Constant running 2 way Dometic 80L frig.

[photohc]

I have a factory installed 2 way frig in my new Hawk that seems to run all day. Being new at this, I'm not sure if this is normal or not. I would expect that once it reaches the set temp on the thermostat, it would stop then restart upon a rise in temperature, but it seems to run more than normal, depleting my battery. The draw is around 4 amps which is normal according to the manual. The temperature is usually around 39 degrees, so it appears to be doing it's job.
I did note that the exterior ventilation is limited to just two slots cut into the cabinet above the refrigerator to allow the heat to escape into the cabin. Behind the unit is a slotted grill to the outside but is covered with a aluminum blank effectively closing off the grill.
My guess is, the venting is inadequate and causing excessive heat buildup and working against the unit causing the compressor to work overtime to keep the inside cool.
Any thoughts or ideas would be appreciated.

 

[KILR0Y]

photohc,

Quick question: Did you order the extra cooling fan for the fridge? This seems to help my fridge stay really cool, although it does draw extra power and only aids my fridge to cycle off/on (at burner) only a few times more per day. I turn it on/off as needed depending on the outside temperature, and I also feel the top of the fridge/counter-top to see if it's building up excessive heat in that compartment. When it feels hot to the touch on top of the fridge, I cycle the fan on for while to cool that compartment down. I can usually camp for 2-3 days without running the EU1000 genny or the truck to charge the battery back up. For a comparison, one bottle of gas will last me about 4-5 days running all appliances & furnace normally.

One thing I did to help keep the battery charge longer is to order an extra toggle switch for the lower panel (under fridge) that replaced where the "exterior lights" switch was (I didn't order that option). I re-labeled the switch to read "CO2 Detector" and wired that unit so that I could turn it on/off as needed. That unit does take a small amount of battery draw, but this allows me to shut it off at times when I'm not sleeping. Easy 15 minute job that requires only 2 new wire ends. Some may scoff at this but it gives me the flexibility to decide when I have it on or off to conserve battery draw when the camper is not being charged.

Just a thought. I hope my results above, as well as the one suggestion helps you compare and save some battery draw. Others will likely have some good recommendations as well.

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[KILR0Y]

p.s. After a little more thought on my answer above, the pop-up design of FWC does not allow for an ideal refer install, mostly relating to upward venting options as you discuss above. Take steps to mitigate this issue and enjoy the camping! If you want to order a small computer cooling fan (like the factory does) I can snap a few pictures for you of my unit. Had I known how they installed it, I would have saved my $50 and ordered the $4 fan online and installed it myself, although having it done by them was handy.

 

[photohc]

Kilroy, thanks for your thoughts on this. I did not order the cooling fan for this refer and at the time didn't think it was necessary. I removed the exterior vent grill to allow the heat to escape to the outside as a test. I would be happy to get those pictures of the fan install. Where is the on/off switch for that located in you unit?

 

[KILR0Y]

This is the picture of the refer vent and fan location from the outside:

Here is a slightly closer up photo. I can remove the panel and show you better mounting photo's at some point in the future, and you may need to run some wires down to the switch panel, which shouldn't be too hard.

Photo of my switch panel with new CO2 switch installed (prior to re-labeling it):

I believe this is the fan, but will need to measure to be sure.

 

[camelracer]

I had the same problems after installing my Truckfridge. The compressor was running too often and sucking down the batteries. The Truckfridge was a tight fit in the cabinet and I didn't think there was enough air flow across the condenser coils. I installed a vent through the side of the cabinet next to the compressor to improve the flow. Since my camper originally had the 3 way fridge there were 2 outside vents and an exhaust fan but that didn't help the flow across the condenser coil.

I also froze a couple bottles of water in the freezer. This increased the thermal mass next to the thermostat and reduced the on/off cycling. If you don't have a freezer just increasing the load in the fridge should help.

Everything seems to be working much better now.

 

[photohc]

Thank you CamelRacer. Never would have thought loading up the fridge would reduce the cycling. I like the water idea and will try it. Interesting is that FWC did cut out on the side wall for venting to the outside but the actual louvered panel has been covered up to close off any airflow. I may open that up by removing the aluminum panel. Seems it would not hurt. Can you think of any negatives to allowing airflow from the outside. Dust/dirt?

 

[jha6av8r]

I orginally ordered a fan with my 2-way fridge and FWC said it wasn't needed. Only needed with the 3-way so as a result I too do not have venting to the outside. I found my 110L fridge was running all the time when the thermostat was set to 5 or higher. If I turn it down to just under 5, it cycles on and off properly. I did a test with it empty set to just below 5 and with nothing in the fridge it maintained 40 degrees plus or minus a degree depending on how long the compressor had been off.

I was thinking about taking it in to have the thermostate checked because I think it should cycle properly no matter where I have it set.

 

[rotti]

Color me confused.....
My 2012 Hawk with the 2-way 110L fridge has an exterior vent and FWC recommended and I ordered the cooling fan.
In any case my fridge cycles on and is mostly off no matter the setting on the thermostat. I seldom use the fan unless it is extremely warm.

 

[camelracer]

Thank you CamelRacer. Never would have thought loading up the fridge would reduce the cycling. I like the water idea and will try it. Interesting is that FWC did cut out on the side wall for venting to the outside but the actual louvered panel has been covered up to close off any airflow. I may open that up by removing the aluminum panel. Seems it would not hurt. Can you think of any negatives to allowing airflow from the outside. Dust/dirt?

I attached some filter material behind the louvers to slow down the dust, sand and bugs.

 

[Kodachrome]

I installed my 65L 2 way my self in my ATC and did a rather custom job of it. Every part of the fridge except the fan and coil area is sealed off with about 1" of multi-layer Reflectix insulation material and aluminum HVAC tape. The fan and coil are properly exposed to fresh air and no dust gets in. This simply works really well and I don't draw a lot of power at all. My fridge has been on full time since May and pretty much runs off of solar, no puking CO2 in the air for the sake of recreation. I keep it reasonably stocked so that helps too, always some ice-cream and frozen chicken in the freezer, LOL!

Anyway, that is my take on it...

 

[Bosque Bill]

My compressor fridge seemed to run way too much initially when the weather was warm. I talked to FWC and they assured me a separate fan wasn't needed and to check where I set the temperature control. I bought a refrigerator thermometer and placed it on the back wall under the freezer section - I adjust the knob until it settles in the correct temp zone; I think I had it turned too cold initially. I also keep tupperware containers of ice (frozen at home first) in the freezer section as I don't use it for frozen food. Keeping the fridge full of food, drinks, etc. also helps. With all that the compressor seems to run only as needed and things stay nice an cool inside. I also start the fridge empty about 24 hours before I take a trip with the camper attached to shore power, then add already cold food and drinks. The shelf in the door is the warmest place, only use that for juice or non-critical items.

 

[photohc]

Thank you all for your feedback. I'll just need to observe and readjust the thermostat. I may have had too little in the fridge and the thermostat too low. I'll need to add a better thermometer to monitor.

 

[Fitz]

I bought my 2012 Grandby with the ice box option. I then scored on a discontinued Waeco 110L fridge similar to the Dometic 110L for about half of the price. I installed a vent on the side of the cabinet next to the stove with a fan. I wired the fan to the fridge to only come on when the fridge cycles on. I also installed a switch in the vent to disable the extra fan when outside temps are below 80 degrees.

My fridge came with a plastic defrost drip tray under the freezer, removing the tray greatly improved the performance of the fridge. Not sure if the Dometics come with this tray,
By accident while camping one day I had pressed my arm up against the door of the fridge and was suprised at how cold the door was. I removed the door when I got home and slid out the black sheet metal door panel facing and put a layer of Reflex insulation on then reinstalled the panel. Now the door does not fell as cold to the touch.
Hope this helps

 

[Fitz]

I guess i need to work on my picture posting.

 

[photohc]

Fitz, nice job on the installation. How difficult was it to remove the door and panel. I looked at mines and couldn't determine how to dismantle the door.

 

[Fitz]

It was pretty easy. I had to slide the fridge about six inches out of the way of the cabinet to access the top
and bottom swing arm pins that the door swings on. Four screws hold the top swing arm pin, I removed top pin and lifted the door off of the bottom pin. With the door off of the fridge, mine had three screws holding bottom frame molding to the door. I removed the bottom part of the frame and slid the panel out. Again mine is a Waeco fridge and I'm not sure if Dometic changed the design when they took over the company.

 

[jha6av8r]

I installed my 65L 2 way my self in my ATC and did a rather custom job of it. Every part of the fridge except the fan and coil area is sealed off with about 1" of multi-layer Reflectix insulation material and aluminum HVAC tape. The fan and coil are properly exposed to fresh air and no dust gets in. This simply works really well and I don't draw a lot of power at all. My fridge has been on full time since May and pretty much runs off of solar, no puking CO2 in the air for the sake of recreation. I keep it reasonably stocked so that helps too, always some ice-cream and frozen chicken in the freezer, LOL!

Anyway, that is my take on it...

I took my Grandby in today and they basically did this modification. The area under the passenger side grill was opened. Originally the grill was installed but a plate sealed it. They added a lower vent and access door below it. Now fan and coil are exposed to fresh air. The fridge is insulated all around with Reflectix and sealed off so dust and wind stay out of the camper. Looking forward to seeing how it works this weekend.