Anyone on here have/use a propane-fired On-demand water heater? I'm trying to get a bead on how much fuel they burn for a given amount of use. Say for one shower a day & a load of hand-washed dishes every couple of days? How long will a 40# bottle last me?
The one in my house burns less then 300 gal a year I take a shower for at least 15 to 20 minutes on average plus my wife takes a bath at night and a shower in the morning. plus the heater goes to propane when it gets about 35 degrees outside. I don't know about the camper ones mine is a noritz or something like that.We live in Maryland but it isn't so merry.
07 Ram 3500 Quad cab DRW Cummins 6.7,6 speed auto, Larime 4x4 long bed (affectionatly known as "Super-awesome-mega-truck")11/17/12
05 Kubota RTV 900.
04 Club Car Precident
2013 fuzion 322 all the bells and whistles.8/25/2012
2000 Yellow Lab mix Dog , Earl
one lb of propane is about 22000 btu's.
it takes 8.34 btu's to heat one gallon of water 1 degree (F).
ASSUMING a 50 degree rise (70 to 120), that is 417 btu's per gallon,
30 gallon shower, 1 gallon dishes, that is 12900 btu's a day.
40 lb tank 80% full is 32lbs, 704,000 btu's.
just under 54 days. This assumes 100% efficency, I would plan on closer to 45 days.
Take longer showers, use the stove / range, wash your hands, etc and you will burn it faster.
An RV approved on demand water heater will use slightly less propane per gallon of hot water than a tank tyoe water heater because the on demand type doesn't have to burn extra propane to keep a tank full of water hot. The actual propane will depend entirely on how much hot water is used. If you can limit showers, etc. to the same amount of usage you can get from a tank type water heater, you will use less propane. Use more hot water, propane consumption will go up. Also, keep in mind an on demand water heater runs on propane only whereas many tank type water heaters can run on propane only, electricity only, or both at the same time.
Whether an on demand water heater will be practical or not depends on many factors, such as whether you will be on full hook ups or boondocking, how much hot water you need (or want) at any given time, and the cost of electricity vs. propane.
Atwood has some new on-demand propane water heaters which take up a 6 gallon opening that have been getting some good press.
Last I heard, the release of the Atwood tankless water heaters has been delayed due to a parts issue but I agree that they look promising. The press releases and Atwood's website haven't been as informative as I would have liked but, after exchanging several e-mails with Atwood, it appears their new tankless water heaters will be comparable to the Precision Temp RV500 and the new RV550 (which, last time I checked, also hadn't been released yet). Atwood teamed up with Precision Temp, which has been around for years, to design the new water heaters. The biggest differences are the Atwoods are more compact (the RV500 requires a hole sized for a 10 gl tank type heater) and somewhat less expensive than the RV500 (the RV550 is in a league of it's own since it vents through the floor, allowing it to be installed anywhere in an RV, not just on an outside wall) although, when one looks inside both, the components seem to be similar, if not the same. One thing Atwood's website and press releases haven't been saying is the difference between the 45,000 BTU model and the 50,000 BTU model. Besides the obvious 5k BTU difference, the 50k model also has cold weather protection.
The Gerards also use similar components to the Atwoods and the Precision Temps but have less sophisticated gas controls. This cuts the price considerably but it results in an unintuitive operating procedure that often causes user grief if they are unaware of the difference or until they adjust to it. While the Gerard does put out plenty of hot water in most situations (I've actually seen one in operation), I would prefer the better design and construction of the Atwoods and the Precision Temps; they don't cost that much more than the Gerard, especially the Atwoods.
To some extent a typical RV water heater is already "on demand" ;-)
The on demand part refers to the water not being heated until there is a demand for it. other terms are tankless water heaters and instant water heaters.
Well to that extent that is what the electric and gas switches are for for my regualr water heater...
Thats my solution also since I don't ddo a lot of cold weather camping. We turn them on a few minutes prior to needing hot water and then off once we are done. When we sit down to eat, they go on and are ready by the time we need them for dishes. Turn them on 15-20 minutes lead time for a shower and we are good. Saves me a little propane during the course of the day but it's not the end of the earth if we forget to turn it off when not going to be used for a while. My experience is that the water heater and fridge uses very little propane, the furnace is the only real propane hog.
2011 Silverado Crewcab 4x4
2012 Passport 238ML
Hope your travels are safe and the friendships made camping are lasting.