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Better fridge performance

Was going to call this better reefer performance. But changed my mind. Tonight I was out in the coach and it's about that 30 odd something degrees out with a 10-15 mile an hour wind. I heated up the coach and when I walked by the refrigerator I could definitely feel the cold drafts. My coach leaks like a sieve at this area. Blocking off the top gaps, side gaps and bottom gaps at the rear of the fridge would be a no-brainer. I don't do the left-handed cigarette thing but I do enjoy a cold beer.
Leakage adds energy cost both summer and winter and would improve food storage temps inside the fridge. Not to mention the coaches indoor comfort.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: Better fridge performance

Reply #1 –
What exactly would do, Phred? Maybe pack fiberglas around the fridge? Certainly wouldn't want to spray foam although that would stop leaks and insulate. It would also make it difficult to replace unit when necessary. Next owner would be less than happy.
Larry
1996 U295 36'
Build # 4805
Actually we sold it but just like to lurk

Re: Better fridge performance

Reply #2 –
The problem with the OEM 2-way and 3-way refrigerators is they must have adequate fresh air venting to operate.  This means a big hole cut in the side of the coach behind the fridge, and another big hole in the roof above the fridge.  Those 2 big holes can allow a lot of outside air into the coach.  Once inside, it easily moves around the top, bottom and sides of the box, causing the problem you are describing.

As Larry points out, sealing around the box is difficult, due to the tight confines.  In some cases, it might not even be advisable.  Some of the fridge designs require a little "breathing room" around the perimeter to function properly.

Having some way of letting a little fresh air into the coach is a good thing, but too much ventilation is less good, especially in the Winter.  Of course, the ultimate answer is conversion to residential.  When we installed our Samsung I closed off the side and rooftop openings, eliminating the drafts.  The Samsung vents to the front, out the bottom, so it doesn't need the openings to the outside.  It's been functioning perfectly this way, running 24/7 for 3.5 years.  We LOVE it.

If you want to stick with the OEM reefer, you might be stuck with the drafts. 
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Better fridge performance

Reply #3 –
Good thoughts, however, the residential fridge does transfer heat from inside the box to the ambient room air. This must be cooled in summer so, while not significant, it does add to the cost and reduces the presumed efficiency of the fridge.
Larry
1996 U295 36'
Build # 4805
Actually we sold it but just like to lurk

Re: Better fridge performance

Reply #4 –
Quote from: Old phart phred –
Was going to call this better reefer performance. But changed my mind. Tonight I was out in the coach and it's about that 30 odd something degrees out with a 10-15 mile an hour wind. I heated up the coach and when I walked by the refrigerator I could definitely feel the cold drafts. My coach leaks like a sieve at this area. Blocking off the top gaps, side gaps and bottom gaps at the rear of the fridge would be a no-brainer. I don't do the left-handed cigarette thing but I do enjoy a cold beer.
Leakage adds energy cost both summer and winter and would improve food storage temps inside the fridge. Not to mention the coaches indoor comfort.
Phred, your fridge will produce a lot of heat, especially in the summer when ambient temps are higher. The heat from inside the unit, [your beer] is transferred to the coil on the back of the fridge. Air comes in from the side of the coach, up over the coils, transferring heat from the coils to the air, and out the top vent of the coach. If you prevent this flow, it might work in the winter, but not in the summer. Best to seal up areas around fridge inside coach, and leave back of fridge open.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Better fridge performance

Reply #5 –
Quote from: lgshoup –
Good thoughts, however, the residential fridge does transfer heat from inside the box to the ambient room air. This must be cooled in summer so, while not significant, it does add to the cost and reduces the presumed efficiency of the fridge.
I believe we have had this discussion here before.

While your statement is technically correct, it is my opinion that the added heat load from the fridge is SO insignificant that it can be ignored, especially when compared to the total heat gained through the windows, walls, floor and roof. (The windows, especially, when they are single pane like our coach)  The coach always builds up interior heat in the summer, so at some point the A/C units will be required, regardless of what type fridge you have.  I am happy to accept the cost of any slight increase in interior heat in the summer, if I can avoid the cold drafts in the winter by closing off the outside openings.

As to the efficiency of the fridge, how do you measure that?  Residential units are designed to run in enclosed spaces.  Our Samsung has, as I said, run perfectly for over 3 years.  The interior temp never fluctuates, regardless of whether we are running on shore power or inverter.  If the "presumed efficiency" has been reduced by running in a un-vented enclosure, I see no evidence of it.

As I said, this is all my personal opinion only.  Others may have different views, and are welcome to them.  It's all good!  8)
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Better fridge performance

Reply #6 –
You are right Chuck, this has been discussed before. My 81' came with residential ref. from Foretravel and when I bought the '96 Monaco Sig. my wife was very unhappy with it because she lost her refrigerator space and I had to install one of the Samsungs to do the happy wife happy life thing. The '99 had already had the conversion so all is good. The only downside was after about 15 years of use I needed to repair a valve on the one that came in the '81 and had to move it to the living room to make room for the repair. Back to the heating subject, I figure the gain of heat in the winter off sets the need for air in the summer.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Better fridge performance

Reply #7 –
Quote from: Chuck & Jeannie –
I believe we have had this discussion here before.

While your statement is technically correct, it is my opinion that the added heat load from the fridge is SO insignificant that it can be ignored, especially when compared to the total heat gained through the windows, walls, floor and roof. (The windows, especially, when they are single pane like our coach)  The coach always builds up heat in the summer, so at some point the A/C units will be required, regardless of what type fridge you have.  I am happy to accept the slight increase in interior heat in the summer, if I can avoid the cold drafts in the winter by closing off the outside openings.

As to the "reduced efficiency of the fridge", how do you measure that?  Residential units are designed to run in enclosed spaces.  Our Samsung has, as I said, run perfectly for over 3 years.  The interior temp never fluctuates, regardless of whether we are running on shore power or inverter.  If the efficiency has been affected by running in a un-vented enclosure, I see no evidence of it.

As I said, this is all my personal opinion only.  Others may have different views, and are welcome to them.  It's all good!  8)
Chuck, I think a problem could arise according to the design of the residential fridge. If yours vents out the bottom and air can circulate, it will work fine.  But I have seen new fridges that have the passive condensing coil behind the case on the  side of the fridge, behind the surface. Some people think they can make the fridge more efficient and place insulation around the sides. This traps the heat in the condenser coil and does not allow the fridge to radiate that heat to the air. If you are going to an electric only fridge, best to learn the design features first.
The best type of replacement fridge would be one with exposed condenser piping on the back like the original propane one, to use existing ventilation flow, but these types are seldom made anymore.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.