pianotuna
Regina, SK, Canada
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Hi all,
Last year I added twin computer fans at the top of the fridge chimney. This year I put an adjustable thermostat in series so I could prevent them from running in cold weather.
Does anyone have a suggestion about what temperature I should have them "cut in"?
Regards, Don
Kustom Koach Class C 28'5" 256 watts Unisolar, 875 amp hours in two battery banks 12 volt batteries, 2500 MSW watt inverter.
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Fishinghat
Western Washington, USA
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I installed five old computer fans to the inside of the vent cover some 7 or 8 years ago and turn them on and off manually depending on the weather. I generally turn them on when the weather is about 70 or better. They sure improve the efficiency of the frig.
I like your idea of an adjustable thermostat. I think I'll follow your suggestion and install one.
(I also put one inside in frig. It keeps frost from accumulating on the fins and, naturally, keeps temperatures uniform.)
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Bit Bucket
Brookings, Oregon
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Joined: 04/29/2011
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pianotuna wrote:Hi all,
Last year I added twin computer fans at the top of the fridge chimney. This year I put an adjustable thermostat in series so I could prevent them from running in cold weather.
Does anyone have a suggestion about what temperature I should have them "cut in"?
I installed the fans last year too, if I remember right because of your post about it...
I didn't realize it bothered anything when the temps were down, I too should probably put a thermostat in.
Or is un-necesary power consumption the issue?
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More To See
San Diego Area
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If you only want those fans running when your heating element is on I'd say set it for a fairly high temperature. Maybe 90 degrees. Now if the idea is to also keep the back of the fridge cool in general due to heat build up on the exterior side wall of your rig then maybe set it for 60 degrees or so. I suppose for a really fancy setup you'd measure the outside ambient air temperature and have your fans come on when it was warmer behind the fridge that outside. Just some thoughts that probably won't help you much.
95 Winnebago Vectra 34 (P30/454)
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MEXICOWANDERER
las peñas, michoacan, mexico
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Pianotuna,
Use your handy-dandy IR thermometer plus a fridge thermometer and play around to see when to cut the fans in. If you use an old fashioned dial mechanical contact thermostat for AC, it will work perfectly and the contacts are good for an amazingly high amperage, around 20 or so. I used a 48V. surplus fan in addition to just barely move air across the condenser fins and WOW! The temperature inside the refrigerator (8 CF) Norcold dropped 4C on a 40C hot Mexico afternoon.
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KJINTF
Montana
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Don
I used an "Attic Exhaust Fan" Thermostat which I picked up at Lowes
Adjustable anywhere from about 70 to 120 degrees "F"
It's a siimple finger twist adjustment
I believe it's set to 80 the fans draw about 750ma
Thompson Falls Electronics
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cmarq
CT
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Could anyone post some pics of installation? I would like to do my Pace Arrow, Thanks
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greenrvgreen
open road
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In my experience 75 degrees farenheit is the bottom end of the "grey area", and 80 or maybe 85 is the top. Above that and you'll experience difficulty without a fan, or else your fridge is remarkably better than mine.
I have a Dometic and the flue fans are the only reason the fridge stays cold in the summer. For my install (I don't have pics), I simply removed the top cover of the flue on the roof and peered inside. I then went to Walmart and bought a fan (2, actually) that looked like it would fit, then bolt them in with plenty of foam padding for noise reduction.
The cooling benefit was immediate. If I strain to listen, I can tell the fan is running, so I try not to listen for it. As for the thermostatic actuation, I have a outlet in the fridge alcove that I use twice a year: I plug the fans in in the spring, and unplug them in the fall. All summer my food stays cold!
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pianotuna
Regina, SK, Canada
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Hi all,
Mex--no infra red gun. I do have a remote sensing thermometer monitoring temperatures at the moment.
The thermostat is adjustable from 0 C to 50 C. It does have mechanical contacts but is an old "bulb" style unit. The limit is fixed--and I'm not sure what it is, but it is narrow enough to allow the fans to cycle. It is in series with the switch so I can still manually turn them off if need be.
The issue is not power consumption but rather noise. One of the fans turns at a slightly different RPM than the other...and so there is a rather annoying "surging" that happens. I don't hear it while driving, but at night...well let's just say it is a nuisance.
The other reason is because I run my RV a lot at well below freezing--so in winter time I actually have to heat the outside of the fridge. I'm pleased that the "mask" and fans restrict the heat going up the chimney in winter time. I now have a cube T3 thermostat that operates a light bulb for the winter situation.
I was hoping one of you fine gentleman would have "the ideal temperature". I guess I'll have to wait until the summer arrives (if ever) and dial up a useful temperature.
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pianotuna
Regina, SK, Canada
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Hi Bit Bucket,
No problem so long as temperatures are above freezing. Below that one needs to be cautious.
Bit Bucket wrote:
I didn't realize it bothered anything when the temps were down, I too should probably put a thermostat in.
Or is un-necesary power consumption the issue?
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