Tankless water heater issue

BarbRN · 01-31-2021, 06:15 PM

Just purchased a 14 Aspect 27k. The shower goes from scalding to freezing. Any fix??

al1florida · 02-01-2021, 02:01 PM

Quote:

Originally Posted by BarbRN

Just purchased a 14 Aspect 27k. The shower goes from scalding to freezing. Any fix??

Very hard to help w/o more details.

* Make & model of water heater
* Operating on gas or elect
* Is the problem when on water hookups or when using the water pump and fresh water tank?
* Are you running the shower at full water flow?

BTW you should have a water temperature control knob somewhere inside the RV to adjust the water temp.

A tankless water heater on gas senses the water flow to turn on the flame. When the flow stops or has a very low flow the flame turns off and may go through a cool down cycle for 15-30 seconds. The flame may not start during the cool down cycle even if the water flow goes back up so you will have cold water for a while. At least that is what the Girard water heater we had in a new-to-us RV. I removed that 'piece of junk' water heater & installed one with a tank.

BarbRN · 02-02-2021, 06:02 AM

Quote:

Originally Posted by al1florida

Very hard to help w/o more details.

* Make & model of water heater
* Operating on gas or elect. Electric
* Is the problem when on water hookups or when using the water pump and fresh water tank? Yes
* Are you running the shower at full water flow?
Not totally full but close
BTW you should have a water temperature control knob somewhere inside the RV to adjust the water temp. We do

A tankless water heater on gas senses the water flow to turn on the flame. When the flow stops or has a very low flow the flame turns off and may go through a cool down cycle for 15-30 seconds. The flame may not start during the cool down cycle even if the water flow goes back up so you will have cold water for a while. At least that is what the Girard water heater we had in a new-to-us RV. I removed that 'piece of junk' water heater & installed one with a tank.

Talked to
The rep yesterday. Suggested we purge the outside shower of air. Also we had it turned up to high. Need to back it off. Flame goes out at 131 to
Prevent scalds.
We would love to add a regular heater but space is an issue. . Where?

Morich · 02-02-2021, 08:19 AM

There are times when folks move into a new area and don't know that it is going to be a bit different. So the question becomes how much RV experience you have!
Is this a new field with new issues or are you familiar with the downsides of RV shower operations?

Getting the flow set and adjusted without leaving the water on and filling the holding tank took my wife a bit to get sorted, while I was far more used to the idea of "navy showers"!!!

We find the water lines running through cold spaces in our RV, does tend to make the shower water flow change far more than at home and combined with wanting to restrict the water used, it does work out quite different.

Is it a real problem or possible learning curve thing?

al1florida · 02-02-2021, 09:27 AM

Quote:

Originally Posted by BarbRN

Talked to
The rep yesterday. Suggested we purge the outside shower of air. Also we had it turned up to high. Need to back it off. Flame goes out at 131 to
Prevent scalds.
We would love to add a regular heater but space is an issue. . Where?

According to the Winnebago brochure for your RV, it originally came with a 6 gallon water heater:

Quote:

6-gallon electric ignition, 110 V/LP water heater
w/Energy Management System (EMS)

The tankless water heater is probably installed where the factory water heater was, so you could, if you wanted, remove the one you have an put in a 6 gallon water heater. It all depends on if you can get the tankless one to work the way you want.

al1florida · 02-02-2021, 09:45 AM

You could do some diagnostic work. Have one person out by the water heater and the other inside at the shower.

-- Take the outside cover so you can see and hear the water heater
-- Turn on the water in the shower while you watch/listen for the flame to ignite. Watch/listen for the flame to go out.

If it goes out while the water is flowing that is where the problem is. Not sure of the fix, the flame should not go out while there is a good amount of water flow.

Also check to see if the water heater continues to make a sound after you turn the hot water off in the RV. If you hear a sound like a fan running, that most likely means the water heater is in a cool down cycle and probably won't relight the flame until the the cool down cycle is over.

What make/model water heater do you have?

BarbRN · 02-02-2021, 06:38 PM

Now it won’t get hot past 80 degrees. Girard.

butch50 · 02-03-2021, 02:56 PM

Make sure you water heater is not in the bypass mode for winterizing.

BarbRN · 02-04-2021, 05:18 AM

I know. Somebody mentioned this. We cannot find a bypass on this first generation Girard but great suggestion

Pianotuna · 02-07-2021, 05:01 PM

Quote:

Originally Posted by BarbRN

Just purchased a 14 Aspect 27k. The shower goes from scalding to freezing. Any fix??

Add an accumulator tank after the water pump.

Atadnomad · 02-07-2021, 06:57 PM

Quote:

Originally Posted by BarbRN

Just purchased a 14 Aspect 27k. The shower goes from scalding to freezing. Any fix??

I had this happen on my 2016 micro mini. I cleaned out the screens on the bathroom faucet and the shower head, and it fixed the problem. There were several little granules and rocks in there and I think it was slowing the flow to stay one temperature. Good luck!

BarbRN · 02-09-2021, 03:05 PM

We considered this but it would require a different door and we have full body paint that would look awful.

BarbRN · 02-09-2021, 03:07 PM

48 years of experience and 9 RVs later.

al1florida · 02-09-2021, 03:20 PM

Quote:

Originally Posted by BarbRN

Now it won’t get hot past 80 degrees. Girard.

6 days ago you posted you can't get the water temp above 80 degrees.

Have you done any diagnostics, such as having someone watch/listen for the flame in the water heater while someone inside monitors the water temp?

Is 80* water temp only in the shower, or all faucets?

Any fairly descriptive details can you provide about the different symptoms you have seen would be helpful for those of us to provide assistance.

Details such as:
-- Water pump providing the water source, or shore water hookup?
-- Faucets on full or partial water flow?
-- Is the flame in the water heater on constantly or does it go on and off?
-- Any other details you can provide.