Any Truma heating experts here?

[DL42846]

I have a 2011 Bavaria MH which has a Truma Combi system. I haven't had to use the heating system in anger so I thought I would give it a try this evening. Its about -1c out there this evening. There is no water in the system as I drained it down a couple of weeks ago but I have read you can run the heating without water in the system.
I have set the temperature to max ( 5 ) and ran it for an hour and a half. Vapor was coming out the vent out side and all the appropriate noises where going on like the fan turning etc. However the temperature of the air coming out of the habitation vets inside the MH can only be described as lukewarm and after an hour and a half the MH was still freezing. When I turned the temperature control down normally when the van has reached a certain temperature the orange light would go out to signify the van has reached that temperature setting. However after an hour and a half I could turn the temp right down to number one and the heating was still running, obviously the van hadn't even reach the minimum temperature inside.
I have had the van since March and don't know if the Truma system should be serviced or something.
Any suggestion or pointers would be appreciated. I was hoping to go away in it next week but obviously can't with such a lousy heating system.
In

our previous MH would could never run the heating system on max, it was too hot.

 

[Burgo]

Ours has a bit of a funny five minutes every so often. We usually get it back in line by turning off, waiting a few minutes, then trying again. Sometimes takes a couple of goes before it sorts itself out.
Bare in mind that (I think) on that setting it gives priority to the water and doesn't kick in the hot air full pelt until the waters up to temperature (stand to be corrected as the manual is not that clearly written on that topic as it has a strange indenting / paragraphing due the electric option). ).
Only other thing I can suggest is to make sure that if it's really cold you're using propane and not butane.
Good luck!

 

[MikeD]

I am not a Truma expert and I don't know the control system in the photo.

But if you are running just on Electric hook up the Truma will only run on about two kilowatts of heat. I doubt at -1c that would keep the van warm.

You need the gas on as well to get the full heater power.

Once running on gas the fan should blow a lot harder as well.

 

[rb62]

No expert but I think you've set the dial to heat the water as well,setting 'n' gas symbol and 60 for water so it won't blow hot until the water is at 60 which it will never be as their isn't any.Should be just on 'm'

 

[TerryL]

Are you running the system on gas or electric? The electric on it's own is actually not that powerful, without looking it up I believe its 1500 kw, and in current temperatures will struggle to reach anything like a comfortable level. Try it on gas (3000+kw) alone, it shouldn't be a problem with no water in the system, and see if that's any better. Clue to me was the orange light which on my van shows the electric heating system is in use. No orange light when on gas. We've found that once the van has warmed up the electric usually keeps it warm.

Also just spotted the dial setting - change it to heat only (anti-clock one click, the flame symbol).

You'll still need to make sure any cover on the gas vent is taken off - you have taken it off haven't you?

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[DL42846]

I am not a Truma expert and I don't know the control system in the photo.

But if you are running just on Electric hook up the Truma will only run on about two kilowatts of heat. I doubt at -1c that would keep the van warm.

You need the gas on as well to get the full heater power.

Once running on gas the fan should blow a lot harder as well.

I had the gas on. I don't think my system runs without gas even when on EHU. I have tried to disconnect the EHU and run just on gas, doesn't seem to make any difference.
Think I'm going to have to take it in and get it checked over.

 

[DL42846]

No expert but I think you've set the dial to heat the water as well,setting 'n' gas symbol and 60 for water so it won't blow hot until the water is at 60 which it will never be as their isn't any.Should be just on 'm'

View attachment 273657

rb62, your more of an expert than you think. Great, many thanks for the instructions. I have made a copy and yes it does appear I was running on winter water and heating. I have switched to the correct setting. I will now wait and see if it makes any difference. I do appreciate the effort you have made. Once again, many thanks.

 

[DL42846]

Are you running the system on gas or electric? The electric on it's own is actually not that powerful, without looking it up I believe its 1500 kw, and in current temperatures will struggle to reach anything like a comfortable level. Try it on gas (3000+kw) alone, it shouldn't be a problem with no water in the system, and see if that's any better. Clue to me was the orange light which on my van shows the electric heating system is in use. No orange light when on gas. We've found that once the van has warmed up the electric usually keeps it warm.

Also just spotted the dial setting - change it to heat only (anti-clock one click, the flame symbol).

You'll still need to make sure any cover on the gas vent is taken off - you have taken it off haven't you?

Terryl, Many thanks for the info. I didn't know how or if my system works on just electric when on EHU. Now its all starting to make sense. I'm not sure what you mean by "You'll still need to make sure any cover on the gas vent is taken off - you have taken it off haven't you?" Is that the vent outside the van on the side that gives of steam or vapor when the system is running. I don't know of any cover on it.
Once again many thanks for your help, very much appreciated. I'm beginning to get somewhere now.

 

[Just smiffy]

Ive unknowingly answered your question on your other posting without knowing of this double post....

I have the same system, it does not run on electric.... only gas....

 

[Landy Andy]

You have control set to the wrong setting, as so it is trying to heat a dry water cylinder as you have drained it. You won’t get much heat whilst in this setting as the system always prioritises hot water over heating. But it can’t get the water up to temp, because you’ve drained it.


Andy

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[TerryL]

Terryl, I'm not sure what you mean by "You'll still need to make sure any cover on the gas vent is taken off - you have taken it off haven't you?" Is that the vent outside the van on the side that gives of steam or vapor when the system is running. I don't know of any cover on it.
Once again many thanks for your help, very much appreciated. I'm beginning to get somewhere now.

Yes, but they don't all have them, yours obviously not. If you've got "steam" coming out it's clear.

 

[Ingwe]

What Andy says and the poster who pointed out to move the dial one click anti clockwise.

 

[Tude]

You can only run the system without water on gas and also not heating your water.your setting is for hot water and heating. Put your setting just on the flame which is heating only.

 

[dave newell]

You can only run the system without water on gas and also not heating your water.your setting is for hot water and heating. Put your setting just on the flame which is heating only.

you can run a truma combi on gas, electric or both either with or without water. The electric elements are embedded in the aluminium heat exchanger, not directly in the water tank so they will not burn out if used without water.

D.

 

[DL42846]

Well, I have tried it with the heating control set to heat with no water in the system and part filled the system and tried it for heating and hot water and still the heating system does not warm the MH up. I had it running for an hour this morning. The thermostat control doesn't appear to be doing anything. So it looks like our New Years eve trip is canceled and it will go in for repair when my guy comes back from his Christmas holidays. I suppose I'm going to be painting and decorating instead.

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[Just smiffy]

Hmmm, have you had a look at the system, as in the pipe work to make sure it’s all ok ie: not blocked or kinked or a mouse nest ...?

If you’ve got steam coming out of the vent it must be getting hot in the boiler.... when you tried it with water was the water very hot coming out of the tap..?

Does the air blow out of the vents quite good whether the air is hot or not..?

It sounds like something simple as the boiler looks like it’s working ok....

 

[DL42846]

Hi everyone, many thanks for all your constructive comments and all the suggestions which was offered. I thought I would let you know what's happen so far.
This morning I took it down to our local MH repair center. He immediately changed the temperature heat censor inside the MH. He had a load is stock and said they often go and are the source of a lot of problems. However no difference. He carried out a few checks on the system and contacted Truma and got a few pointers. What seems to be happening is the Truma system starts up and everything is fine but it doesn't go into the second stage of operation which is where the fan starts and blows the hot air into the MH. What I am getting is only the start up heat not the second stage.
Unfortunately he does't have the diagnostic computer to check the electronic card system. The other garage that does is closed till the 3rd Jan, so I will have to wait till then.
For those interested I will keep you posted for future reference.

 

[Gellyneck]

What model is your Trumi system?
If it's a 4E \ 6E does it have a circuit board under a cover on the long side of the heater \ boiler?
If so, is it flashing a series of coded flashes, long \ short. If it is that can give you pointers to where the fault lies.
We had a similar problem (though not exactly the same) and this code identified a couple of potential part faults, in our case a problem with the air circulation fan \ motor (from memory).
We were heck of a lucky in that it was the fan well clogged up with muck \ hair from the dog (the filter \ cover to it hadn't been fitted properly and had fallen off!) and after cleaning it out all was well.
If it ain't that model sorry for wasting your time reading this drivel.

 

[DL42846]

What model is your Trumi system?
If it's a 4E \ 6E does it have a circuit board under a cover on the long side of the heater \ boiler?
If so, is it flashing a series of coded flashes, long \ short. If it is that can give you pointers to where the fault lies.
We had a similar problem (though not exactly the same) and this code identified a couple of potential part faults, in our case a problem with the air circulation fan \ motor (from memory).
We were heck of a lucky in that it was the fan well clogged up with muck \ hair from the dog (the filter \ cover to it hadn't been fitted properly and had fallen off!) and after cleaning it out all was well.
If it ain't that model sorry for wasting your time reading this drivel.

Thanks, i will check that out. Always interested in receiving suggestions as it may come in handy later

 

[TerryL]

Your comment about the second stage not working rang a bell. On our first ever rally to a show (Peterborough I think) the second day the heating failed to come on. The so-called Truma agent said he didn't have the parts despite not even looking at it. Dave Newell had a stand there and I went and asked - he came straight over to the van, put his hand down the side of the boiler and said some sort of actuating rod was loose and not allowing the second stage to operate. I produced a nut which I had found when having a quick investigate myself - that's the jobbie, he screwed it back on, borrowed a pair of pliers to tighten it, all done in less than five minutes and no further problems ever since! I'm not exactly sure just where this part is but my experience might give you a clue.

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[Just smiffy]

Your comment about the second stage not working rang a bell. On our first ever rally to a show (Peterborough I think) the second day the heating failed to come on. The so-called Truma agent said he didn't have the parts despite not even looking at it. Dave Newell had a stand there and I went and asked - he came straight over to the van, put his hand down the side of the boiler and said some sort of actuating rod was loose and not allowing the second stage to operate. I produced a nut which I had found when having a quick investigate myself - that's the jobbie, he screwed it back on, borrowed a pair of pliers to tighten it, all done in less than five minutes and no further problems ever since! I'm not exactly sure just where this part is but my experience might give you a clue.

Perhaps @dave newell lvs might remember ..?

 

[dave newell]

Yes I do remember. Terry's problem was the actuating coil for the second stage gas valve had come adrift due to said nut falling off. The big difference is that terrys is a c series unit rather than a combi. Although it could still be a similar issue I doubt it. I have recently fixed a combination that fired up ok but produced very little heat from the outlets, that turned out to be the main PCB, specifically the section that controls the distribution fan meaning the fan was barely running to distribute the hot air.

D.

 

[DL42846]

Yes I do remember. Terry's problem was the actuating coil for the second stage gas valve had come adrift due to said nut falling off. The big difference is that terrys is a c series unit rather than a combi. Although it could still be a similar issue I doubt it. I have recently fixed a combination that fired up ok but produced very little heat from the outlets, that turned out to be the main PCB, specifically the section that controls the distribution fan meaning the fan was barely running to distribute the hot air.

D.

Hi, this seems to be the problem with mine. I have checked as someone suggested the first fan on the boiler. It was clear, a little dusty which I cleaned off. The second fan which is in a separate unit is turning but no real force. I did try putting my hand around and tried to feel if there were any connections going to it but couldn't feel or see any, even with the use of a mirror as its difficult to get to it. All these suggestions are great as they are helping me to get to know my Truma. I am coming to the conclusion that it might be something on the electronic card in the system which might be the problem as suggested by my repair guy. Unfortunately he doesn't have the diagnostic kit to test but has suggested someone , but they are closed until the 3rd January.

 

[DL42846]

Up date:
I took my problem to a MH repair center. He connected the truma up to a diagnostic pc. Everything seem to be functioning as it should be. After a couple of calls to Truma he claims my 4KW truma is not up to the job for the size of my MH. He recons I should have a 6KW. I have 9 vent outlets in the van. When he closed a couple of them off The pc showed the temp of the Truma was 103c when all the vents were open it dropped down to 100c and the hot air was reduced to a trickle.
What I am now considering is getting a diesel heater fitted. I have seen some on eBay going for as little as £140 for a 5kw heater or £150 for a 8kw. These are supposedly guaranteed for 10 years. I did look at the Eberspatcher ones but they are considerably more. Has anyone had any experience of these?