Truma Combi 4E Heater - Smell !

[arthur49]

Not been able to find anything same as my query using Search so...........

 

Van = Autocruise Rhythm 2010. Heater = Truma Combi 4E

 

Our last van (Adria Coachbuilt) and this one suffer from a 'burning smell' on hot water only, gas or electric.

 

I suspected a thermostat not working - dealer says there's nothing wrong - so I phoned Truma UK. They said its not a fault in heater, its not hazardous, its a heater not installed in accordance with their instructions re. warm air ducts. He spoke about the type of duct and convection etc at which point he lost me........

Solution is to swap ducts from heater around so that there is greater length on short ones before air enters the habitation area. Not easily done without a complete reinstall.

I attach a photo from which you will see two air ducts on habitation area with heater, inside bed base, within 15cm. Truma installation instructions which I've downloading specify that warm air ducts less than 50cm (mine!) should have a siphon ie a 'dip', presumably to prevent warm air entering van when heater is on hot water only.

 

Anybody similar experience?

 

Arthur

POSTING PHOTO TURNING OUT TO BE A CHALLENGE!!

[rolyk]

We had the same problem with our 6e. To save having to repeat what I said on another forum have a look here, towards the bottom of the thread. You'll also find a couple of photos.

 

http://www.autosleeper-ownersforum.com/t133-warwick-duo-modifications

 

Roly

[arthur49]

Thank you Roly. Interesting that Autosleeper also install contrary to Truma instructions. Our previous van, an Adria coachbuilt also 'smelled' on hot water, but a bigger problem on it, was the 6E heater was impossible to get at easily.

 

I've been unable to upload photo - too big - but it is permissible in 4E to block off one of the four outlets.

 

The problem is, I believe, the two overly short (15cm approx) ducts from the heater into habitation area. The third duct has a decent length on it

 

Arthur

 

 

[colin]

Timely post, I've meant to have a look at the Truma heater on our Globecar as it still smells on hot water. A WildAx we hired couple of years ago smelled so bad we stopped using the Truma water heater.

[rolyk]

Truma told me that on the 4e it is permissible, but not recommended, to blank off one of the lower ducts but the two top outlets must always be used.

 

Incidentally, our two top ducts are connected with around 650mm of ducting which may contribute to the smell, although I don't know why. You probably noticed from the photo that I had to install a bend to the left side duct as there was insufficient space to bend it. I have thought about putting one on the right side outlet too as it would take the aluminum duct liner further away from the heater although I doubt whether I'll get around to doing it!

 

When the smell starts I turn it down to the 900 watt setting as, by then, the water has reached temperature. The smell then goes away.

[arthur49]

Just checked my heater again. All four outlets are connected to ducting. Very limited space to reroute short ducts. I think I've managed to downsize photo showing two outlets into hab area and very short horizontal ducting.

 

Arthur

[colin]

Was putting new mattress's in this afternoon so took the opertunaty to access heater, which is under bed.

It is non compliant to Truma's fitting instructions (well there's a supprize, german build quality for you *-) ), of the four outlets two rise to outlets, one of which is about 300mm. I think it may be easier for me to put a downwards loop in the short pipe, might be able to get a deep dip in the longer pipe, still doesn't make it compliant but worth a go I reacon.

[tugga]

checked our heater today and I am very pleased to say that we have ducting coming out of all 4 outlets, so we should be ok. OH thinks the smell we get is the heater burning off dust that we cannot get to, looks like he is right AGAIN :-S :-S

[Derek Uzzell]

tugga - 2011-07-23 9:03 PM

 

checked our heater today and I am very pleased to say that we have ducting coming out of all 4 outlets, so we should be ok. OH thinks the smell we get is the heater burning off dust that we cannot get to, looks like he is right AGAIN :-S :-S

 

I can't find any indication in your forum postings of how old your Hymer is, so it's impossible to be certain which heater it has.

 

If your heater is a current Truma "COMBI" (as shown partially in arthur49's photo above), then your OH's diagnosis is likely to be correct.

 

If your heater is an earlier Truma C-Series (as shown partially in the photo on this link) then your OH may still be right:

 

http://www.aidecampingcar.com/forumO/printview.php?t=32663&start=0&sid=3b16f2da761f00d204297d7ccc2f3480

 

However, if you've got a Truma C-Series heater and the smell is particularly noticeably when the heater is operating in water-heating-only mode on gas, then you may have a problem.

 

There was a major safety recall of C-Series heaters a few years ago to combat internal overheating that produced unpleasant 'hot plastic' smells as a symptom. Although thousands of C-Series heaters were modified, some will undoubtedly have slipped through the net.

 

It's also the case that, while Truma only recalled C-Series heaters within a specific set of serial-number ranges, many C-Series appliances manufactured before the start of those ranges smelled when gas-heating water and there were definitely instances where the appliances overheated so severely that the heater was damaged.

 

 

[tugga]

Derek, this is scarey. I have just been and checked our handbook and it is a Trumatic C6002 EH. We have a 2006 Hymer on a 56 plate.

 

How can I check whether I am part of the re-call or not?

 

 

 

OK, I have just googled this and I have got the serial numbers and mine does fall in the category. I have also got Truma's phone number from the posting. I shall be ringing Truma on Monday morning to see what they have to say.

 

Thanks for this info Derek

[Derek Uzzell]

tugga - 2011-07-24 2:48 PM

 

Derek, this is scarey. I have just been and checked our handbook and it is a Trumatic C6002 EH. We have a 2006 Hymer on a 56 plate.

 

How can I check whether I am part of the re-call or not?

 

 

 

OK, I have just googled this and I have got the serial numbers and mine does fall in the category. I have also got Truma's phone number from the posting. I shall be ringing Truma on Monday morning to see what they have to say.

 

Thanks for this info Derek

 

Some earlier forum threads (in descending order of date) if you feel in the mood for a bit of light reading:

 

http://www.outandaboutlive.co.uk/forums/forums/thread-view.asp?tid=9576&posts=10

 

http://www.outandaboutlive.co.uk/forums/forums/thread-view.asp?tid=6959&posts=28

 

http://www.outandaboutlive.co.uk/forums/forums/thread-view.asp?tid=4470&posts=7

 

http://www.outandaboutlive.co.uk/forums/forums/thread-view.asp?tid=4724&posts=5

 

http://www.outandaboutlive.co.uk/forums/forums/thread-view.asp?tid=4532&posts=8

 

Just for the general record...

 

In my posting of 12 July 2006 on thread 4470 I wrote:

 

"Modification kit fan housing: It is clear that the two mouldings that make up the housing that carries the fan-motor must be replaced but, as the "modification kit" is not described in detail, I can't say whether it's just the original housing-mouldings that are swapped for new ones, or whether the assembly of top-cover, mouldings and fan is replaced as a complete unit. (If the latter, then there's more than a possibility that Truma may recycle parts unaffected by the safety modification, which has obvious implications for owners of these heaters.)..."

 

A conversation with a Truma technician some months ago confirmed that certain parts (eg. fan-motors) of top-cover + mouldings + fan complete assemblies removed from heaters affected by the safety recall had been recycled.

[tugga]

Hi Derek

 

Rang Truma this morning and spoke to a nice young lady call Nikki. She looked up my serial number and said that it appears that the modification does not appear to have been carried out. She asked me where we bought our motorhome and when I said Brownhills at Newark, she said that she was surprised it had not been carried out as they had the best reputation for carrying out this work.

 

She did ask me to check if there was a "Truma Checked" label on the heater or inside the wardrobe door. When I looked there is one so she felt that Brownhills had carried out the work but her database has not been updated as it was a few years old!

 

I will monitor this smell and if I am concerned further, I will ring her again and ask for the work to be re-done. I would rather pay for this modification and know that we are safe and not likely to catch fire as this is my worse fear.

 

Now I am going to read all your links. Thanks for bringing this to my attention and for your concern, I appreciate it very much.

 

 

[Brian Kirby]

I think I would be inclined to ask Truma if there is anything, apart from a label, that positively indicates that the modification has, in fact, been carried out. Error is always possible: the label may have been put in the wrong van, or have been stuck in before the work began, and then (possibly after a weekend) which vans had actually been modified become muddled, and yours never got done.

 

Failing that, challenge Brownhills with the evidence (smell, plus lack of Truma record), and ask them if they will confirm in writing that the work was actually done on your van.

 

Coupled with the smell you report, I think the missing record should be taken as indicating the work has not been carried out, rather than the label as an indicating it has. You'll be uneasy until it is resolved, one way or the other.

[Derek Uzzell]

To the best of my knowledge, it is not possible to identify via an external examination whether or not a C-Series heater was modified during the Truma recall exercise. The alterations comprised a warm-air housing made from a more heat-resistant plastic material (but otherwise visually indistinguishable from the original housing), plus an additional metal U-bracket fitted to the interior edge of the housing where it meets the heater’s top cover. This U-bracket cannot be seen unless the heater’s top cover and warm-air housing assembly are first removed.

 

The recall exercise involved Truma providing the motorhome dealership that would be carrying out the modification with a box containing the appropriate repair ‘kit’. The kit was made up of a pre-assembled top cover, warm-air housing and blown-air fan-unit (with the latter varying according to whether the C-Series heater was a C-4002/C-6002 variant or a C-3402 variant), a “Truma Checked” label, and some ‘red dot’ labels.

 

The modification was simple enough in principle – remove the original top cover, warm-air housing and blown-air fan-unit assembly, replace with the assembly provided in the repair kit, affix the “Truma Checked” label to the heater below its data-plate, affix 2 red-dot labels to the warm-air housing of the original top cover, warm-air housing and blown-air fan-unit assembly and send this assembly back to Truma in the box in which the repair kit came.

 

Although there SHOULD logically have been a ‘paper-trail’ accompanying this exercise, I’ve some doubts about its reliability. Many (possibly most, perhaps all) of the C-Series appliances that the recall covered were within Truma’s 24-months warranty period and Truma – to compensate for the hassle that the exercise caused heater owners – extended that warranty by 6 months. Having heard nothing about this from Truma after several post-modification weeks had passed I contacted Truma(UK) myself. From what I recall they were unaware that the modification work had been carried out on my heater. I supplied them with the necessary details and subsequently received a warranty extension certificate. So I’m not particularly surprised that Truma’s database seems to be incomplete.

 

I’m not sure if my heater carries a “Truma Checked” label. It’s not something that concerns me because a) I was present when the modification work was performed and b) the modification cured the heater’s previous smelly behaviour. Unlike Brian, I would take the presence of this label in tugga’s Hymer as a strong indicator that the recall modification work was done.

 

As her motorhome is 2006-vintage, it’s likely that the work would have been carried out around then (my own heater was modified in September 2006 when the Truma recall was in full swing). On that basis, I’m assuming that she has not owned the vehicle from new or she (probably) would have been aware of this work having been performed.

 

Truma’s recall instructions advise that “Units with label “Truma Checked” have been modified in the factory” (which I take to mean that some heaters with serial numbers within the specified recall ranges were modified before being supplied to motorhome converters) and there’s also the possibility that Brownhills may have modified tugga’s Hymer’s heater before the vehicle was sold to its first owner. As there’s no space on the “Truma Checked” label to indicate the date of modification and the recall was some five years ago, the chances are minimal that Brownhills will be able to confirm that the modification has been made.

 

So on to THE SMELL…

 

Truma’s Operating Instructions for a C-6002EH heater say:

 

“During the initial operation of a brand new appliance (or after it has not been used for some time), a slight amount of fumes and smell may be noticed for a short while. It is a good idea to heat the device up several times in mixed/summer operation (60°C) and to make sure that the area is well ventilated.”

 

If you’ve got a domestic wood-burning stove, or a domestic gas or electric fire, then you’ll be aware that, if it hasn’t been used for a while, there’s likely to be a smell as the stove/fire heats up and dust burns off. Truma C-Series heaters act similarly.

 

My motorhome hibernates from November through February and, when I fire up its C-6002EH heater in March, there is a mild ‘burning dust’ smell. The smell doesn’t last long and isn’t particularly offensive. Basically, it smells like dust burning because that’s exactly what’s happening! Tugga’ 23 July posting said “OH thinks the smell we get is the heater burning off dust that we cannot get to”. As I suggested in my 24 July follow-up, this diagnosis may well be correct.

 

However, THE SMELL that a ‘pre-modification’ C-6002EH heater may produce differs radically from the ‘burning dust’ smell. It occurs when the heater is operating in water-heating-only mode on gas (called “Summer Mode (hot water only)” in Truma’s Operating Instructions) and it doesn’t get better over time.

 

A C-6002EH heater in ‘Summer Mode” using gas-only and the 40°C water-temperature setting will take 25-30 minutes to raise the water temperature to 40°C, at which point the heater’s 40°C thermostat will shut the heater down. My own experience is that THE SMELL will begin to be noticed towards the end of that heating period. It’s a nasty, acrid, invasive, pungent, ‘melting plastic’ odour that smells nothing like burning dust, and it will occur every time the heater is operated in Summer Mode on gas-only. Choosing Summer Mode and the 60°C water-heating setting will add 10-15 minutes to the 25-30 minutes 40°C-setting’s heating duration and, if the heater produces a not-intolerable version of THE SMELL at 40°C, it will do it with a vengeance in the later part of the 60°C water-heating cycle.

 

Summer 2011 MMM magazine’s “Interchange” section (Page 188) includes a piece headed “RAPIDO SMELL?” Although the motorhome details (2008 Rapido 787F) suggest that this vehicle might be expected to have a current Truma “COMBI” appliance, the owner’s comments

 

“…When the water is heated on gas there is a horrible smell. Using the 60 degree setting is impossible because the smell is too bad, but all is okay when using electricity. The dealer said the smell would go away with use when bought new, alas this has not happened…”

 

perfectly describe the symptoms of an unmodified Truma C-6002EH where the plastic material of the heater’s warm-air housing is producing a noxious smell as a result of heat-soak during Summer Mode gas-operation.

 

Essentially then, if tugga’s C-6002EH heater just emits a ‘dust burning’ smell after the heater has not been used for a while, and the smell stops being produced after the heater has begun to be used regularly, then all’s well and it’s fair to assume that the “Truma Checked” label indicates that her heater has a full complement of modified parts.

 

But if her heater is regularly producing an unpleasant ‘melting plastic’ smell when in Summer Mode on gas, then this needs addressing.

 

I think there’s little likelihood of an unmodified C-Series heater actually catching fire, though instances of the warm-air housing’s plastic material being damaged by over-heating have undoubtedly occurred. My own C-6002EH heater, although it produced THE SMELL, showed no signs of over-heating damage when I examined the top cover, warm-air housing and blown-air fan-unit assembly that had been removed. I remember asking the technician who was carrying out the modification to my heater whether he had seen evidence of damage on any of the other appliances he had modified under the Truma recall and he said not.

[Brian Kirby]

Then I agree. The approach outlined by Derek is the best that can reasonably be achieved, aided by his highly informative description of the process, and of the smell.

 

In fact, we have had two of the C series heaters (neither requiring modification: in different vans) and both smell when heating water to 60C. It is not an offencive smell. Make of this what you will, but I used to work near Peek Frean's biscuit factory in Southwark, and it has always vaguely reminded me of the smell from that. As stated, this smell goes off once the heater has been used a couple of times.

[john.mcnamee]

Did you ever sort this? I've just posted a similar problem, this afternoon (3 pm 8th March 2012).

 

truma had suggested extending the pipe lengths, which I did - to 2.5m shortest. Still smells!

[arthur49]

john.mcnamee - 2012-03-08 3:54 PM

 

Did you ever sort this? I've just posted a similar problem, this afternoon (3 pm 8th March 2012).

 

truma had suggested extending the pipe lengths, which I did - to 2.5m shortest. Still smells!

 

As far as my 4E is concerned there is no change......still smells on hot water only. The van has just had the hab service carried out by a mobile Approved Workshop - he's also Truma trained. He witnessed the smell, did a bit of tinkering around, had a long conversation with Truma Technical in my presence, and both came to conclusion it was nothing to worry about..............if it had been installed with correct duct lengths and with 'siphons' where required, then stink would not exist! Something to do with type of exhaust duct and fan.......at which point I got lost...... 8-)

 

Arthur