Water does NOT staying hot.

TXguy

Member
Water NOT staying hot.

This has probably been answered but don't feel like searching hundreds of posts. I've only had the electrical button on for hot water heater, never used propane. If I leave button on all night, the hot water is warm to cold. Shouldn't it stay hot? Called mfg but did not have model number. Where do I find that?

Bought 2017 Prowler Lynx 25LX, used about one month by previous owner, so no longer under warranty. My first RV. Why didn't it come with a manual? Dealership gave me a USB, with generic, 2015 Heartland info on it. Doesn't help. I need to know WHERE hot water heater is, where's the model #, etc. I've got winterized insulation, & cover on underside, don't want to be tearing that stuff out looking for a water heater. Sure wishing this info was in a manual.

Tech said thermostat likely defective. I'm a do-it-yourself guy, but wish I had a manual to look at first. And, DSI FLT light on. What the hades does that mean? Oh, it's not referenced on my practically useless Heartland USB.

Anyone have any advice?
 
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TXguy

Member
Model # found on water heater

In my first & only post, which is still waiting for moderator approval, I was complaining about location of water heater & model number being a mystery (Atwood, by the way). Well, duh, I opened the outside cover, to apparently the hot water heater, there was the info needed. Model #, manual numbers (5 different ones?). Still not sure why water won't stay hot, but location of heater now known. Found some pictures in manuals, linked on this forum too. Finally, a picture to look at. Getting there. Thanks for putting up with the newbie.
 

danemayer

Well-known member
It may be that you don't have manuals because the previous owner didn't leave them in the trailer for the next owner.

Heartland uses Suburban water heaters on some trailers, and Atwood on others. If you walk around your trailer, you'll probably find a square metal panel with vents on a side wall. There's typically a catch that allows you to remove the cover. Inside, you'll find things like model/ser# plates, reset buttons, pressure/temperature relief valve, and a drain plug. If you have a Suburban unit, the drain plug has an anode rod that goes inside the tank. Atwood has just a plug.

We have manuals for both Atwood and Suburban in the manuals section of the forum, here.

The water heaters usually have a combination thermostat/overtemp cutoff. If your heater gets water hot, but then it shuts down, it may be a problem in that assembly. But there are other possible causes.

If you have a Suburban unit, we have a troubleshooting guide that will help you figure out what's wrong. It's here.

Note that lukewarm water can also be caused by having the outside shower faucets open, allowing hot and cold water to mix. The same thing can occur if the Water Heater Bypass valve(s) are not in the correct position.

DSI FLT is an indicator to let you know that the Direct Spark Ignition was attempted and failed. FLT stands for FAULT. DSI FLT would suggest that you turned on the propane side of the water heater but may not have had any propane reaching the burner.
 

TXguy

Member
Re: Water NOT staying hot.

What I thought, that owner did not leave manual.

My hot water heater is an Atwood. Yes, I opened the outside cover, found model # & 5 different manual numbers. I'll look up later.

But why would my DSI/FLT light be suddenly coming on? I always turn on the Electrical switch; never used propane once, on hot water heater. Apparently something in that unit is malfunctioning, water won't stay hot, now this mysterious warning light. Stinks when a NEW TT isn't working right. Just bought a practically new TT, & it has defects; regretting my choice. Wondering if this isn't why the previous owner bought new, & traded back in one month later.
 

TXguy

Member
Re: Water does NOT stay hot, HOW to test & fix

Well, judging by the name, thermostat/overtemp cutoff, sounds like the culprit. Overtemp cutoff? When my water is heated, it is scalding, so, as it sits, the system shuts down?

Now I'll need to scour manuals on this site & see if I can locate thermostat. Is it adjustable or electronically pre-set? How to test if defective? So many questions.
 

danemayer

Well-known member
Re: Water does NOT stay hot, HOW to test & fix

Well, judging by the name, thermostat/overtemp cutoff, sounds like the culprit. Overtemp cutoff? When my water is heated, it is scalding, so, as it sits, the system shuts down?

Now I'll need to scour manuals on this site & see if I can locate thermostat. Is it adjustable or electronically pre-set? How to test if defective? So many questions.

Atwood thermostats are preset to 140 (F) and cycle between 115 and 140 (F). You may be able to replace it with an adjustable thermostat that can be set to your preference within a range up to 150 (F). I think the overtemp or thermal cutoff on an Atwood is a one-shot thermal fuse that must be replaced if it ever opens. So if you're able to restart the water heater, on electric, it's probably not the overtemp sensor.

Could be the thermostat opening at 140 (F) and not closing when the water gets down to 115 (F). But before tearing into the water heater, at a time where the water is cool and the heater appears to be malfunctioning, carefully open the pressure/temperature relief valve and collect a little water directly out of the tank. If it's cool, you have a heater problem. If it's hot, you're mixing cold water with the hot somewhere outside of the water heater.
 

TXguy

Member
Re: Water does NOT stay hot, HOW to test & fix

Atwood thermostats are preset to 140 (F) and cycle between 115 and 140 (F). You may be able to replace it with an adjustable thermostat that can be set to your preference within a range up to 150 (F). I think the overtemp or thermal cutoff on an Atwood is a one-shot thermal fuse that must be replaced if it ever opens. So if you're able to restart the water heater, on electric, it's probably not the overtemp sensor.

Could be the thermostat opening at 140 (F) and not closing when the water gets down to 115 (F). But before tearing into the water heater, at a time where the water is cool and the heater appears to be malfunctioning, carefully open the pressure/temperature relief valve and collect a little water directly out of the tank. If it's cool, you have a heater problem. If it's hot, you're mixing cold water with the hot somewhere outside of the water heater.

That makes sense, thanks for the advice.
 

For20hunter

Pacific Region Directors-Retired
Make sure that your outside shower faucet valves are both closed. If you have either of them open, the water will cycle through those and mix the cold with the hot.

Rod
 

TXguy

Member
Re: Water NOT staying hot.

Make sure that your outside shower faucet valves are both closed. If you have either of them open, the water will cycle through those and mix the cold with the hot.

Rod

That sounds odd. If one was on, I'd have water running down the side of my TT. But no, both are off.

While you're on the line, if I never use propane, but only electrical on my water heater, why would the little DSI/FLT light all of a sudden be coming on?

But the original issue is the water not staying warm to hot, after a shower, & the electric switch still on, OR, if it's left on all night,
water is cold in the morning.
 

For20hunter

Pacific Region Directors-Retired
Re: Water NOT staying hot.

That sounds odd. If one was on, I'd have water running down the side of my TT. But no, both are off.

No, if your valves are on, but your button on your sprayer is off, no water comes out. The water just circulates through the system, mixing cold with hot. Trust me, this is for real.

Rod
 

TedS

Well-known member
Somebody else pushed the propane button 'on' by mistake or in error.
Trust For20hunter's response about both outside shower faucet valves being open.
 

Silverado23

Iowa Chapter Leaders
Re: Water NOT staying hot.

No, if your valves are on, but your button on your sprayer is off, no water comes out. The water just circulates through the system, mixing cold with hot. Trust me, this is for real.

Rod

Having the water heater bypass valves in the wrong positions could also cause similar results. Some hot water mixing with cold and then eventually all cold.

If you have a three valve bypass, the middle valve between the hot and cold lines must be closed or you will get the hot/cold mixing issue. Or possibly just cold water.
 

For20hunter

Pacific Region Directors-Retired
Re: Water NOT staying hot.

Having the water heater bypass valves in the wrong positions could also cause similar results. Some hot water mixing with cold and then eventually all cold.

If you have a three valve bypass, the middle valve between the hot and cold lines must be closed or you will get the hot/cold mixing issue. Or possibly just cold water.

Another great suggestion!
 

TandT

Founding Utah Chapter Leaders-Retired
Re: Water NOT staying hot.

This has probably been answered but don't feel like searching hundreds of posts. I've only had the electrical button on for hot water heater, never used propane. If I leave button on all night, the hot water is warm to cold. Shouldn't it stay hot? Called mfg but did not have model number. Where do I find that?

Bought 2017 Prowler Lynx 25LX, used about one month by previous owner, so no longer under warranty. My first RV. Why didn't it come with a manual? Dealership gave me a USB, with generic, 2015 Heartland info on it. Doesn't help. I need to know WHERE hot water heater is, where's the model #, etc. I've got winterized insulation, & cover on underside, don't want to be tearing that stuff out looking for a water heater. Sure wishing this info was in a manual.

Tech said thermostat likely defective. I'm a do-it-yourself guy, but wish I had a manual to look at first. And, DSI FLT light on. What the hades does that mean? Oh, it's not referenced on my practically useless Heartland USB.

Anyone have any advice?
The electric function of your hot water heater should heat the water in about 1 hour. Yes, it should stay hot indefinitely if you have the switch on.
For a quick heat up or if you don't have power use propane. Propane will heat up your water in about 15 minutes. Trace

Sent from my SM-G955U using Tapatalk
 

kowAlski631

Well-known member
I would advice you to consult a contractor for some better suggestion.

This forum and the Heartland owners have saved us a lot of time and effort over the years. You see, these people have first hand experience with how to diagnose and repair commonly occurring issues. We were waiting for a mobile repair service to arrive when our water heater was producing only tepid water. A fellow owner stepped forward and told us to check the outside shower. Bingo.

I'm not sure why you believe a contractor is more knowledgeable than people who have seen the same situation and assisted with resolution, but we're here to tell you that the people on this forum try to help and do not try to harm.
 
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