Isotherm 85 two way refrig...do you need vents?
- Thread starter TahoeT
- Start date
billharr
Senior Member
When I did my shell build out I was going to go without vents. Talking to Stan at FWC he said you need a vent, they did on with out and had problems. I have two exhaust fans that run off a thermostat, help with how well the DC fridge works. I only have a top vent.
I believe an unvented compressor refrigerator is going to work harder/consume more amps than one that is vented. A computer fan seems to be a plus as well.
Always go to the manufacturer to get this information:
http://newcontent.westmarine.com/documents/pdfs/OwnersManuals/BBQ_APPLIANCES/Indel%20Cruise%20Owners%20Manual.pdf
from pg. 48:
4.2 Ventilation
[SIZE=10pt]It is extremely important for the compressor/condensing unit located behind the refrigerator to be well ventlated so that the fresh air can enter at the bottom and pass behind the refrigerator, with the hot air being allowed to escape from the top or sides (Fig. 1). The illustrations (Fig. 2-3) show an example of how the refrigerator[/SIZE][SIZE=10pt]housing should be set.[/SIZE]
http://newcontent.westmarine.com/documents/pdfs/OwnersManuals/BBQ_APPLIANCES/Indel%20Cruise%20Owners%20Manual.pdf
from pg. 48:
4.2 Ventilation
[SIZE=10pt]It is extremely important for the compressor/condensing unit located behind the refrigerator to be well ventlated so that the fresh air can enter at the bottom and pass behind the refrigerator, with the hot air being allowed to escape from the top or sides (Fig. 1). The illustrations (Fig. 2-3) show an example of how the refrigerator[/SIZE][SIZE=10pt]housing should be set.[/SIZE]
Stan@FourWheel
Senior Member
We did it all 3 ways in the beginning, when first installing the compressor refrigerators.
1. No vents.
2. One side vent.
3. Two side vents.
With No vents ... most customers were mentioning their refrigerator compressor never shut off. Just ran and ran. They'd pull the refrigerator out about 1/2 way from the cabinet and the compressor would stop. They installed the side events and the compressor would come on and off as needed, and would not run continuously.
This might not be the case with all refrigerators, but it is what we were hearing from out customers with the refrigerators we were installing back then.
Vents when properly installed, and making sure the cabinet is properly sealed up around the refrigerator once installed (keeps the outside air from coming inside the camper), seems to work well.
1. No vents.
2. One side vent.
3. Two side vents.
With No vents ... most customers were mentioning their refrigerator compressor never shut off. Just ran and ran. They'd pull the refrigerator out about 1/2 way from the cabinet and the compressor would stop. They installed the side events and the compressor would come on and off as needed, and would not run continuously.
This might not be the case with all refrigerators, but it is what we were hearing from out customers with the refrigerators we were installing back then.
Vents when properly installed, and making sure the cabinet is properly sealed up around the refrigerator once installed (keeps the outside air from coming inside the camper), seems to work well.
JaSAn is correct, best to check the manual. Also useful for checking someone else's installation or repair work.
Perhaps the discrepancy is "venting" vs "venting to the outside". A traditional 3 way fridge requires the harmful combustion gases produced from burning LPG to be expelled away from the living area. And may also require combustion air to come from the non living area. This is often accomplished within the venting space at the rear of the fridge using an upper and lower opening in the camper wall to the outside.
If I was building a camper I'd look closely at a 2 way, in part because of the possibility to vent internally to the living space. One, to eliminate a hole in the exterior envelope and two, to utilize the "waste heat" for some cabin heating, particularly at night.. But the idea may be practical only in cool weather.
Perhaps the discrepancy is "venting" vs "venting to the outside". A traditional 3 way fridge requires the harmful combustion gases produced from burning LPG to be expelled away from the living area. And may also require combustion air to come from the non living area. This is often accomplished within the venting space at the rear of the fridge using an upper and lower opening in the camper wall to the outside.
If I was building a camper I'd look closely at a 2 way, in part because of the possibility to vent internally to the living space. One, to eliminate a hole in the exterior envelope and two, to utilize the "waste heat" for some cabin heating, particularly at night.. But the idea may be practical only in cool weather.
Thanks for the responses. I did call the manufacture and they told me to vent the unit as did FWC. The camper/frig happens to be at my RV repair shop which is 40 miles away. Therefore, I didn't have access to the instructions, specs, etc. I had to wait to call the company because they were closed for the night and my RV shop need an immediate answer, so I submitted the post knowing that this forum would have the answer. Great people on this forum...thank-you! Tim
PokyBro
Senior Member
Hello TahoeT,
I installed an Isotherm 130 L in my rig, and when I looked at the manual, it suggested an outside vent, and a path across the compressor, then venting to the inside. Keep in mind this might be more for a marine application. But that's how I configured mine. Below are some photos from my build that show how I cut the vent holes. I know FWC uses the same two exterior vents on the 2 way compressor fridge that are also used on the 3 way, but not sure why, there's nothing at the bottom of the two way fridge. Maybe it's just to let a large volume of air in behind the back of the fridge. I have those vent covers if I ever decide to take the same direction.
Anyhow, my arrangement seems to work fine, and you can feel warm air from the compressor come through to the inside of the cabin. It's not real hot, so I don't think it raises cabin temperature to any great degree in the summer. The compressor noise is only barely audible. Two things that I have had to deal with though, are that dust is sucked in through the exterior vent, and ends up on my countertop a bit since air is drawn from the outside to the inside. And second on one trip flies found their way into the cabin via the two vents which was quite annoying. I placed some filter material in the exterior vent to address that problem, so no issue now.
Just thought I'd give you another perspective. Take a look at the photos and see what you think.
Poky
I installed an Isotherm 130 L in my rig, and when I looked at the manual, it suggested an outside vent, and a path across the compressor, then venting to the inside. Keep in mind this might be more for a marine application. But that's how I configured mine. Below are some photos from my build that show how I cut the vent holes. I know FWC uses the same two exterior vents on the 2 way compressor fridge that are also used on the 3 way, but not sure why, there's nothing at the bottom of the two way fridge. Maybe it's just to let a large volume of air in behind the back of the fridge. I have those vent covers if I ever decide to take the same direction.
Anyhow, my arrangement seems to work fine, and you can feel warm air from the compressor come through to the inside of the cabin. It's not real hot, so I don't think it raises cabin temperature to any great degree in the summer. The compressor noise is only barely audible. Two things that I have had to deal with though, are that dust is sucked in through the exterior vent, and ends up on my countertop a bit since air is drawn from the outside to the inside. And second on one trip flies found their way into the cabin via the two vents which was quite annoying. I placed some filter material in the exterior vent to address that problem, so no issue now.
Just thought I'd give you another perspective. Take a look at the photos and see what you think.
Poky
I've done two 130L Truckfridge installs on my camper builds. Both were vented with a source of fresh air outside and a vent inside AND an additional fan to suck air into the inside. Just finishing the 2nd build now. Here are some pics:
This is the fridge location. Note the small 4" opening. Since the fan on the fridge is only a 4", and the condenser coils are not huge, I'm not sure I see the point in a huge outside vent opening
This is a closeup of the vent opening with screening installed to keep the critters out
The original fan has directional markings on it. The air flow is so slight from this fan, it is hard to tell which way it is going. It sucks cold outside air INTO the compressor.
I bought this fan because it was a 4" squirrel cage style vs using any on the myriad of computer fans I have lying around because their is no room to vent it on the side like I did in my Hawk build. Instead, the squirrel fan sucks hot air from the compressor and blows it into the camper.
While it did move a huge amount of air, it was extremely loud!
Found a fan designed for use in home theatre systems. Super quiet, but nowhere near the air flow. Still way more flow than the stock fan though. This fan is designed to plug into a usb port (5v) instead of 12v. I added a cheap adapter, and am happy with the amount of air and the near silent operation. It is quieter than the original.
I did experiment to see if it would run on 12v, and it does, and blows a lot of air. Too loud though.
These are the wires I tapped into. They supply the original fan, and if the load of your additional fan is low enough (sub .5A) then it will work. More than that, and a protection circuit trips shutting the fridge down. If you still want to use a fan that draws more juice, you will need to add a relay. The advantage of using the existing wiring is that you don't need to add an external switch, and the added fan runs only when the compressor is running.
This is the fridge location. Note the small 4" opening. Since the fan on the fridge is only a 4", and the condenser coils are not huge, I'm not sure I see the point in a huge outside vent opening
This is a closeup of the vent opening with screening installed to keep the critters out
The original fan has directional markings on it. The air flow is so slight from this fan, it is hard to tell which way it is going. It sucks cold outside air INTO the compressor.
I bought this fan because it was a 4" squirrel cage style vs using any on the myriad of computer fans I have lying around because their is no room to vent it on the side like I did in my Hawk build. Instead, the squirrel fan sucks hot air from the compressor and blows it into the camper.
While it did move a huge amount of air, it was extremely loud!
Found a fan designed for use in home theatre systems. Super quiet, but nowhere near the air flow. Still way more flow than the stock fan though. This fan is designed to plug into a usb port (5v) instead of 12v. I added a cheap adapter, and am happy with the amount of air and the near silent operation. It is quieter than the original.
I did experiment to see if it would run on 12v, and it does, and blows a lot of air. Too loud though.
These are the wires I tapped into. They supply the original fan, and if the load of your additional fan is low enough (sub .5A) then it will work. More than that, and a protection circuit trips shutting the fridge down. If you still want to use a fan that draws more juice, you will need to add a relay. The advantage of using the existing wiring is that you don't need to add an external switch, and the added fan runs only when the compressor is running.
The whole idea is to keep the air around the refrigerator condenser (the heat exchanger outside the fridge) as cool as possible. This makes the refrigerator as efficient as possible. What the manufacturer specs is usually the minimum ventilation required. Adding more ventilation, better positioned ventilation, and/or forced ventilation can maximize efficiency.
I completely separated the ventilated condenser box from the interior of my camper to eliminate insect/dirt infiltration into the living space.
I completely separated the ventilated condenser box from the interior of my camper to eliminate insect/dirt infiltration into the living space.
craig333
Riley's Human
Before I vented mine I noticed the countertop above the fridge got noticeably warm. Not anymore. I wish I had room add an interior vent. Would be nice to vent inside in the winter and outside in the summer.
One last thought...would some type of insulation on each side of the frig help with keeping the frig a tad cooler in the summer months. I may have any inch or two on each side to play with and plenty of room on top as I had to take out a small drawer to make the 85 work. I thought the insulation would help with keeping the frig a little more secure on some of those bumpy back roads. I've hear that they make some thin insulation for tight spots, but haven't had any luck finding the right stuff. thx Tim
billharr
Senior Member
I wrapped mine in R-13. Back is open, fan (now 2) in top vent, I pull air under the fridge to cool coils.TahoeT said:
I used rigid pink Foamular and isopoly around my fridge. ~ 2.5" top, bottom, and sides; can't do anything insulating in the back (full length condenser). Added 1/4" foam to the door. Seems to help (impression, no good data).TahoeT said:
I made it as tight a fit as I could.
Sorry for the bad picture; you can kind of see it in pic#2. Camper is currently under a tarp so I can't get a better one.
https://www.wanderthewest.com/forum/topic/9972-renovating-sköldpaddan-–-1977-grandby-interior-build/?p=114561
jim
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