stir the pot...just stating known facts. should have a good rate of pull down and 60 delta T if operating properly.

[Zolin]

Same problem: here was my remedy on a 4 month old trailer.

I pulled my dometic out and lined the sides of the cabinets with styro board insulation from Home Depot. Also closed the dead space on both sides and top of refrigerator. Mine can be operated in zero inches of dead space. I closed up around the back edges and got a firm seal from the outside (did not close up coils or gas burner).
I then slid the fridge back in to the tighter space. I installed two medium 4 inch cooling fans on the back in place of the super loud single one that came fm factory. I also installed two 5 inch exhaust fans on the upper vent cover with very little space above for heat to get trapped. I removed the plywood baffle that was partially blocking the upper vent. Then ran wiring through the back next to the existing wiring and installed two switches on the front control panel to operate each fan bay.

Fans were high efficiency very low current 12 v fans. Cannot hear them running at all. I know I went overboard but that fridge cools quickly and stays an even 37 degrees. It was a night and day improvement and the exhaust fans activate for approx 2 minutes before shutting off. The other fans only come on when the ambient outside temps reach 95 degrees and shut down after 45 seconds. They will stay off for long periods of time. No more whining fan with continuous run time. No more battery drain, no more 50 degree fridge temps on hot days, no more hot interior cabinets around fridge.....it's refreshing!

[Crockett]

due to potential flammability, i would advise against styrofoam anywhere in cabinet. fiberglass, though messy, is an excellent flame retardant. the ideal chimney piece is radiused flashing behind the condenser coil at the top curved to the top edge of upper vent. a couple fans, to aid natural convection, mounted in standard location is probably best. flashing best probably installed after unit is in unless you get elaborate. the core contains hydrogen gas. that and the presence of a flame means stay as flame retarded as possible since the core could always develop a leak.

[Witch Doctor]

Originally Posted by Jim Olson

We have a new Primetime Crusader 295RST. The small cooling fan behind the refrig stays on all the time, no matter if on AC power or LP. We are dry camping for the next 18 days in Florida and seems I have to run our portable generator a couple times a day to keep battery charged. The unit is only two months old. Anyone else with a Crusader and the Norcold have the cooling fan run all the time?
Maybe I need to add a second battery.

Norcold uses a temp sensor located in the top fins. It will only come on when the fins get hot. I epoxied two fans together next to each other on top and used a double spade to hook the second fan up. Taking the baffle out will create better air flow. I also added a third fan in the bottom of the unit also hooked to the top sensor. When they come on it's really for a short time. Also using propane you will create more heat and the fans will come on more. A second battery would help, Not sure where I got this amp usage chart, but I attached it

[Zolin]

Originally Posted by Crockett

due to potential flammability, i would advise against styrofoam anywhere in cabinet. fiberglass, though messy, is an excellent flame retardant. the ideal chimney piece is radiused flashing behind the condenser coil at the top curved to the top edge of upper vent. a couple fans, to aid natural convection, mounted in standard location is probably best. flashing best probably installed after unit is in unless you get elaborate. the core contains hydrogen gas. that and the presence of a flame means stay as flame retarded as possible since the core could always develop a leak.

Even approved foamboard which has a fire rating and foil backing used in home construction to meet fire code? I didn't state that part. The factory trim around the back edges of the fridge enclosure is uneven cut thin plywood with lots of gaps. Don't see how foam insulating board placed on the opposite side of that trim (toward the front of the fridge) in order to close the gaps could put me at higher risk of flames??? Even the sealed gap has pro grade foil tape all around the trim to eliminate exposure.. That being said, I agree the metal flashing at the top would be a more suitable ventilation solution. Sadly, the original install just had the hot air trapped above the top of the cabinet exposed directly to the underside of the roof of the slideout. All that hot air would move up, then backward and get trapped between the roof and the top of the fridge making it very hot. Now most of the dead space is eliminated, I agree about the fiberglass comment but the flame retardant rating was still within range of fiberglass insulation. I got my idea from an earlier posting which had pics, except that install was done with fiberglass insulation with backing around the edges. Thank you for your comment and concern sir.

[OldCoot]

Originally Posted by Crockett

due to potential flammability, i would advise against styrofoam anywhere in cabinet. fiberglass, though messy, is an excellent flame retardant. the ideal chimney piece is radiused flashing behind the condenser coil at the top curved to the top edge of upper vent. a couple fans, to aid natural convection, mounted in standard location is probably best. flashing best probably installed after unit is in unless you get elaborate. the core contains hydrogen gas. that and the presence of a flame means stay as flame retarded as possible since the core could always develop a leak.

With all the wood around?

[Zolin]

I'm guessing most Rockwood installs are done this way, at least on larger units where the fridge is actually in a slideout. Roof vent installs tend to vent much better. The thin uneven plywood encasement around the back edges leave a lot of gaps for LP and heat to enter around the edges.. I would not even consider placing anything beyond those edges in the coil/condenser/burner area of the back of fridge. The install specifications are explicit about this ventilation area needing to be completely open for air movement.

[Witch Doctor]

Originally Posted by Zolin

Even approved foamboard which has a fire rating and foil backing used in home construction to meet fire code? I didn't state that part. The factory trim around the back edges of the fridge enclosure is uneven cut thin plywood with lots of gaps. Don't see how foam insulating board placed on the opposite side of that trim (toward the front of the fridge) in order to close the gaps could put me at higher risk of flames??? Even the sealed gap has pro grade foil tape all around the trim to eliminate exposure.. That being said, I agree the metal flashing at the top would be a more suitable ventilation solution. Sadly, the original install just had the hot air trapped above the top of the cabinet exposed directly to the underside of the roof of the slideout. All that hot air would move up, then backward and get trapped between the roof and the top of the fridge making it very hot. Now most of the dead space is eliminated, I agree about the fiberglass comment but the flame retardant rating was still within range of fiberglass insulation. I got my idea from an earlier posting which had pics, except that install was done with fiberglass insulation with backing around the edges. Thank you for your comment and concern sir.

I would fill the seems with firer proof caulking same as they use for fire wall penetrations in construction. If you are having a problem with trapped heat at the top in a slide out I would build a scoop to direct it out of the dead area and out the vent. The fan is about 6" below the outlet and coil that would move your air out the vent. And your right units with refers in a slide do not cool as good as a straight vent. That's why extra fans help and the scoop.

[Witch Doctor]

Originally Posted by Crockett

due to potential flammability, i would advise against styrofoam anywhere in cabinet. fiberglass, though messy, is an excellent flame retardant. the ideal chimney piece is radiused flashing behind the condenser coil at the top curved to the top edge of upper vent. a couple fans, to aid natural convection, mounted in standard location is probably best. flashing best probably installed after unit is in unless you get elaborate. the core contains hydrogen gas. that and the presence of a flame means stay as flame retarded as possible since the core could always develop a leak.

Is Hydrogen gas the same as ammonia?

Is ammonia explosive?

Pure ammonia is difficult to ignite and has a very narrow range of flammability. Ammonia is flammable only at high concentrations and under extremely limited conditions. Ammonia vapor that contains oil or another flammable contaminant can increase the possibility of an explosion. However, ammonia will not sustain a flame on its own; ignition of ammonia vapor requires an uninterrupted external flame source.

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[Crockett]

ammonia is boiled off of water. water vapor condenses in the top leaving pure ammonia. this is brought into contact with hydrogen gas which is reacts with the ammonia absorbing heat during the reaction. this compound later is brought into contact with water which pulls the ammonia off of the hydrogen and the process repeats...