Girard tankless water heater not so good for boondocking?


New member
I’m trying to decide between a traditional 6 gallon Atwood and a Girard tankless water heater for our Avion truck camper re-build. We expect to mostly be boondocking. While I like the tech, lower weight, and less propane use of the Girard it looks like it will result in more water use which could be an issue with our small holding tanks. Does anyone have experience to share with a Girard units in boondocking situations?


Engineer In Residence
If you are concerned about water usage, you could rig up a timed bypass valve. This would be plumbed to dump water back into the holding tank for say, 20 seconds? That would give the tankless time to get up to temp. You would need to select a valve and plumbing that results in flow above the minimum required for the heater. 1GPM or so? 12V 3/8 valves are available, and an adjustable timer board is 10$ or so. That would allow you to hit a momentary switch to preheat.
Or a much more simple plan is to have vessel to catch the first water in to use for other purposes. We use the dog water bowl at the sink because the bowl is clipped to the floor right under the sink, and the coffee pot in the shower because it is close to the stove.
Conserving water has turned into a science after all the years we've spent "mi compo" down in Baja.


Renaissance Redneck
I have installed multiple units of the tankless heaters. The Girard gets poor reviews in comparison to the Suburban/Nautilus. I wouldn’t use one for boondocking personally. It’s not just the water used getting up to temps, it’s the fact that you don’t run out of hot water until you actually run out of water! If you are very disciplined, you might be ok, but if you are not paying attention, that quick shower can drain your fresh tank in a couple of minutes. For a truck camper, I’d go with the 6 gallon Atwood.

Bayou Boy

I see comments on various RV groups all the time about people buying new campers and going back to tank water heaters after having tankless all the time. That's enough for me to keep the tank heater in my ORV.


New member
Thanks for all the input on this, I knew this was the right place to ask about this. I like the tech solutions with timer or temp diverted valves, and a good lead on the Suburban Natilus which was not on my radar. Also the simple diverter might be just the thing I’ll need for the shower/sink connection.


I have the gen 2 Girard in my 550 build. So far we're doing the catch the cold water in the coffee pot thing. We have a road shower on the roof for warm weather showering. My fresh tank is only 20 gallons. We have just got this build up and running so time will tell. We are used to cold weather camping here (-20 and colder) so we are used to conserving water as we use blue jugs as the water system is winterized. I have my Girard set at 124F and it takes about 1- 1.5 liters until its running hot.