Window AC installed above fridge. Too much heat?

[huasnaian]

Hey all!

I have an older lance squire 3000 that has a swamp cooler on the roof. I am looking at installing a window AC (fridgeaire 5000btu) in a space above the propane fridge and share the fridge venting area with the a/c. Should I be worried about the heat released from the back of the fridge affecting the a/c's performance?

My doemetic fridge died and I have installed a small fridge I found at a garage sale. Can't find a brand on the new fridge but it keeps cool, unless its over 90F. I have seen the mods to add a 12v computer fan to help dissipate heat and wonder if the extra heat from the a/c would not help this matter. On the other hand, if I was running the a/c then the fridge door would be open to allow the power cord to reach the generator, increasing the air flow. I would like to utilize the extra space above this fridge since I would not have to cut a hole for the a/c and not lose my view from the back window.

I am going the window ac route because I can source the ac and generator for under $300, which is less than a roof ac alone.

Any advice is appreciated.

[DWeikert]

I think your biggest problem is getting sufficient airflow for this to work. Just putting it in the air column the fridge uses won't allow enough fresh air to pass through the heat exchanger. Feel the airflow on the outside of a window unit when it's operating. Unless you allow for that much fresh airflow, it's going to be a disappointment regarding cooling ability.

[jaycocreek]

While some have not had the luck of a 5K unit doing it's job, you will find brands do make a difference.Some brands just do not blow cold air and some do, just like some auto AC's blow super cold air and others not so much.

Mine is a Perfect Aire® 5,000 BTU Window AC/Model Number: 3PNC5000 and it blows really cold air not just semi cold.Bought at my local Ace store originally for my 30ft trailer in the bedroom, in which it did a great job.

Draw is 4.8 amps max, so my Honda 2K really likes it without the loud surges.

As to the opp and the question,I would not do it that way as it does throw alot of hot air out the back of the AC unit.They are so light I see no need to permanently mount mine and I only take it as needed.The 10" O2 fans do a bang up job into the lower 80's in keeping a person cooled down.Above 80-85 I throw in the AC but it does really cool down in the hills around here at night.I have seen 95 in the day and 30's at night.That makes a difference in AC needs.

[mkirsch]

I assume you plan on setting this AC unit on top of the refrigerator with the back of the AC unit essentially flush with the side wall?

A standard window unit will not work well like this, if at all. As someone mentioned earlier, window AC units pull air in around the sides and blow it out the back. They need clear open access around the sides to pull in cool air and blow it through the coils.

Even if you leave air space around the sides of the unit, it still won't work well/at all because it is pulling the hot air it just exhausted through the coils right back in. In open air this still happens, but to a drastically smaller degree. When you enclose it the hot air is ducted right back into the unit.

What you are proposing would be best suited to a "sleeve unit" type of air conditioner. Unfortunately you won't be able to buy one of these for $79 at Walmart.

[kohldad]

I put a new 13.5 Carrier Roof mount in my old Lance and it was so noisy and cycled all the time.I would never put a 13.5 back in a pickup camper.

That is the size on my 8' camper and it is about twice what I need. Each day, I actually open a couple of windows to make it run more so the moisture is actually pulled out of the stuff. If I don't, everything starts getting damp because of the short cycles. Luckily, I don't camp that often in the hot summer, and have found the trick to make it bearable, just hate wasting the electricity.

While the 5k may not bring the temp down to 70* in the camper during the day when the sun is shining on it, it will definitely make it bearable, especially at night when you are trying to sleep.

[jaycocreek]

I have a 5000 BTU window A/C that I bring along to the desert as an emergency spare.
I’ve tried it out, mounted in the dinette window, and it’s woefully inadequate.
I guess that’s why campers come with 9000 or more BTU A/Cs.

That's interesting!.I have a 5K BTU window unit that I put in my Lance 9.6 when it was hot out and I was working inside..It kept it right around 70 degree's with it 95 outside.I put it in the dinette window with a slight tilt for water drainage. It worked so well,I scrapped the idea of a noisy roof mount.

The 5K window unit is super quiet and my Honda generator just purrs along running it.It is really light to move around and does the job perfectly.I often wonder why they don't use them instead of the big noisy ones.

I put a new 13.5 Carrier Roof mount in my old Lance and it was so noisy and cycled all the time.I would never put a 13.5 back in a pickup camper.

[huasnaian]

burningman wrote:
I have a 5000 BTU window A/C that I bring along to the desert as an emergency spare.
I’ve tried it out, mounted in the dinette window, and it’s woefully inadequate.
I guess that’s why campers come with 9000 or more BTU A/Cs.

I think I you’re making this way too difficult and screwy. I think you could scrounge up a used roof A/C for cheap. A few months ago I scrapped an old camper that had one, I literally threw it away..
Those A/Cs often outlast the camper they’re bolted to.

Space is always at a premium, why give up a cabinet?

I appreciate your input but I'm disappointed. I only really need ac when the temps are above 90f and sometimes reaching above 100f where I like to summer camp. My old turbokool swap cooler works great in my dry climate up to 90. My lance only has 1 roof vent in the kitchen/dinette area, in addition to the bath and escape hatch. I don't want to remove my swamp cooler for something I will not use every day.

My friend has a roof mounted ac on his mid 90s lance and his 2000w peak genny can not start it most of the time. He is now looking at a larger generator. I was hoping a small ac and a small lighter weight generator would keep my 8ft camper cool the few times I need it. Guess I need to re-think my plan.

[burningman]

I have a 5000 BTU window A/C that I bring along to the desert as an emergency spare.
I’ve tried it out, mounted in the dinette window, and it’s woefully inadequate.
I guess that’s why campers come with 9000 or more BTU A/Cs.

I think I you’re making this way too difficult and screwy. I think you could scrounge up a used roof A/C for cheap. A few months ago I scrapped an old camper that had one, I literally threw it away..
Those A/Cs often outlast the camper they’re bolted to.

Space is always at a premium, why give up a cabinet?

[kohldad]

All a/c drain based on the amount of moisture in the air. Even the small ones will drain almost constantly on a high humidity day.

Sealing to the camper as you mention seems fine. Just make sure you tilt the unit back a couple of degrees to make sure there is always a good tilt to the back.

Now, the only way to make sure the a/c had enough cool air to function, would be to put a box the same size as the unit so all the air coming out the back of the unit doesn't mix with the air being pulled into the sides of the unit. Seal this box to the vent. Then the air being pulled into the outside side vents should be pulled from the outside through the vent. There should be enough outside draft or simple air rising to minimize the air mixture outside the unit, at least to a minimum.

Or, you could use fans to make sure the air is coming in through the vent, but you would need at least two or three 100 cfm fans to move enough air. Would be easier to and more reliable to just add the box imo.

[huasnaian]

kohldad wrote:
The fridge won't interfere with the a/c, but the a/c will interfere with the fridge.

One thing to remember is the a/c unit will both pull air into the sides and exhaust out the back. These need to be separated from the two. Same with the front. With the a/c unit enclosed in the camper, the exhaust will get pulled into the intake and keep it from working quickly. There won't be enough ventilation to keep the air cool.

What you could do is set the a/c on the roof and then make an enclosure to handle the inside air, part for coming into the a/c and part for the exhaust. Exterior air won't be a problem since the unit is outside.

Don't forget, you also have to worry about the water dripping from the unit. Sitting on the roof, this can just drip on the roof and run off the side of the camper. If you put the a/c above the fridge, how are you going to ensure the water is properly drained?

Another

Thanks for the reply kohldad,

I guess I should have been more specific in my original post. When I installed the smaller fridge I framed out a back wall above the fridge and insulated with rigid foam so the heat released from the fridge would not enter the interior of the camper and go up and out the original fridge roof vent. Then I installed a piece of plywood that covers the top of the fridge and have used the space as a pantry for dry goods.

I was thinking of removing the wall I built and placing a plastic pan with drain hose on top of the fridge that the ac would sit in. Then frame around the ac unit in the same spot where a window would seal around the unit which would create an air barrier from the interior of the camper and the airspace behind the fridge the vents to the roof.

Do you think there would be adequate ventilation and fresh air if I added a fan behind the fridge that would pull fresh air in and blow ac and fridge heat/exhaust towards the roof vent


From what I have read the smaller units don't drain constantly. Can anyone confirm? I am still in the planning stages. I need to buy the ac unit and run it in my house to see. Problem is we are not having hot weather that replicates summer.

[kohldad]

The fridge won't interfere with the a/c, but the a/c will interfere with the fridge.

One thing to remember is the a/c unit will both pull air into the sides and exhaust out the back. These need to be separated from the two. Same with the front. With the a/c unit enclosed in the camper, the exhaust will get pulled into the intake and keep it from working quickly. There won't be enough ventilation to keep the air cool.

What you could do is set the a/c on the roof and then make an enclosure to handle the inside air, part for coming into the a/c and part for the exhaust. Exterior air won't be a problem since the unit is outside.

Don't forget, you also have to worry about the water dripping from the unit. Sitting on the roof, this can just drip on the roof and run off the side of the camper. If you put the a/c above the fridge, how are you going to ensure the water is properly drained?

Another