Furnace/water heater exhaust harvest?

[JasonVideo]

While camping in the "cold" last week (got down to 15 degrees) I wondered if there's any kind of aftermarket add-on to harvest the warm exhaust and use it to warm the tanks or undercarriage or anything? Seems like a waste of energy.

Thanks,

Jason

[Crabman]

I really don`t think you want that blowing under your trailer, the carbon monoxide possibly entering the trailer would be a concern.

[Grumpy]

No, besides you would end up with carbon monoxide being in an area where it could migrate into the coach.

[Paulx213]

You wouldn't want to use the exhaust directly for the reasons already mentioned. No reason you couldn't build a heat exchanger though. If the exhaust were to blow through a small radiator that had a coolant circulating through it you could definitely use that heat safely.

Haven't seen one on the market but it sounds like an interesting project if you camp in cold weather enough. The heaters they use in trailers aren't very efficient and it would a step in the right direction to reuse the waste heat.

[Seann45]

Not only is there a CO danger there would also be a danger of fire from the heat where it is NOT supposed to be.

[SmokerBill]

Just switch to using a Mr. Heater Big Buddy instead of the furnace. 100% efficiency, minus the small amount you lose from having a couple of windows cracked open. My Big Buddy uses much less propane than the furnace, and there's no draw on the battery bank.

[JasonVideo]

We stayed for 7 nights in NC last week. Lowest temp was 15. Used the furnace and an electric heater sometimes. Also used propane for cooking and hot water sometimes. Used 10 gallons of LP. Not bad I think. Could have done better if we'd tried. I think that's pretty good. Is that about right? Not looking to add more heat, just use the exhaust to gain some efficiency. Just an idea.

[RedHorse1]

I expect our water heater/furnace are similar in operation. Adding a heat exchanger to the exhaust on the water heater might prove a bit tricky since the burner isn't forced air. Not sure about the furnace but I'd expect it's the same. A heat exchanger would probably add some flow restriction and at least would change the combustion characteristics. Might be able to tune the flame tho.

[TX_Arvee]

I dont think I would attempt this.