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I installed one of these Cheep heat systems in our Fiver 4 or 5 years ago and totally love it. It does a fantastic job as long as you are plugged into a 50amp service. I installed a couple switches so that it will run on a 30amp service but it will not produce as much heat as the 50amp does. Will give it a 5 star rating!

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When campgrounds do start metering AC, they are going to mark it up. I think 11 cents from an RV park is a pipe dream.

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Most states do not allow campgrounds to mark up the cost of their electric power. And base costs per kWh vary wildly by state and region of the country. That’s why I need to create an interactive spreadsheet to calculate and compare actual propane vs electricity costs.

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I just left an RV park where my electric was metered. They charged 8 cents and no markup.

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That’s a great price. How many kWh did you use?

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Jan 7·edited Jan 7

We were at the metered site for 44 days and used 2848 kwh or 64.7 kwh/day.

For reference we have a Jayco 377RLBH 5th wheel trailer. Last year, I installed the RV Comfort Systems 50 amp add-on unit. I never used propane for heat. Our heat was provided primarily by the living room fireplace and a roof top AC unit with heat pump until the temp got down to the low 40s. Below approximately 42 degrees, I switched over to the furnace while continuing to use the fireplace. I maintained a temp of 72 degrees when the heat was turned on. I don't recall ever needing the AC since the temps never got above the low 70s. When the temp dropped into the mid to upper 20s, which it did a few times, I used several small (400 watt) space heaters because the Comfort Systems unit couldn't quite keep up at continuous sub-freezing temps. Also, our water heater was set for electric, not propane. It's a 10-gallon unit.

For reference, we stayed in Wichita Falls TX from just before Thanksgiving until shortly after the New Year. Typical daytime temps ranged from the upper 40s to low 70s. Night time temps ranged from the upper 20s to low 40s. If you wanted to look up the historical/actual temperature ranges, they are probably available online.

I kept daily usage records in a spreadsheet, if you are interested.

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Did you provide the spreadsheet for the comparisons? I watched the live feed but didn't hear anything about it.

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My Atwood furnace specs at 76% efficiency per the label on the furnace which shows input and output BTU.

I have always used a nice round multiplier of 18 as it's close enough.

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We have a 2003 Foretravel U320 which is a high end diesel pusher.

Our heat choices as built are 2 heat pumps in our roof top air cons, which we use when temperatures are above 42 degrees but cold enough to heat the coach. And we have a Aquahot diesel burner which also has one electric element in it.

The Aquahot provides hot water and also circulates through radiators inside (and in water bay) with 12 volt blower fans to distribute the heat.

We also have 2 ceramic electric heaters which we use when temps are too low for the heat pumps, and this reduces our diesel burn in the Aquahot. We never use the electric heaters in high mode (1500 watts each), but only low (appprox 750 watts each). This reduces the risk of pulling so many amps from the outlets, coach wiring, and heater wiring.

This combination gives us options. Where we are now electric with taxes and fees is just over .17 per KW. My last tank of diesel was $3.94 per gallon.

The Aquahot burner uses .41 gallon diesel per hour of constant run time (an of course it does not run all the time, and very rarely would it run an entire hour).

Electric element in the Aquhot is 1650 watts, and probably runs many hours in cold weather (it maintains temps slightly higher than the diesel burner is set for). The diesel burn can provide 65,000 BTUs.

The Aquaot website says AVG diesel Fuel Usage /Day Dry Camping 1-4 Gallons, AVG Fuel Usage/Day Shore Power 1-2 Gallons.

I have no idea which is more price efficient, electric at .17 per KW versus diesel burn at $3.94 per gallon. But we are stationary for the winter months, and are using electric (which we pay for) over diesel when we can get enough heat from it, just to not have to move to refuel until late spring travel months. Probably using 50 - 60% electric heating and the rest diesel burn on colder days.

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And our Nov 26 to Dec 26 electric bill was $160.

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As mentioned, the resistance-based electric heat is 100% efficient.

Also note that gas furnaces can be designed to be much better than 60% efficient, with some modern home gas furnaces up to 98.5% efficient.

Compare that with an RV heat pump with up to 400% efficiency.

A concept proposal for RV'ing HVAC systems: an RV-sized hybrid heat pump dual fuel gas/electric. ... programmable to incorporate cost and availability of LP and electricity.

And while dreaming of a RV hybrid HVAC system, incorporate water heating, and combining elements of water heating into a holistic energy and cost-efficient design. How efficient are RV's in heating the water, and/or keeping it from freezing?

Although I might miss, on cold mornings like today, the warmth of the furnace and tankless water heater exhaust blowing out the side of my RV.

How many heat exchanger units do we really need in an RV? Can any be combined economically? Air conditioner, furnace, water heater, generator ...

not counting the multiple radiators/heat exchangers in the engine compartment.

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Every RV propane furnace I’ve looked at is around 60% efficient, nowhere near the 98.5% of a residential furnace. And I’m not sure of your 400% heat pump efficiency rating for an RV heat pump. My casual studies show closer to 200% efficiency. But please provide any references you have on those efficiency ratings for RV furnaces and heat pumps.

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My 25-year-old home residential furnace (natural gas) is also rated around 60% efficient. However, natural gas is relatively cheap here, and it is many times cheaper to continue using it rather than upgrade to a residential electric air-based heat pump.

I, too, am not aware of a 98.5% efficient RV furnace, but just checking my RV's Atwood 30,000BTU furnace with a FLIR shows that much of it's heat is going out the exhaust, and have to believe they can be much more efficient. As far as I know, RV furnace manufacturers don't publish efficiency ratings, and the published peak fuel consumption incorporates assumptions. My LP tank doesn't have the equivalent of a Victron shunt to accurately measure fuel flow.

Calculating, though: 1 cubic foot of LP produces 2516 BTU.

My Atwood 30,000BTU furnace manual claims it burns, at peak, between 12 and 13 cu ft of LP/hr (30.1kBTU to 32.7kBTU), well over 80% efficiency. But I am highly skeptical: missing from that calculation is critical assumptions like cycle time.

An archived article at RV.com states "All RV furnaces are AGA (American Gas Association) certified to be 80 percent efficient, but testing by RV Comfort Systems technicians reveals that that figure may be a little optimistic."

(Source: https://www.rv.com/archive/rv-comfort-systems-electric-element-can-lower-heating-costs/ )

As for RV heat pumps:

Assuming efficiency is simply defined as heating energy/electrical consumption, rather than the thermodynamic equation e=1/1-(TC/TH):

The Houghton Belaire A3800 (sold by RecPro) is rated at 15000 BTU/Hr (roughly 4.4kW), with an input power consumption rating of 1300 watts…an energy efficiency of over 330%.

To compare that with automotive industry heat pumps, the Tesla Model 3 heat pump is considered to be about 300%.

Advertised as to be released in North America in the summer of 2024, the Eberspächer Breezonic 3800, with an inverter-driven compressor, has a heat output rating of 3.2kW; however I am not yet aware of the Breezonic’s input power other than it can be operated off of a 2.4kW generator.

Sources:

pg 25 at https://www.houghtonleisure.com/files/V0-7340-2000-01(Combined%20Ducted%20and%20Non-Ducted%20Unit)-small.pdf

https://www.eberspaecher.com/en/press/press-releases/individual-view/eberspaecher-breezonic-powerful-air-conditioning-system-with-heat-pump

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Why do they include the startup and shut down run times of the furnace with no flame against the propane efficiency? If there is no flame, no propane is being used, no wasted money "at the register" as they say.

How many trailers have heated underbellys? The Rockwood MiniLites your familiar with don't. Not sure but I'd guess your GeoPro doesn't. My Flagstaff SuperLite has floor vents so I expect some heat lose due to typical poor trailer construction but not truly heated.

At $1000+ and time/money to install I'd opt for installing a proper 20A receptacle and using a $40 heater.

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Oops- Connected not control Ted . Gotta love auto fill.

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Cool find but I have some issues with it. 1. You are going to have to run 120V to it and for 2 of the 3 models you will need 2 hots (one from each leg) Good ole atwood and Suburban RV furnaces run on 12v. There are a few other options. I have a Truma Combi in my rig. RUns on Propane and or electric and also makes hot water. I have a heat pump AC unit. They also have for years made heat strips for AC unit which already has 120v available.

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Besides Rv comfort sys no shut off when cold, why would I want their system vs my heat pump that sends heat thru ducts? Know might be cheaper but not sure how long we'll krrp our rv. We also only camp warm season and stire rv indoors at 45 degrees and plugged inti 120 electric. We use heat pump control Ted to ac except at night when too noisy so use propane. Wonder cost of product and installation?

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Jan 5·edited Jan 5Author

If you already have a modern heat pump in your RV then there’s no need for a Cheap Heat system.

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Under 40 degrees ambient heat pumps are not fully usefull. Cheap heat would still be working below freezing.

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True that!

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