Community Forums

1badhemi · 07-04-2018, 01:22 PM

If the water is running it should always be hot but it doesn’t seem to stay hot it starts out hot then it’s cold and it doesn’t stay hot is it electric and gas I hear it turn on but it doesn’t seem to stay running in the gas setting the wife is tired of taking cold showers 2017 Fleetwood storm 32 a

wmckinley · 07-04-2018, 02:00 PM

You didn't say what brand of tankless.

When I installed a suburban IW60 in my winnie, I had the same problem.It would start hot then go cold. Tried calling suburban and they told me to basically take a hike. Pulled that out and replaced it with an Atwood. Still had close to the same problem. Finally I went thru checking water pressures.

The shore water pressure was Too low and the pump pressure was too low.

Adjusted the pump per instructions and increased it's output pressure up to factory max. No more problems when running on pump.

Where I did the install, I couldn't get the pressure up high enough for the water heater to work reliably.

Only had that problem again at one campground. I just filled my tank and ran off of the pump.

The Suburban does seem to be a little more finicky to the water flow than the Atwood.

DW is Happy IE I am Happy.

Still got the suburban laying around.

Check your water flow rate and your pump setting. I have the SHurflo pump, easy to adjust. Instructions on the web and in the manual for it.

1badhemi · 07-04-2018, 02:11 PM

Thanks its a Atwood heater ill check my pump you would think that hooked up to city water i would have plenty of pressure and running pump at same time

wmckinley · 07-04-2018, 02:27 PM

If the pump runs when properly adjusted and you are hooked up to shore water at the same time it could be caused by the shore water pressure at the coach is too low (kinked line, supply valve not open all the way or just low pressure), Or your pressure regulator going into the coach is set too low.

Personally I don't like to have the pump turned on to compensate for low city water pressure. I'd rather run off just the pump, then refill the fresh tank as necessary.

I added a water pressure gauge to my coach inlet so i know what i get. If it's below 55lbs, I run off the pump. My regulator is adjusted to 60lbs. Also make sure you have a good regulator, the cheapie non adjustable restrict water flow.

wmckinley · 07-04-2018, 06:28 PM

One additional. The Atwood has a small vent tube on the purge fan fan switch , sticks out thru a hole in the external panel. Make sure the vent tube is clear.

jrocker · 07-05-2018, 08:00 AM

We have the Atwood on our coach and it would be difficult for me to express just how much i despise this thing.

After a year and a half of research, whining, and tinkering, I've learned just enough about it to wish I had the money and time to install something different.

3 things influence the water temperature.

1. incoming water pressure. As mentioned, anything less than 55psi means a cold shower. Ditch that cheap camco pressure regulator and buy something adjustable with a pressure gauge.

2. Ambient temperature/water temperature. This one is frustrating for someone who uses the coach year round. You can adjust the modulating valve (straight up and down is "max") to compensate for ambient/water temperature. Documentation says to set it at max when the outside temp is between 45 and 70f. The factory setting is at the midpoint, and functions well in that spot during the summer months. It's hit or miss at max when the temp outside is below 40f.

3. Water flow. Atwood calls for between 1 and 1.25 gpm. Anything outside that range, and you're fighting an uphill battle. And don't just think about the gpm on your faucets. Other things can influence this. Such as, increasing the cold water input too quickly, or adding too much cold water to the flow. And I have also found that if I leave the outside shower on (not actually flowing, but on) it will interfere with the flow when I'm running on the pump.

Hope this helps.

wmckinley · 07-05-2018, 12:27 PM

x2 on Jrocker,

As a general rule this applies to all Tankless Water heaters. I've have been using them starting with stick and brick models since 1998. There is one other thing that i have found.

Our last trip we were dealing with temps into the 20's and the DW was mentioning that the water wasn't warm enough for her. (she likes really hot showers). Water flow was good, water pressure was good, incoming water temp was naturally a little low.
I put a monometer on the gas rail of the water heater. Found that the propane pressure was low. per manual.
Gas Manifold pressure tap on burner assembly.The gas manifold pressure at this tap is 9” w.c. =/- 0.5” w.c. for both the
OD50 and the OD50CW models.

Checked my main line and it's pressure was low. My main pressure regulator was failing.
Replaced the pressure regulator at the tank, now as is well.
Another bit of advise is to get rid of the stock shower valve. I replaced mine with a hydro-static valve. It resolves the temp up and down.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Jrocker, the reason the outdoor shower affects it, is because when the supply valves to the shower are turned on, but the water flow at the shower head is turned off, the cold water will back flow thru the hot water valve bypassing the water heater.

I spent a lot of time tweaking my system and I now can say, no more complaints.
Hope you get happy !

1badhemi · 07-10-2018, 11:32 AM

Well I took off the cheap regulator and the heater worked just fine I guess it was a low pressure problem I’ll do some adjustments on the the pump for dry camping and get a adjustable regulator thanks for your replies to all.