27fbq Tankless Water heater woes...

[WVDude]

I have searched the forums, and couldn't find an immediate fix. But. Our first trip we had really good water pressure (ruptured an old water hose!) and had great water pressure and hot water at the kitchen sink and shower.

We went to a state park last weekend and sadly had no internet. But also low water pressure and only had hot water in the bathroom sink.

After getting home, and researching. Found possible solutions like turning on the hot water in the bathroom on a trickle. But it is rather frustrating.

So, what have YOU discovered as a solution to the problem?


Oh, and when I got home. Hooked up to my water at the house. Had good pressure and had hot water in the shower and kitchen sink. Then we stayed in the camper at home Sat night with the hose hooked up, and had not 100% success with hot water .

[Merlintiaga]

Hi WVDude. Sounds like you're wrestling with a Girard on-demand water heater. I have the same unit and *really* dis-like it. We have found that the best way to use it is to set the water temperature to 102, then when you want warm water (shower or sink), run the hot water on full (no cold). If the flow rate through the water heater drops below 1 gallon per minute, then the water heater shuts off. This is an inherent issue with the Girard unit.

Also, be sure to NOT use a water pressure regulator. The Globetrotter has a regulator built in and you cannot run two of them and get good flow in the trailer. More is not better in this case.

[daleyocum]

When we have low water pressure from the park we turn on the pump as well. The pump will kick on if the pressure isn’t sufficient and the two water sources will mix.

When you have full hookups, the idea of turning on the sink partially is useful advice. When you don’t have hookups it will take some plumbing changes to dump water back into the fresh tank to avoid wasting that water. The showermiser is what some have resorted to. If you don’t care about the color shifting feature, you can make your own with commonly available plumbing parts.

These tankless water heaters sound great on the showroom floor but are definitely not a step forward over the tried and true 5gal water heaters in older RVs.

[Monoman]

We swapped out the Girard for a Truma and have been 100% happy. Pricey but worth it to us. AS should just use the Truma.

[Life is a Highway]

Happiest day of our life watching our Girard leave our Airsteam in the back of the Truma service techs van.

The Truma has performed perfectly since day one and one year later still gives on demand hot water.

We installed the IRVWPC pump module trying to solve the Girard problems. And while it did not fix the Girard
it did solve noisy water pump and provided non pulsing water control even at a drip

[bradleypkm]

How much was the Truma?

[PaulBristol]

On-demand water heaters are complicated. Getting the microprocessor logic correct is a problem. Girard did not. Truma did.

Heat turns "ON" when flow rate is high enough. It takes a few seconds for the burner to light, then cold water in the pipe needs to be flushed.

No pressure from the campground faucet means water will not flow fast enough to trigger the burner. Use on-board pump from holding tank to boost flow. Turning a second faucet "ON" may increase the flow enough to trigger the burner.

Burner must be hot enough to heat cold water. Near freezing water may not get warm enough.

Airstream is changing, but not to Truma. I have a 2025 model with a Suburban IW60RL recirculating water heater. Hot water is instantly available at all taps even at low flow. This is far better than the old 6 gallon tank heater. It is convenient and miserly with water for boondocking.

[Monoman]

Originally Posted by bradleypkm

How much was the Truma?

I don't remember exactly but it was $300 off installed when scheduled at the Tampa RV show.

[Forester2]

Took my failed Girard apart today to see where it fail. Don't think I could design a better water trap if I wanted to.

[PaulBristol]

Originally Posted by Forester2

Took my failed Girard apart today to see where it fail. Don't think I could design a better water trap if I wanted to.

That is probably why AS requires a blow out with enough pressure for winterizing.

On demand heaters and recirculating systems are complicated in many ways. Does a Truma have a recirculating pump?

[Forester2]

Failure wasn't from winterization (which I blow lines and pump antifreeze) but from using trailer during cold snap. What didn't work was antifreeze system in unit where it automatically turns on when water temp drops.

[SVTRIDE]

Originally Posted by bradleypkm

How much was the Truma?

$1826.21 otd at their Elkhart Indiana US headquarters.

[PaulBristol]

Originally Posted by Forester2

Failure wasn't from winterization (which I blow lines and pump antifreeze) but from using trailer during cold snap. What didn't work was antifreeze system in unit where it automatically turns on when water temp drops.

My Suburban has a recirculating pump. If the Truma does not have a recirculating feature, the burner "ON" in freezing temperature may not protect everything.


Also, mine is installed inside the cabin wall. There is no door to the outside. I think Truma may make models for both kinds of installation. Hopefully Truma provides good door insulation for those models, but a little ambient heat is still required. For connecting pipes inside and outside the unit.

[jlokanis]

Originally Posted by PaulBristol

My Suburban has a recirculating pump.

Did this come with your unit or did you do an upgrade? I would expect adding the recirc feature would require must more extensive plumbing changes than just swapping out the water heater.

We have a 2024 with the Girard and it does not work very well for us when boondocking. We have to run so much water to get it to heat that our grey tank fills up very fast. Fresh is not the issue since we could always add some with a 5gal jug if needed but there is no way to get rid of the grey without a tote and trip to the dump station. So, the old school tank heater seems like a better solution for boon docking than a recirculating pump. But I would love to be wrong about that.

[PaulBristol]

The Suburban with recirculating pipe loop was builtin from the factory by AS.

[jlokanis]

Originally Posted by PaulBristol

The Suburban with recirculating pipe loop was builtin from the factory by AS.

yeah, that is a nice feature in the TW and some of the newer units. I missed that feature by one model year. Not really possible to retrofit that I suspect.

I guess I will live with the Girard until it dies and then replace it with a tank model.

[waninae39]

the girard needs a min amount of water pressure, else no hot water

we set the controller to 41c (max is 51c)
then we set shower to full hot

then when we shower it comes out fines, as 41c is just right

[Ironsinker]

I’ve seen others with this problem and what they do is use their fresh water tank and their pump. They only use the city water to fill the tank. You’re not alone and many many people have this issue.

[jlokanis]

Originally Posted by Ironsinker

I’ve seen others with this problem and what they do is use their fresh water tank and their pump. They only use the city water to fill the tank. You’re not alone and many many people have this issue.

We were dry camping so we were already using the fresh tank and the pump. I have not tried it with city water hookups yet. Maybe a higher pressure input would help. It does eventually get hot when running with the pump but so much water ends up in the grey tank that it limits how long we can go between dumps. We will continue to experiment and hopefully can get it to work better.

[Merlintiaga]

Adding a recirculating loop in a 27FB is actually quite doable. I added one to my 27’ Globetrotter. There are two cross-trailer tunnels, one for plumbing and one for electrical. The plumbing tunnel goes from under the range to under the closet. I use a fish-tape to get from one to the other, then pulled a para-cord through. Then I ran the para cord *through* the PEX pipe and tied a washer to the end. I was then able to literally pull the cord to pull the PEX pipe. It wasn’t nearly as difficult as I thought it was going to be. I am adding a recirculating system to my Girard but it could just as easily be used for the new suburban recirculating water heater.