Truma hot water bug problems

Accipiter · 05-12-2020, 07:58 AM

I posted this on the Facebook page but it didn't seem any one had this problem but I know there are other RV's that have the Truma HWH. We just got our 19 ViewG just before the shut down and haven't been able to take it out yet. I was wondering if anyone had problems with bugs getting into the Truma hot water heater exhaust when the unit is in storage? If you have what did you put over the vent to keep them out because I can't find any bug screens for the Truma. It look easy to build one to cover the opening. I had problems with the older style water heaters with bugs plugging the combustion tube.

Winterbagoal · 05-12-2020, 09:44 AM

Good question. I had to add some light screening to the furnace intake/exhaust to resolve a brief bug infestation.
I thought the Truma exterior panel had a built in screen inside over the exhaust port, but just went out and looked, and it doesn't.
I'll be adding something, too, just in case. I haven't noticed any bugs in the exhaust problems to date, but I'm sure it's happened to someone. Got some stainless steel screen, 3/16", left over.

Accipiter · 05-12-2020, 02:22 PM

Thanks, I'm surprised no one have had the problem. I've used metal screen door material before on door before to keep Japanese beetles out before but I'm afraid it is too restrictive for the exhaust on the Truma.

Winterbagoal · 05-12-2020, 03:17 PM

I picked up a piece of bulk screen with 3/16" gaps at an Ace Hardware in Michigan when I needed something to keep the mud dawbers out of the furnace. Think it cost me about $1 for a piece that was about 8" by 36". I cut a rectangular piece that fits over both intake and exhaust furnace ports. So far, so good.
I'll try and see if I can somehow fit a piece under the Truma exterior cover. It looks like the plastic vent piece is screwed into the back of the larger square cover. The problem is the metal exhaust vent exiting the heater, fits into a horizontal slot cut into the back of the plastic vent attached to the cover. There's also what appears to be a rubber seal around the metal exhaust vent that makes contact with the plastic vents on the inside of the cover. Not sure how I'll cross that bridge, but I'll figure it out.
If/when I get it done, I'll let you know how I did it.

Winterbagoal · 05-12-2020, 04:22 PM

OK, I did this. Just cut a piece of the screen you choose to use to the approximate size (height and width) of the slot in the back of the plastic vent cover where the metal exhaust port fits, and gently press it into the slot, until it stays there. Might have to trim it a bit to get it to fit snug. Then when you close the outer vent cover, the piece of screen should be pressed against the metal exhaust vent, creating a seal to deter the bugs from entering.

Accipiter · 05-12-2020, 05:53 PM

I know what you mean by the obstacles around the vent. I figured if I think about it for a while, I can come up with something too. It just looks like a problem in the long run something will find a home in the vent.

Winterbagoal · 05-12-2020, 06:08 PM

Quote:

Originally Posted by Accipiter

I know what you mean by the obstacles around the vent. I figured if I think about it for a while, I can come up with something too. It just looks like a problem in the long run something will find a home in the vent.

Well, mine's covered up now. Thanks for the idea.

Good luck with yours.

bkg · 05-17-2020, 09:03 PM

Quote:

Originally Posted by Accipiter

I'm surprised no one have had the problem. I've used metal screen door material before on door before to keep Japanese beetles out before but I'm afraid it is too restrictive for the exhaust on the Truma.

Yes, I had this problem and I in fact was ahead of the game - so I thought. Where I am in southern Louisiana we have couple of nesting insects that love building nest in all kind of crevices; wasps and in particular - mud daubers. I was familiar enough with my new View to identify inviting areas for nest and the Truma grill was definitely one. Problem is there isn't any pre-made screens for the Truma like there are for the other brands. I found that the stainless steel refrigerator inlet made by Camco was about the right size of the opening, it's just longer than what is needed for the Truma. I picked the pack up from Camping World and cut the length to fit the Truma. I had to contour the screen some since the Truma vent actually extends into the exterior cover - once done it literally fit like a glove. I advise caution here if going this route; if the screen doesn't fit correctly it could crack the Truma cover if installed with too much pressure.
This process was done in late 2018. Imagine my surprise in late spring of 2019 when I notice the tell-tale signs of a mud dauber entering the Truma heater. Mud pellets on the louver of the Truma heater cover. I removed the cover and inspected the Truma. It took some hunting but I found the mud nest inside the copper heat exchanger. I was able to remove the nest with some effort. As to how the mud dauber was getting in; well the mud pellets were on the bottom louver, I neglected to consider the inlet air, I only covered the exhaust. I believed the remaining louvers were aesthetic. Plenty of screen left I cut more sections to fill the inlet opening but this took a little more work to get the screen to stay on the cover. A few drops of hot glue on the screen corners to the backside of the cover.
A year later - still nest free at the Truma. Still working on bug proofing other areas - without much luck.

Sorry for the long narrative

Bobby

Accipiter · 05-18-2020, 05:12 PM

Great ideas, I had problems on a 5th wheel years ago and when we got our View I could see problems with bugs getting into the unit. I was think of doing it the same way, if I follow what your are saying. I was going to preform the screen in a half rounded shape. then insert into the louvers. The hot glue is a good idea too. Thanks a bunch!!