Hot fiberglass above water heater vent

[Paradox21]

Hi all. New to the forum. I picked up my 2021 17B in August. The first time I started the 2-way Suburban water heater using propane it ignited on the second try, ran a full cycle, and shut off. Water was nice and hot. However, when I felt the fiberglass on the outside of the trailer about 4 cm above the hot water heater vent, the fiberglass was so hot I couldn't keep my hand there for a second. (Heater was off and no more steam was present.) It was burning hot (and my hands are not sensitive to heat by any means)! I measured the temperature of the fiberglass with an infrared temperature gun. It was 136oC (276oF)! I tested a neighbors infrared gun a few days later after firing up the heater again. The temperature read about the same. I called Escape to see whether this was normal. They had me send a few photos to determine if it was installed properly. They said the installation looked good but “Test this water heater frequently prior to any trips and monitor it but this shouldn’t be an issue.” I asked another owner of a 2021 17B whose trailer was delivered a few weeks after mine if they could check the fiberglass above the water heater the next time they fire it up. They kindly agreed and reported that it was warm, but they were able to keep their hand on the fiberglass without a problem. So, my question is, has anyone noticed intense heat in the fiberglass above the water heater vent after a cycle finishes? It would be very comforting to know that this is normal. It would be very important to know if it’s not. Thanks for reading.

[gbaglo]

I have a 17B with Suburban water heater.

But, I don't know what you mean by "cycle". My water heater is either on or off, with a manual switch. I turn it on 20 minutes before I need hot water and turn it off when done.
And, where is this steam you mention coming from?

[Centex]

Originally Posted by gbaglo

.... But, I don't know what you mean by "cycle". ...

If one turns on the water heater but does not use any hot water the burner will fire until the thermostat set-point is reached then turn off. One might call that a "full cycle". As hot water is used or the tank 'cools', if the WH is left "on" at the interior control that 'cycle' of burner-firing will repeat.

Maybe not your use-habit, yes it's wasteful of propane if the hot water is not being used, but the WH is designed to allow that for an indefinite period, just like a residential tank-type WH, and should do so without causing any untoward overheating anywhere.

[Paradox21]

Yes, thanks. That is what I referred to as a "cycle".
Steam may not have been the proper description. By "steam" I meant the hot, humid heat coming from the exterior water heater vent.

[MVA]

Originally Posted by Paradox21

Yes, thanks. That is what I referred to as a "cycle".
Steam may not have been the proper description. By "steam" I meant the hot, humid heat coming from the exterior water heater vent.

Have you opened the cover and then run a cycle on the hot water heater? Clearly be careful due to the high temperature you have observed, but my first assessment would be that the relief valve has failed, allowing steam to escape.

Edit - when you cycle the HW heater, if the relief valve did fail, burning steam will be exiting the relief valve, hence handle with reasonable caution. A partially stuck open valve could result in what you are observing.

[Iowa Dave]

That seems pretty hot to me. When you said “steam” I thought maybe your relief valve at the top of your heater had malfunctioned or had a bad face on the seal and was actually giving off steam. Perhaps the thermostatic shut off is malfunctioning and allowing the burner to keep running well past the safe temperature shutoff point. And it’s running too long. There should be reference somewhere as to how hot the straight hot water will be on a normal cycle. Does that show up in any of the manuals. I know straight hot water in our 21 is pretty hot maybe 150 or so. But the outside above the tank is not all that hot. I would attempt to figure it out rather than just “watch it”. Nobody including kids should have a chance to actually burn themselves on a new trailer. 276 is way to hot.
Iowa Dave

[Centex]

Originally Posted by Iowa Dave

.... There should be reference somewhere as to how hot the straight hot water will be on a normal cycle. ....

FYI from the SW6DEL (and other similar models) Installation and Operation Manual:

"The thermostat on your water heater is not adjustable. It is a temperature sensing limit designed to maintain a water temperature of 130̊F (54̊C)."

Then there is separate mention of this:

"The model water heaters listed above are equipped with a high temperature limit as a cut-off device. Temperature above 180̊F will cause manual reset button to trip shutting down main burner." [sic]

[AKCamper]

Doesn’t the hot water heater have a deflector to keep the heat away from the fiberglass is that in place on yours

[BC_Camper]

I also noticed the fibreglass gets very hot above our water heater from venting gas when it runs a longer duration to heat the water on the initial cycle. I was concerned it would damage the decal it is so hot. We only used it a few times so far and has not yet caused damage. Believe the vent deflector is in place as it should be.

[Vermilye]

Originally Posted by AKCamper

Doesn’t the hot water heater have a deflector to keep the heat away from the fiberglass is that in place on yours

I had one on my generation 1 17B, however since the generation 2 (my 21C) doesn't have the ridge designed into the generation 1 molds located just above the water heater exhaust, I don't have a deflector and don't think they are included anymore.

[Iowa Dave]

I knew there were cutoff temps but didn’t remember what they were. I’ve never noticed our heater getting excessively hot but that said I’ve never put my hand right above it.. Maybe a person could design a quick attach/detach deflector to hang onto the exhaust port or plate. Good Luck
Iowa Dave

[rubicon327]

Originally Posted by Paradox21

Hi all. New to the forum. I picked up my 2021 17B in August. The first time I started the 2-way Suburban water heater using propane it ignited on the second try, ran a full cycle, and shut off. Water was nice and hot. However, when I felt the fiberglass on the outside of the trailer about 4 cm above the hot water heater vent, the fiberglass was so hot I couldn't keep my hand there for a second. (Heater was off and no more steam was present.) It was burning hot (and my hands are not sensitive to heat by any means)! I measured the temperature of the fiberglass with an infrared temperature gun. It was 136oC (276oF)! I tested a neighbors infrared gun a few days later after firing up the heater again. The temperature read about the same. I called Escape to see whether this was normal. They had me send a few photos to determine if it was installed properly. They said the installation looked good but “Test this water heater frequently prior to any trips and monitor it but this shouldn’t be an issue.” I asked another owner of a 2021 17B whose trailer was delivered a few weeks after mine if they could check the fiberglass above the water heater the next time they fire it up. They kindly agreed and reported that it was warm, but they were able to keep their hand on the fiberglass without a problem. So, my question is, has anyone noticed intense heat in the fiberglass above the water heater vent after a cycle finishes? It would be very comforting to know that this is normal. It would be very important to know if it’s not. Thanks for reading.

Does your hot water temperature seem normal (i.e. 130F)? Is the WH completely stock or did you add an aftermarket bug screen over the exhaust like many owners do?

[Paradox21]

I haven't opened the heater door and run a cycle. I can give that a try to see what happens.

[Paradox21]

I'm wondering if the first shut off valve is not working when the temp hits 130oF but the high temperature cutoff valve is working at 180oF. Is there a way to test this? I'm not sure whether the temperature of the water was hotter than 130oF but will pay more attention next time I start the heater. I haven't modified the heater in any way.
I'm worried about the decal too. I can't imagine it can take that much heat too many times.

[rubicon327]

Originally Posted by Paradox21

I'm wondering if the first shut off valve is not working when the temp hits 130oF but the high temperature cutoff valve is working at 180oF. Is there a way to test this? I'm not sure whether the temperature of the water was hotter than 130oF but will pay more attention next time I start the heater. I haven't modified the heater in any way.
I'm worried about the decal too. I can't imagine it can take that much heat too many times.

If the secondary safety was tripping at 180F it needs to be manually reset. Water heater wouldn’t work until this was done.

[brroberts]

Fired my water heater up on gas for the first time today and let it run one cycle, approximately a half hour, and my fiberglass barely got warm to the touch. In the 60’s F here and a cool breeze.

I’ve heard water heaters whine in electric, but never on gas. I had a 1.8KHz low level whine while the burner was on.

[Paradox21]

Thank you everyone for your replies and suggestions. I will look into some of the things that were brought up. Hopefully we will be able to figure this out.

[JeffreyG]

I took my 2021 E-19 out for a first camping trip this weekend. Having seen this thread, I checked the side of the fiberglass right above the hot water vent area right after I first turned the heater on. It was too hot to touch.

I'm not keen on the fiberglass getting that hot. I made a quick test where I sandwiched a piece of aluminum foil in the door, and that totally resolved the hot fiberglass.

I think I'll just bend up a small piece of metal to act as a deflector, and rivet it to the hot water heater door flap above the vent area.

[rubicon327]

Originally Posted by JeffreyG

I took my 2021 E-19 out for a first camping trip this weekend. Having seen this thread, I checked the side of the fiberglass right above the hot water vent area right after I first turned the heater on. It was too hot to touch.

I'm not keen on the fiberglass getting that hot. I made a quick test where I sandwiched a piece of aluminum foil in the door, and that totally resolved the hot fiberglass.

I think I'll just bend up a small piece of metal to act as a deflector, and rivet it to the hot water heater door flap above the vent area.

This is the deflector that Escape used to supply on earlier trailers. It appears a factory addition and not available from Suburban. Not sure why they stopped besides the minor mold change that made the water heater now flush versus slightly recessed under the ridge.

[Patandlinda]

Originally Posted by JeffreyG

I took my 2021 E-19 out for a first camping trip this weekend. Having seen this thread, I checked the side of the fiberglass right above the hot water vent area right after I first turned the heater on. It was too hot to touch.

I'm not keen on the fiberglass getting that hot. I made a quick test where I sandwiched a piece of aluminum foil in the door, and that totally resolved the hot fiberglass.

I think I'll just bend up a small piece of metal to act as a deflector, and rivet it to the hot water heater door flap above the vent area.

That to me doesn’t look good . If mine I would have a deflector above to reflect the heat . Ask Escape if you can get one or make something . Many of us can help you out with pictures . Did they remove it for looks ? Recently just watched a fiberglass boat ,a new one go up in flames real fast . Can find on you tube , Barefoot doctors . Scared the heck out of me . I would be proactive in this but that is just me . Pat