Tankless hot water heater, it's a good thing.

[jonrjen]

I see more post of owners complaining about the Garrad Tankless Water Heater. But, we just spent our first night out in the new Wildcat and really enjoy the almost instant endless supply of hot water.


Yes, it comes with a learning curve and yes the instructions of it's use is not the best of written directions, but if you take the time to talk to others who are knowledgeable of how the system is designed to work it is a great feature to have. It does take alittle getting used to from the sound it makes as it fires up and runs.


I do know one feature that should come with the tankless water heater, that is a larger grey water tank.

[kimmccormick]

we recently bought a 2008 wildcat and immediately had to repair h20 pop off valve. I was wondering about replacing the h20 tank with a tankless h20
can you go into more detail how it works.
I need knowledge to make a wise choice
thank you

[Kaadk]

Brother-in-law's got the tankless in his wildcat. We've debated the pros and cons between his setup and the Suburban in mine. Basically they boiled down to:

Tankless:Pro: Never run out of hot water
Con: Only runs on Propane

Tanked:Pro: Can run on electric and save propane
Con: Possible to run out of hot water.

Depends what matters to what people.

[EricInColorado]

No electric on a tankless???? That would kill it for me. When on shore power, I love my hot water. But when on propane, it is fired up very sparingly. And then we use the hot water sparingly as well!

[Kaadk]

I don't know if some models have it, but I can say for certain his does not.

Though, a tankless on propane is more fuel efficient than a tanked on propane. So if you don't have shore power the tankless is the better approach.

[jonrjen]

Sorry for the delay in getting back to this post, but I have been in the shower with unlimited hot water all day....LOL, just kidding.


IN the past we were also one of those Rv'ers who like leaving the water heater on electric and letting the camp ground pay the bill, but we are really liking this endless hot water system. You just got to make sure there is no air in the water lines, that you have a good steady flow of water and the water pressure stays constant.


It take a little getting used to adjusting the temp of the hot water by control of the flow of the hot water volume and not by blending cold water in to the mix.

[whj77372]

It is much harder to heat water in a tankless system with electricy. The propane does a much better job. That is why we have a tank system. We don't turn it on until we need hot water and turn it off when we are done. I mostly shower at RV park bath houses but my better half only uses the shower in our fiver.

[ependydad]

Originally Posted by EricInColorado

No electric on a tankless???? That would kill it for me. When on shore power, I love my hot water. But when on propane, it is fired up very sparingly. And then we use the hot water sparingly as well!

I read this often- how much propane does the water heater really use? We've ran ours on both and haven't seen any kind of noticeable usage until we start to fire up the furnace and then we use it like (insert witty analogy here).

[Kaadk]

Originally Posted by ependydad

I read this often- how much propane does the water heater really use? We've ran ours on both and haven't seen any kind of noticeable usage until we start to fire up the furnace and then we use it like (insert witty analogy here).

Let's put it this way:

- I picked up the TT in April,
- Ran WH on propane only for any trip between April and August, when I got the WH electric switch fixed.
- Ran the fridge on propane for all stocking and travel, only switched to elect when at the site
- Used the Sidekick about 2x a day, Stove about 1x a day for cooking meals.

- Finally ran through my first 20lb tank near the end of September, after turning the furnace on.

Note, that usage pattern was over ~20 nights camping. All in all, I'd have to say the suburban is not propane crazy.


Still, it would be nice to see a tanked/tankless hybrid, where the tank is heated by electric and supplemented by a propane ondemand approach like the tankless. This should be doable. Since a tankless works on a delta approach, if the water's already hot the tankless won't need to kick on and heat the water further, but if it's not, (like if without electric) then it could do the job. Just a matter of turning off the propane side of a suburban and then putting the tankless system downstream from there.

[EricInColorado]

The geek in my thinks designing the hybrid unit is a fun Thermodynamics problem. (Sad thing is, I'm fascinated by thermodynamics, but never took the class while getting my BS in Civil E. That was dumb.)

[Kaadk]

Originally Posted by EricInColorado

The geek in my thinks designing the hybrid unit is a fun Thermodynamics problem. (Sad thing is, I'm fascinated by thermodynamics, but never took the class while getting my BS in Civil E. That was dumb.)

Interesting. Thermodynamics was a required first year Eng course for us, before we supposed to pick a particular branch of Eng to study. (Myself? I picked Comp Sci. Turns out I wasn't a very good Eng, but I did have a knack for software. )

I don't know what comes in the RV, but in my studies to replace the home HW tank I've found they come in two flavours:

1) Constant burn - Flame turns on when water flows, turns off when not. Rate of flow controls amount of heat transfer. In this system, the less the HW is turned on, the hotter it gets.
2) Variable burn - A thermocouple measures the temp of the incoming water supply and adjusts the flame height accordingly. More expensive option but produces a more constant temp on the output side.

For the hybrid to work, you'd want to follow the design of #2.

[cadman99]

Don''t think you are going to get an electric tankless for an RV - requires 240VAC and 54amps for a small one.

[SKnight]

Originally Posted by Kaadk

Still, it would be nice to see a tanked/tankless hybrid, where the tank is heated by electric and supplemented by a propane ondemand approach like the tankless. This should be doable. Since a tankless works on a delta approach, if the water's already hot the tankless won't need to kick on and heat the water further, but if it's not, (like if without electric) then it could do the job. Just a matter of turning off the propane side of a suburban and then putting the tankless system downstream from there.

Thats an idea! Have a tank that's electric only, feeding a tankless heater. When the temps from the electric heated tank drop, the tankless fires up. Hmmmm, honestly it shouldn't be too difficult.

[cadman99]

Tankless water heaters are activated by flow not temp.

[ependydad]

And, you're now talking about 2 water heaters in a camper with limited space. Good idea, but with our 10 gallon water heater- we honestly haven't had an issue with running out of water unless we shower back to back. Last 2 seasons, I've been able to hold my son to wash him without turning off the water and then continue to wash myself (sometimes I would "navy shower" other times, I'd just let it go). I've even seen that the new Sabres are offering a 12 gallon water heater.

[SKnight]

Originally Posted by cadman99

Tankless water heaters are activated by flow not temp.

Correct, but it would be no issue to add a thermostatic switch in conjunction with the flow switch to control the tankless. If both agree, there's cold water flowing, it ignites. No flow or it's not cold, it doesn't ignite.

Without the need for an exhaust, an electrically heated water tank could be mounted anywhere leaving the tankless mounted in the original location.

Just thinking out loud.

[Witch Doctor]

I think that either is good it really depends on how you camp. If you are hooked to sewer all the time That would be great use all the water you want. If you do not have a sewer your gray tank will still limit you to how long you let the water run. I have a 6 gal tank and with 2 people have never ran out of hot water, and my gray tank can go for 4 day's without dumping, Plus and minus for both. I have two propane tanks and really only fill up once a year if I need it or not. Suburban W/H are very eff. and really do not use much propane at all plus the electric option which I use all the time. There's good and bad in everything.