LynnandCarol wrote:
We have six gallon. I always have enough for my shower. May need 10 or 15 min to be ready for next shower.
That might work fine in Texas with 65F water coming out of the ground. In Portland Oregon, the ground water is a chilly 45 in the winter and 55 in the summer.
What I did to increase my shower time is fill the fresh water tank with warm water. By using a tankless water heater, I can fill it with about 80 - 85F water, then take a refreshing 15 minute long shower at 110F!
However I agree, that when it is 45F into the RV, the 6 gallon water heater on gas only runs out quickly! So that was my solution.
I bought a L5 water heater at Amazon.com for about $129. Shipping was a nominal extra fee. The slightly larger L10 water heater will heat 10 liters per minute, not the 5 liters of the L5, so it takes me a little longer to fill the tank with hot water. The L5 is about 37,000 Btu's, while the L10 is about 55,000 Btu's. Your 12 gallon heater is probably in the 10,000 to 12,000 Btu range, while typical 10 gallon is around 10,000 Btu's and my 6 gallon is 8,800 Btu's per hour.
So the tankless has them all beat for warming the water quickly, however the tankless can only supply a small amount of water per minute at that temperature rise, while the tank water heater is drawing from it's reserve of hot water the whole time it is warming the incoming 45 - 55F water to 105 for your shower.
So pre-heat your fresh water tank if you can! It will offer the longest showers for a reasonable cost.
You can buy a tankless RV water heater, that fits in the same space as a 10 gallon water heater takes up. However they lack the controls that a house tankless water heater has, and because you sometimes are on a pump, the changing water pressures make it difficult to get a warm shower without scalding that is surely followed by the tankless heater reaching it's overheat limit and shutting off - so 55F shower water for a few seconds too!
Fred.
