Furnace output, or how to make one more efficient

[Darrell T]

As mentioned above I am wondering how to make my PUPs furnace more efficient.
I have a clean flame, plenty or airflow into the cabin and very hot exhaust.
I used an infrared temp gun to check the temp of the heat exchanger. The front of the exchanger right near the cabin air outlet is over 240 deg F while the air temp is a mild 115. The heat at the back of the heat exchanger, the end nearest where the heat exchanger exits the heat chamber where the cabin air picks up the heat is even hotter.
Has any one attempted to put some sort of heat sink fins on an existing heat exchanger running in line with the natural airflow thru the heater?
Has any body actually measured the heat they are getting out of the front of their heater?
Thanks
Darrell

[tlhdoc]

I haven't heard of anyone moding their furnace.  Good luck and keep us updated on any thing you try.

[PattieAM]

My Niagara's furnace is located towards the rear of my camper, and, if I leave the door off my bathroom, the potty is the hottest seat in the camper!

I am having a neighbor who works with sheet metal, etc., make me a magnetic flow director as the rear of the camper seems to get warmer than the front.

I haven't done any official testing, but watched my indoor therm. raise 12 degrees in all of 5 minutes of running the furnace while enjoying camp driveway!

['tiredTeacher]

I am having a neighbor who works with sheet metal, etc., make me a magnetic flow director ...

Make a ... ah, say what?

[flyfisherman]

To help with better heat distribution (and also with condensation when necessary), I use a small 12V automotive oscilating fan that I clamp onto the sink counter top and it sweeps that ceiling air fore to aft. It do make a difference.



Fly

[beacher]

....I am having a neighbor who works with sheet metal, etc., make me a magnetic flow director as the rear of the camper seems to get warmer than the front....

You do know that there is an actual deflector part made by Suburban for this purpose.  Your dealer should be able to get one, or you can call Suburban.




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['tiredTeacher]

You do know that there is an actual deflector part made by Suburban for this purpose.  Your dealer should be able to get one, or you can call Suburban.QUOTE]

Oh, I get it! A magnetic, flow director. Not a magnetic flow director.  :eyecrazy: (I didn't think that Suburbans put out a magnetic flow.) :sombraro:

[Jon Spencer]

um, sorry to hijack, but I don't have a furnace. Even so, me and mine had a wonderfully warm nights sleep with some good sleeping bags out at Casitas last weekend and it dropped below 40 degrees.  Had an electric heater, but it pooped out from the night before.  It didn't heat worth a damn anyway.  What's the best way to heat a PU aftermarket?  Again, sorry for the hijack.

[austinado16]

There have been a bunch of threads on heaters.....Mr. Buddy, Catalytic heaters, ceramic electrics, etc.  Search the forums and you'll find them.

Ours didn't come with a furnace, so I found an original one on ebay, and installed it in the factory location (which was a low cabinet area in the right rear corner.  Works great and looks OE.

[flyfisherman]

um, sorry to hijack, but I don't have a furnace. Even so, me and mine had a wonderfully warm nights sleep with some good sleeping bags out at Casitas last weekend and it dropped below 40 degrees.  Had an electric heater, but it pooped out from the night before.  It didn't heat worth a damn anyway.  What's the best way to heat a PU aftermarket?  Again, sorry for the hijack.

My Starcraft did not come with a "furnance" either, which is O.K. because I did'nt want another one anyway. For me and for what I do, they make too much racket!

I've been using the Mr.Buddy L/P Heater now since I first discovered the heaters at Lowe's Bldg. Suppy, the fall of '00 as best I can recall. I should say that I try not to be camping out in extreme weather, although we have been caught out a few times in the early spring or late fall when temps did drop below freezing; lowest maybe about 25 degrees. With my 8' box Starcraft Mr.Buddy has kept things liveable even at freezing, but I think that is about it's comfortablity limits (and that's with the bunk ends covered with Reflectix insulation sheets).

However, when camping where there is electrical hook-ups, I do use a Pelonis ceramic heater and it manages to do an adequate job of keeping the camper once again liveable. The Mr.Buddy heater will out perform the little ceramic heater, but why pay for propane when your buying the electric with that type of site?

One other point with the Mr.Buddy heater. I always make sure of a couple things when using the device: (1) ~ Making sure there's ventilation for the oxygen demand, and (2), which should be #1, be mighty careful about fire ... where the heater is placed when in operation. Popups will burn to the ground mighty fast.




Fly

[ScouterMom]

I have a 'mr buddy', too - bought it to work in the garage, but took it camping and it works great!

However, you might want to consider getting a CO2 detector (just in case).

My camper came with a furnace, but it was old and the propane tanks weren't set up right so we didn't use it last season.  haven't tested it yet.  I never thought about the noise of a furnace - but a couple of people have mentioned it, so it might be an issue.  the Mr. Buddy is very quiet, and has the added 'warm glow' of almost having a little fireplace inside!  I usually put it up on a counter top, rather than on the floor, so that the dog's fluffy tail stays away from it and the heat is at bed level.

I have also used small electric heaters in the past for the same reasons given above.  They pull electricity like crazy, so I don't use them at home, but if you've paid for an electric site, it's all the same, and no flame or CO2 to worry about.  

If you camp at electric sites, you might think about getting an electric mattress pad.  You can get them for regular beds at any Dept store (K-mart, target, etc) and they will keep you toasty warm, out to the edges of the bunks, at night. We've even used them tent camping on an AIR MATTRESS in the late fall - worked great.  I've never had any heater that could keep the far corners of a PUP bunk warm in the wee hours of the morning.

STay warm!

laura

[Darrell T]

I appreciate all of the input but the idea is to make the heat transfer from the burner assembly into the heat exchanger more efficient.
I have propane heaters and a sleeping bag rated to 20 below zero so that isn't the issue.
I don't mind sleeping in a tent when it's zero outside.
I like to tinker with things and make them better. This is just another project to see if I can make it better.
DT

[austinado16]

I think by "existing design" they can only be so efficient.  Something to do with how the are exhausting hot air that can't be used for direct heat, and isn't used as a heat source.

One thing I did with mine was lined the insides of the cabinet area it's in with a couple layers of Reflectix Insulation, and woven ceramic insulation (like you'd put inside the walls of a pottery kiln).  My goal was to keep the furnace from radiating it's heat into the cabinet wood, and refrigerator which is just on the other side of a thin wood panel.  I'm hoping that keeping all the heat "in" the furnace area will produce hotter air out front of the furnace.

Then again.....I could just be smoking crack.