Arch my fridge quit working so I decided to do the flip it over and back
upright thing and hope for the best.
>
Having done that the fridge is now sitting in my garage working fine.
>
While I await help to put it back into the GMC I did some temp testing to=
determine where to put a temp activated switch for the fan I am installin=
g
under the coils.
>
Before I began the temp testing I installed a flat piece of galvanized
metal behind the coils in an attempt to help convection move air past the=
coils. The galvanized also provided a location to attach the fan to.
>
The fan I am using is the same as those used in electronics and is about =
4"
square, very quiet. I can't remember the exact draw but it is 12 volts
drawing less than 1/2 amp.
>
All testing was done with both the fridge and freezer doors open. Since I=
don't have a good understanding of how the fridge regulates itself I
thought that this would cause it to run flat out. All testing was done wi=
th
the fridge running on 120 Volts. (it is a propane/120 volt unit)
>
The following temperatures are without the fan I added running.
>
The highest temperature I was able to measure at the upper fins was 92.7
degrees F (70.7 degree F room temp)
>
The highest temperature I was able to measure at the pipe exiting the upp=
er
fins was 111.1 degrees F (70.8 degree room temp)
>
The highest temperature I measured anywhere was 175 degrees F (70.7 degre=
e
room temp) at the point where the refrigerant pipe exits the top of the
tall insulated box (insulated box with propane burner at bottom)
>
I must note that I did not measure the temperatures of the flame exhaust
pipe nor did I measure the temperature of the refrigerant pipe anywhere
inside the tall insulated box (nearer the burner). I am certain that thos=
e
temperatures would be higher.
>
Even the little fan I am intending to use knocked 8.7 degrees F off the
upper fin temperature. (84.0 degrees F [70.7 degree room temp])
>
I also tried to simulate the motorhome enclosure with pieces of plywood
behind and beside the fridge. The fin temperatures dropped a further 3.7
degrees F. (80.3 degrees F [70.8 degree room temp]) I suspect that the
enclosure increased the ability of convection currents to move air past t=
he
warm stuff.
>
Now that I have gone through this I wish I had done some testing prior to=
installing the galvanized on the back of the fins - - - - - - - oh well.
>
Although I tried to be scientific and the instrument I used is a reasonab=
ly
accurate digital unit, there are probably some errors introduced by these=
methods (especially given my limited knowlege of these fridges).
>
One thing for sure, the temperatures in the space surrounding the install=
ed
fridge can get considerably higher than the room temperatures I tested at=
.
For example, I have no idea what the impact to fin temperatures air in th=
e
enclosure of, say 105 degree F might be, but I think I might take a few
more readings once I reinstall the fridge.
>
I don't believe this is the original fridge. I don't know how similar oth=
er
makes or models might be.
>
I certainly can see some advantage to placing the fan in the exhaust vent=
as you are planning since the heat from the fridge can radiate through th=
e
interior partitions surrounding the fridge thereby heating the interior o=
f
the coach (only in the summer though when you don't need it, see Murphys
law #492 :>).
>
One thing I have always done on any RV I have ever owned is if the fridge=
comes out the partitions adjacent get an air barrier and insulation befor=
e
the fridge goes back in to reduce this unwanted heat soak as well as dust=
sucked into the coach through the fridge vents etc.
>
I hope to get the fridge back in Saturday, if I get more temp info I will=
get the exhaust temp and the refrigerant pipe where it leaves the burner.=
>
Regards
>
Gary Zingle
1973 GMC 26 foot
Enjoying another day in Edmonton
upright thing and hope for the best.
>
Having done that the fridge is now sitting in my garage working fine.
>
While I await help to put it back into the GMC I did some temp testing to=
determine where to put a temp activated switch for the fan I am installin=
g
under the coils.
>
Before I began the temp testing I installed a flat piece of galvanized
metal behind the coils in an attempt to help convection move air past the=
coils. The galvanized also provided a location to attach the fan to.
>
The fan I am using is the same as those used in electronics and is about =
4"
square, very quiet. I can't remember the exact draw but it is 12 volts
drawing less than 1/2 amp.
>
All testing was done with both the fridge and freezer doors open. Since I=
don't have a good understanding of how the fridge regulates itself I
thought that this would cause it to run flat out. All testing was done wi=
th
the fridge running on 120 Volts. (it is a propane/120 volt unit)
>
The following temperatures are without the fan I added running.
>
The highest temperature I was able to measure at the upper fins was 92.7
degrees F (70.7 degree F room temp)
>
The highest temperature I was able to measure at the pipe exiting the upp=
er
fins was 111.1 degrees F (70.8 degree room temp)
>
The highest temperature I measured anywhere was 175 degrees F (70.7 degre=
e
room temp) at the point where the refrigerant pipe exits the top of the
tall insulated box (insulated box with propane burner at bottom)
>
I must note that I did not measure the temperatures of the flame exhaust
pipe nor did I measure the temperature of the refrigerant pipe anywhere
inside the tall insulated box (nearer the burner). I am certain that thos=
e
temperatures would be higher.
>
Even the little fan I am intending to use knocked 8.7 degrees F off the
upper fin temperature. (84.0 degrees F [70.7 degree room temp])
>
I also tried to simulate the motorhome enclosure with pieces of plywood
behind and beside the fridge. The fin temperatures dropped a further 3.7
degrees F. (80.3 degrees F [70.8 degree room temp]) I suspect that the
enclosure increased the ability of convection currents to move air past t=
he
warm stuff.
>
Now that I have gone through this I wish I had done some testing prior to=
installing the galvanized on the back of the fins - - - - - - - oh well.
>
Although I tried to be scientific and the instrument I used is a reasonab=
ly
accurate digital unit, there are probably some errors introduced by these=
methods (especially given my limited knowlege of these fridges).
>
One thing for sure, the temperatures in the space surrounding the install=
ed
fridge can get considerably higher than the room temperatures I tested at=
.
For example, I have no idea what the impact to fin temperatures air in th=
e
enclosure of, say 105 degree F might be, but I think I might take a few
more readings once I reinstall the fridge.
>
I don't believe this is the original fridge. I don't know how similar oth=
er
makes or models might be.
>
I certainly can see some advantage to placing the fan in the exhaust vent=
as you are planning since the heat from the fridge can radiate through th=
e
interior partitions surrounding the fridge thereby heating the interior o=
f
the coach (only in the summer though when you don't need it, see Murphys
law #492 :>).
>
One thing I have always done on any RV I have ever owned is if the fridge=
comes out the partitions adjacent get an air barrier and insulation befor=
e
the fridge goes back in to reduce this unwanted heat soak as well as dust=
sucked into the coach through the fridge vents etc.
>
I hope to get the fridge back in Saturday, if I get more temp info I will=
get the exhaust temp and the refrigerant pipe where it leaves the burner.=
>
Regards
>
Gary Zingle
1973 GMC 26 foot
Enjoying another day in Edmonton
