Curosity concerning Truma water heater straps

[FloraFauna]

During winterization (which makes me sad but thats a different topic), I found the strap holding the Truma water heater had broken on both sides in very symmetrical locations.  Easy to splice on a new strap but how did the failure happen?  I suspect these are fatigue failures and thus that same strap material is the wrong fix.  I also am not completely certain of the complete purpose of the strap other than to restrict the back of the water heater from jumping around.  Thoughts?

 

[Ollie-Haus]

Ours did the same thing, hull #1373. I replaced and added additional screws on the sides. We'll see if they hold up longer than the original strap. 

[Steve Morris]

Oddly, ours did as well. It seemed like pretty soft strapping material. 

[Geronimo John]

I am not a Truma guy, but PLEASE submit a ticket to OTT on this.  In my eyes this is a clear safety issue as unrestrained movement of this machine could impace one of the gas lines down there and cause a BOOM with your family personally involved.

GJ

[jd1923]

18 hours ago, FloraFauna said:

I found the strap holding the Truma water heater had broken on both sides in very symmetrical locations.

OTT certainly used the wrong material. Is the Truma heater currently hanging by the faceplate only? Better materials must be used for this application. This strapping material is for hanging pipe without a strength rating at only 28-gauge. Don't buy this stuff:

https://www.homedepot.com/p/Oatey-3-4-in-x-25-ft-28-Gauge-Galvanized-Pipe-Hanger-Strap-33530/301505501

Go with Simpson Strong-Ties made in the USA. You could mount two hard corners with straights or use their Coiled Strap. This item is 16ga and should be extremely strong. I have a coil of their lighter 22ga. I doubled the ends at mount points and used it to strap our inverter against the basement wall. The 22ga might be strong enough for this case but I promise the 16ga will be harder to bend but would never fail. They have an array of thicknesses, chose from 12, 14, 16, 18, 20, 22 gauges. The lightest 22ga is thicker, wider and stronger than what OTT installed. Buy this instead:

https://www.homedepot.com/p/Simpson-Strong-Tie-CS-25-ft-16-Gauge-Galvanized-Coiled-Strap-CS16-R/100375320

Edited Saturday at 07:01 PM by jd1923

[Geronimo John]

FloraFauna, Ollie-Haus, and Steve:

PLEASE today take the time to send OTT a safety ticket on this topic.

I have alerted Jason E off line.  But the system should be documented with your inputs and how you chose to fix your discovery.

My second worst fear is that other owners who do not read this forum will not know about this hazard.  To them, the only way they may become aware is if an OTT Tiger Safety Team gets the word out.  Your personal input is needed for that.

My WORST case fear is that a Truma trailer with this banding gets a cracked gas line and over time leaks enough gas for the interior to reach into the explosive range of concentration.   There are several possible ignition sources (I.E. some switches, Dometic three-way, or the gas heater) that could start a rapid disassembly event... with them inside.

Please share your experience with OTT via a ticket.

Thanks

GJ

 

Edited Saturday at 09:55 PM by Geronimo John
typos as usual....

[FloraFauna]

3 hours ago, Geronimo John said:

PLEASE today take the time to send OTT a safety ticket on this topic.

Will do so on Sunday.  I assume over the weekend no one will see it.

Your worst case fear is not unreasonable.  But I have concerns now about how much movement was happening even when the banding intact.  Obviously one doesnt want the unit bouncing around relative to the plumbing both gas and water but some of that is probably happening anyway.  So how best to dampen out and restrict movement.  I think the strap fatigued from repeated vibration suggesting things are bouncing around there.  Just fyi, i am a pretty slow driver with no recollection of single severe jolts.

Edited Sunday at 12:34 AM by FloraFauna

[FloraFauna]

5 hours ago, jd1923 said:

OTT certainly used the wrong material.

Yeah I think so too which is why I posted.  I am debating in my head whether locking it down to the bottom with angles in the corners as you suggest OR would it be better to have a slight flexibility?  I am concerned the strapping was stressed to the extent of two symmetrical fractures - that's kind of weird.  I have to look closer but yes perhaps it is only being held by the face plate now and the plumbing (not good).  I am going to wait to talk to OTT service before pursuing a fix.

[FloraFauna]

23 hours ago, Ollie-Haus said:

I replaced and added additional screws on the sides.

Were you able to do this without removing or loosening the furnace (in the bottom of my photo and allowing very little clearance around the one side of the strap)??

Edited Sunday at 01:10 AM by FloraFauna

[jd1923]

1 hour ago, FloraFauna said:

I am debating in my head whether locking it down to the bottom with angles in the corners as you suggest OR would it be better to have a slight flexibility?

Depends on what you have to work with, how far you can reach under and around it. I’d like it bolted down sitting on rubber bushings vs floating with only a pipe strap keeping it from bouncing down the highway!

What a LAZY installation! An on-demand heater doesn’t have the 6 gallons/50 LBS additional weight so they figured, “let’s just hang it.” And “Figured” is a polite word for lack of installation procedure. Shows the state of “professional installations” in the trades today! 🤣

I'm pretty sure our water heater is sitting on the floor. It’s wrapped in a foam casing, so it’s hard to tell.

i understand what GJ is stating, but I’ve never received a company email re a safety warning in 3 years except the one time when they mounted a Bulldog receiver not 7K rated on one hull (was Bulldog’s fault for mis labeling their product).

They’re not going to give you repair advice. You got this! 😎

 

Edited Sunday at 01:35 AM by jd1923

[Geronimo John]

The further back something is from the tongue, the rougher the ride is back there.  An unknowing driver's rear utilities on a washboard road can easily see 2 to 5 G's of verticle acceleration back there.  Which makes JD's statement that the wrong material used is on point.  I add to that that it was not properly engineered.  Hence care is needed in engineering a solution.  Hence the need for OTT's involvement.

The trailer axles and springs can help or hurt this issue.  Stiffer suspensions genarally makes payload shocks worse.  The exception is when the frame and axle slam together from having too soft a suspension.  Compliant suspensons help things a bit.  Having a heater hard mounted generally hurts.  Allowing it the ability to float a litte ... is good.... so long as all the attachments (such as controls, water and gas lines) are engineered to accomodate such movement as well.  

Think about a wash board with bumps every 6" and 5 miles long.  That's generation over 10,000 fatique cycles every time you pass on it.  This is why so many people have trailer issues going to Alaska.... 

Bottom line is that the way your Truma's were secured was not up to the job.  And that's a real problem.   How big a one is TBD.  How many trailers have this very same issue and don't have a clue about?  I for one have never checked my Suburban hot water heater's attachment.  Dittofor the 3,000 watt Renogy, the furnace, and everything else hidden below decks. 

Can I move the vertically?  If so, how much?   What's attached to that item and does it have the ability to flex enough not to become damaged.  

When doing so, I will pay a LOT of attention to anything with a gas connection first.  Hence my "Safety John" approach to this topic.

GJ

[Ollie-Haus]

1 hour ago, FloraFauna said:

Were you able to do this without removing or loosening the furnace (in the bottom of my photo and allowing very little clearance around the one side of the strap)??

I’ll send a pm regarding my fix. 

[FloraFauna]

10 hours ago, jd1923 said:

rubber bushings vs floating with only a pipe strap keeping it from bouncing down the highway!

Absolutely agree!  I would like to see rubber bushings in there and am contemplating my options to add a bit of shock/vibration absorbing/dampening.

Edited Sunday at 12:20 PM by FloraFauna
clarity

[FloraFauna]

10 hours ago, Geronimo John said:

Allowing it the ability to float a litte ... is good.... so long as all the attachments (such as controls, water and gas lines) are engineered to accomodate such movement as well.  

Exactly!  This will be my main question to OTT as well as how else is the water heater attached (as access and sight lines are difficult). 

[jd1923]

5 hours ago, FloraFauna said:

Absolutely agree!  I would like to see rubber bushings in there and am contemplating my options to add a bit of shock/vibration absorbing/dampening.

15 hours ago, Geronimo John said:

How many trailers have this very same issue and don't have a clue about?  I for one have never checked my Suburban hot water heater's attachment.

Our Suburban 6-gal HWH has a foam insulated casing and does not have hold-down straps. I'm uncertain in how it is secured besides the many screws holding the exterior plate, and the water and LP lines and electric.

Our Suburban furnace was replaced by OTT in 2020 with an Atwood model. First owner brought it in during 2018 complaining about excessive noise. When they didn't fix the noise, he brought it back in 2020, the service ticket ordered the replacement furnace.

I remembered this picture I had. It shows the furnace with the same kind of strapping holding it down to the platform below. The strapping was always a little loose and I put the section of heater hose on it years ago to add some cushion.

[Geronimo John]

17 hours ago, jd1923 said:

i understand what GJ is stating, but I’ve never received a company email re a safety warning in 3 years except the one time when they mounted a Bulldog receiver not 7K rated on one hull (was Bulldog’s fault for mis labeling their product).

OTT does react to significant issues, not with a mass mailing/email but rather  targeted ones.  What may appear to be a slow response to an issue I suspect is caused by their:

     A.  Looking into the validity of the concern

     B.  Assessing just how hazardous the concern could be.

     C.  Then doing the research of the specific owners with that specific situtation.

I too have not gotten such a notice. So I guess we are amoung large number of OTT owners that are the most lucky.  

GJ

[Snackchaser]

I remember a strap on our Truma was off because the hold holddown screw was stripped out.  However, I think Oliver probably adds the straps as belts and suspenders.   In my case, the screw was pulling the strap tight and the installer torqued it too much and stripped it.  I replaced with the next size larger screw and the tension from that screw tightened the strap like a piano wire.  I think that probably contributes to straps breaking in other installations.  

The Truma is designed to be mounted with the flange screws, so I wouldn't call it an urgent safety concern.  But it is certainly worth repairing.  

[FloraFauna]

Here is the reply from OTT tech support concerning this issue:

*********************

1) Purpose of the strap: The strap helps reduce vibration on the water heater while also locking it down into the water heater mounting bracket. It is considered an inspection item and should be inspected anytime you inspect the water heater, and should be replaced as needed.While a broken strap does not prevent the water heater from operating, we recommend replacing it, since the unit is more exposed to vibration and movement while traveling. The risk of damage goes up with rough road surfaces, uneven campsite terrain, and hard braking.

 

2) How the water heater is attached: The water heater is attached at the front of the unit through the faceplate. At the rear, it is secured through the strap, which fastens through the water heater mounting bracket and into the water heater. The strap goes over the top of the water heater to the other side and is secured the same way. There are also a few spots where the plumber's tape attaches to the water heater around its back edge.

 

*********************

 

This is helpful info.  My only beef is the fatigue failure-prone strapping is the wrong material.  @jd1923 recommended some engineered alternatives that will be more expensive but also more durable.  Now with the OTT info, I will focus on a secure vibration control. Thanks everyone for your input.

 

[Ronbrink]

Two and a half years in and found a broken metal strap securing the Dometic furnace. Replaced it and others at the Truma hot water component with cam lock straps. Strips of Marine Starboard were placed as heat protection. Great fix, here’s some pics:

Edited yesterday at 03:57 PM by Ronbrink

[Dean and Mary]

1 hour ago, Ronbrink said:

Replaced it and others at the Truma hot water component with cam lock straps. Strips of Marine Starboard were placed as heat protection. Great fix, here’s some pics:

Ron,

I think the nylon straps make a lot of sense, and that's the approach I plan to use for securing my Victron MultiPlus II after mounting it to a homemade platform. I also plan to place a section of lightweight interlocking foam floor mat beneath it to provide some cushioning and vibration isolation. It's the same material I used in my battery compartment, and it has worked well while also providing a bit of insulation. The mat may not have the heat protection that is needed for the hot water heater. One can purchase the mats at Home Depot or Lowes or ...

 

 

Edited yesterday at 05:13 PM by Dean and Mary
Clarification

[FloraFauna]

1 hour ago, Ronbrink said:

Replaced it and others at the Truma hot water component with cam lock straps.

This looks like a far better anti-vibration solution than the metal straps.

[John Dorrer]

Checked ours today and found only one strap and it was located in the center of the back of the Truma, top to bottom. It was still in tact. 

[Geronimo John]

On 11/9/2026 at 4:39 AM, FloraFauna said:

1) Purpose of the strap: The strap helps reduce vibration on the water heater while also locking it down into the water heater mounting bracket. It is considered an inspection item and should be inspected anytime you inspect the water heater, and should be replaced as needed. While a broken strap does not prevent the water heater from operating, we recommend replacing it, since the unit is more exposed to vibration and movement while traveling. The risk of damage goes up with rough road surfaces, uneven campsite terrain, and hard braking.

In a nut shell: 

     1.  "Keeps it in place especially for rough surfaces, not level areas or hard braking:"   Ok so 99% of owners are out of spec in our normal use of our trailers.

     2.  So when it breaks, we can expect to see "Movement while Traveling":   OK, so basically it is going to be moving about while traveling. And per OTT that's evidently not a life safety hazard.  

     3.  An traveling on such roads will cause "Damage" if it broken:  Damage is bad.  A broken water line while traveling is not that big of a deal unless you left the pump on.  So don't do that.  But a broken gas line is not acceptable to the vast majority of breathing owners. 

If that's their end position on this subject, I feel it is a bit short sighted from a legal, ethical, and customer service perspective.    

PS:  I really like the strapping with marine board and/or with romex.  

GJ