Using a typical house refrigerator, has anyone ever ducted the hot air from the condenser to the outside to save of AC loading. Or maybe relocated the condenser outside the living area?
Kenny
Typically a house hold type refrigerator doesn't put out that much heat that only one roof top A/C could easily overcome. I wouldn't worry about it. Good Luck, TomC
Hi Kenny,
If it is hot enough to use the AC, aren't you going to pull into the bus an equal amount of hot air that the refridgerator duct exhausted?
My bus uses a 'household' type unit and I haven't noticed a problem.
RV type fridges pull in outside air at the bottom and vent the air out the roof generally. I suspect this might work with a household fridge, but I'm not sure it is worth the effort to potentially add more leak points to the bus.
There is a trade off.
The hotter the air is going over the condenser coils, the harder the fridge has to work to cool the insides.
If the fridge is adding heat to inside the coach, the A/C will have to work harder to overcome that added heat load.
However;
You want some fresh air inside the coach anyways, so why not put the exhaust in a location that takes the hottest air out, & locate the intake so that it is collecting the coolest air available?
Adding insulation to the outside of the fridge & spacing the condenser further away to allow more insulation there will reduce the run time of the fridge which also reduces the heat load inside the bus. . . .
Have fun with the possibilities! ;D
Thought was some sheet metal ducting on each side of the condenser. Two flexible hoses. One for fresh cool intake air from outside and the other for hot exhaust air from the condenser back to the outside. All air is exchanged from the outside. No drafts, no lost of inside air.
You would be surprised how much heat is generated by a household refrigerator. We spend much money and time insulating, sealing and double pane windows to keep cool in and heat out. Why not start looking at heat generated from within?
Kenny
Most refrigerators will not work over 90 degrees of heat. If you duct the refrigerator from the outside, there is the possibility that if you're in the desert, you could be at close to 120 degrees with road heat kicked in. On the other hand if you're in winter situation, the refrigerator compressor could freeze up. Either way, just keep with using the interior air-that's what the refrigerators are made to do-run at the same temperature that is comfortable to us and with inside air.
To make the refrigerator work with outside air, you would need a remote condensing unit with at least double the condensing coil area with fan to compensate for the hot air during summer (read lots more electrical drain), and a thermostatically controlled compressor crankcase heater for the winter. These compressor units are made (think at a market) and you'll find that they are in the several thousands of dollars. Just not worth it. Good Luck, TomC
I have a 22cf household fridge in my bus and it does put out some heat. I also have a 32 inch flat screen tv that puts out a lot more heat than the fridge. Oh the price we pay for our comfort items. I will put up with the heat and let the air conditioners do there work. Good busn' Wilbur
Quote from: Kenny on March 30, 2010, 08:27:30 AM
Why not start looking at heat generated from within?
Kenny
Yes, look at the total picture. Some things will look good at first, but as more details surface, a compromise must be made.
Some don't care how efficient things are. Some won't put forth the effort if they see no benefit. Others appreciate the elegance of a total plan that works well together.
That is the great thing about this hobby, we each get to do it our own way. ;D
Tom is right. If the frige uses inside air to cool the condenser coils it will be more stable.
It is a trade off, you either cool the frige cond with AC cooled inside air or use more frige power using outside hotter air.
In cold weather you will gain inside heat and the frige will be more stable. Very cold air on the frige cond makes it run less and the frige interior warmer!! I have this problem every winter with my shop frige.
Quote from: gus on March 30, 2010, 06:51:59 PM
In cold weather you will gain inside heat and the frige will be more stable. Very cold air on the frige cond makes it run less and the frige interior warmer!! I have this problem every winter with my shop frige.
We had that problem last winter (longest cold winter on record in Florida). The coach sets in our unheated shop with no heat on in the coach. The house type refigerator is never shut off. The refrigerator stayed so cold that the thermostat would not call for the compressor to run, which resulted in the freezer compartment warming up. Both compartments use the thermostat in the refigerator compartment. Jack
we dont have ours venting to the outside like the propane units but maybe you could isolate the intake and vent up thru the roof like they do. we have a screened closable 2x6 vent under the fridge coils from the bay below. there is also a side vent in the foward wall 8x10 hidden by a angled mirror and there is 2" clearance at the top of the fridge and they gally vent is just above that area. we never have had a problem with cooling or built up heat (at least from the fridge ha ha)
The 14cf Summit refrigerator I'm thinking on using uses an average of 440,000 watts per year. Divide that by 365 then by 24 and you come up with just over 50 watts per hour-not much heat to get rid of. Good Luck, TomC