Truma Combi Water heater/Furnace

We ordered the Truma Combi water heater/furnace with our new PC and was wondering if anyone else has this system. This system has been used in Europe for quite a while with mixed reviews, lots of good and lots of bad. Is it as quiet as advertised? when valve is positioned to maximum hot water does it give enough for showers because it says it only holds 2.5 gal of hot water. Also when used for head does it do a sufficient job of keeping PC warm.  Thanks

I think you are paving a new road in PC country.  I never heard anyone on this forum (or other RV forums) discussing that system before.

Read this first... No idea if it applies to Phoenix...

https://www.truma.net/combi-buying-advisory

I have no personal knowledge or experience with the Truma Combi system, but I don't believe the issue noted in Don's attachment applies in the Phoenix applications.  I note that the Truma message that Don linked includes the following sentence:  "We work closely with our manufacturing partners to ensure a safe and reliable installation of our equipment......".

The very first application of a Truma Combi in a PC was when Phoenix was developing the "new" 2351D a little over a year ago.  I happened to be at the factory and looked over the 2351D prototype being built--and talked with the Phoenix engineer working out the issues for the new model.  Phoenix couldn't use their regular under-bed furnace in the prototype since the bed was now in a slide that moved--so after looking at alternatives they decided to go with the Truma Combi unit placed where the normal hot water heater would usually be for both hot water and heating.  The engineer told me that they were getting good support from Truma, and the Truma reps actually came to Phoenix and worked with him to sort out the new application and make sure the finished installation worked well.

Since then Phoenix has incorporated the Combi as an option in other models--but I'm quite confident that Phoenix has maintained that direct relationship with Truma that ensures reliable repair and warranty support.

Mike

I also found that warning, and it DOES apply for USA.  Mike is correct, the units installed by PC are going to be supported, as they are properly sold to a dealer, that then sells to the end user (the purchaser of the camper).

The units they are warning about are 'in the wild'  from Erwin Hymer Group North America going belly up, and its assets being sold, including some Truma products.  This sold inventory is now circulating and evidently being sold outside the Truma approved system.

So should you see one of these units available on Ebay, Craigslist, or other private vendor, you are on your own. They (Truma) undoubtedly have a method for ID'ing the units that were sold as excess inventory.  Does not matter if you legally bought it from someone who legally bought it. Truma got their $$ already, and since they can get out of supporting the product, they will!

Way to support your product. I am wary already on buying anything with the Truma name now! I now call  them Trauma. 

 ""We work closely with our manufacturing partners to ensure a safe and reliable installation of our equipment and therefore do not allow unauthorized sales, installation or repair of our Truma systems. Safety is critical to Truma and these systems require compliance to specific international standards.""

So be advised that if there is any problems down the road with this unit, you are NOT allowed to fix it yourself. Parts will not be available to you. You are to `ONLY go back to the original supplier or authorized repair shop.  And if you bought from the sell-off stock....you are SOL. 

Like my opinion matters to anyone, but this unit looks like a sh*tstorm of complication to me. Sure it packs both units into a small package allowing manufacturers to create new layouts. I am sure there are many, many safety measures in place which will never allow disasters.     What could go wrong combining fire, water and forced air for ventilation?  Cold night with no hot water is my guess. At best. And dont think you will have a necessary part 'express delivered' to your camp....you WILL go where they tell you to get it fixed. Try to avoid camping in areas not local to a Truma service center for best product experience.

Guess I am gonna go back and yell at the kids on my lawn.      https://www.youtube.com/watch?v=Ltexj_2UTQo

So the Truma Combi is standard equipment in model 2351D.

It seems feasible if special-ordering model 2351D without a front slide out, the rig could avoid a Truma Combi system if Phoenix configured it the same as our no-slide 2350.  Our furnace is located under our fridge with 3 short-run unobtrusive heating ducts on the driver side.  I always felt our heating system was setup nicely with the furnace and ducts NOT taking up critical storage space.

Trade-offs, trade-offs, it's all about trade-offs.

Like my opinion matters to anyone, but this unit looks like a sh*tstorm of complication to me. Sure it packs both units into a small package allowing manufacturers to create new layouts. I am sure there are many, many safety measures in place which will never allow disasters.     What could go wrong combining fire, water and forced air for ventilation?  Cold night with no hot water is my guess. At best. And dont think you will have a necessary part 'express delivered' to your camp....you WILL go where they tell you to get it fixed. Try to avoid camping in areas not local to a Truma service center for best product experience.

Atwood H/W Analog Truma Digital..pretty complicated set up.

I took a look at the two of the other forums I belong to on Facebook.  One using the Atwood had 4 mentions of issues in 38 months, 1800 members.  The one using the Truma 12 issues in 22 months, 1700 members.

I understand when they work, they are very nice....but

We have what I suppose is one of the first 2351D with the Truma Combi Eco Plus (It has gas plus electric heating elements.). On the air side it’s great.  Very quiet, very fuel efficient and plenty of heating capacity.  On the water side, after taking three cold showers I’m still trying to get the settings right.  It has three temperature settings, eco 104 degrees, hot 140 degrees, and boost 144 degrees and several gas/electric combination settings.  So far I’ve tried the hot setting and quickly ran out of hot water, even trying to be very conservative with the water.  The shower head from PC doesn’t include a shutoff valve so I added one.  I’ve read mixed messages about boost.  One source said it’s purpose is to heat the water faster, the other said it’s for showers - which probably makes sense, since recovery should be much faster.  The operating manual gives no information on the various water settings. 

My next shower will be with it set on boost along with waiting about an hour after setting it.   Hopefully that will provide enough capacity for a reasonable shower.  Otherwise, the Combi is going to be a disappointment.

Just a little FYI...  I took a shower with the Truma Combi on the boost setting and “mix 2”, which means gas + 1700 watts of heating elements.  Waited an hour after setting it to boost.  Had just barely enough hot water even with shutting the water off while washing.  Our previous coach had an on demand water heater and spoiled us with unlimited hot water.  I was hoping the Truma Combi had a fast enough recovery to do the same, but it doesn’t look like it can.

Grandpa17: You are making me feel like maybe I "dodged a bullet" as we had seriously considered that option for our 2552  but in the end decided to stay with the tried and true.
The technology seemed too new and I couldn't find a simple GPH (gallons per hour) spec on them. The rep at the Tampa show couldn't give me one!

Hopefully they will be able to identify an issue with your Truma that will  make it right for you.

In the mean time maybe you should consider a flow restrictor type shower head to limit the throughput during your showers?

Good luck!

Yea, information on how to best use the unit is sketchy.  What I’ve found is to set it on boost and wait about a half hour and take your shower right away.  All the manual says is that on boost it will do “two cycles” but gives no explanation of what a “cycle” is.  After the two cycles (can’t tell exactly when they are finished) it reverts back to whatever it was set on before setting it to boost.  So if you go from off to boost, it will return to off.  If you wait too long, the water starts cooling off and you won’t have near enough hot water for a shower.  Now that I have it at least partially figured out it’s been working well with enough hot water for a good shower.  I do restrict the flow also.  My preference for sure would be an on/demand heater but I was told there wasn’t room to fit a furnace and water heater into the 2351D floor plan.