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Truma boiler problem -all or nothing


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I wonder if anyone can help out on this one. I have an Autotrail Cheyenne with a Truma C 6002 EH combi boiler. The problem is - when I turn on the power unit for the whole of the motorhome the warm air central heating fan comes on instantly, even with the control panel dial set in the 3 o'clock 'off' position - and before I get chance to set the rotary switch to the desired heat setting. To minimise the chance of a flat battery, I've turned down the thermostat to 1 - the fan stops and the boiler doesn't fire up - but this isn't the way to cure the problem. Any ideas please? Thanks - Steve in Preston
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Welcome to the Out&AboutLive forums, Steve.


Your Cheyenne has a Truma C-6002EH (which was superceded by the "Combi" range in mid-2007) so it's plainly a few years old.


As you'll be aware, a C-6002EH heater has two control-switches - 'Switch A' selects the 'power' (gas, 230V or 230V+gas) to be used: 'Switch B' allows heating of air, water, or air+water (and 'room temperature') to be chosen.


It may be necessary to operate the main 12V switch on a motorhome's control-panel to allow the heater to operate (that's the case with my Hobby's C-6002EH) but, while the heater's Switch B remains in the 3-o'clock OFF position, the heater should do nothing.


Based on your description, it would be logical to think the problem lies with Switch B - that, although the switch is in the OFF position, the switch is not actually turning off the heater (perhaps due to the switch having worn or to a broken internal part within the switch) and the heater 'believes' blown-air heating has been chosen. What happens when you select water-heating only - does the heater's air-circulation fan stop running then? (Presumably your Cheyenne's heater hasn't always done this?)


If your heater is otherwise operating normally, I can't think of any other reason for what's happening, but the only way to test easily whether Switch B is the the culprit may be to replace it with a switch that's known to work OK.


I suggest you phone/e-mail the Truma(UK) technicians to see if they have an explanation





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Greetings Derek! Thanks for your quick reply and all the information. I rang Truma this morning but I have to say they weren't too helpful.According to them it's either the PCB ,the control switch B or the fan itself. The answer - take it to a dealer.However, I am going to go through your suggestions first and see if I can resolve it myself. I'm delighted with your assistance. Thankyou. Steve from Preston.
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As, when you turn the 'room temperature' dial down to its minimum "1" setting, you can stop the circulation-fan running and the heater won't attempt to fire-up on gas (and presumably the circulation-fan would begin to run and the heater attempt to fire-up on gas if you then turned the dial to a high setting) I believe the fan-unit can be discounted. The fan-motor just has a couple of wires leading to it for 12V power, so there's not a lot to go wrong there.


I think the control-panel ('Switch B') is common to C-6002 and C-6002EH and seems to be available for around £60. Better hope the fault's not PCB-related as that's £300+.


The reason I asked about trying the appliance on water-heating-only was just in case there was something blindingly simple like the switch's dial having 'jumped' a notch so that a water-heating setting had become the Off position.


If you don't get any joy fiddling about with the switch, you might try removing it and unplugging/replugging the wiring-harness from where it connects to the switch's rear.


It's about 90 miles from Preston to Truma(HQ)'s place near Derby. Might be worth you arranging to visit them there if the problem persists.

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Good morning Derek! You are a gem. Thanks for your latest piece of advice. I've not followed everything up yet but I've completely disconnected the 'control panel' with the faulty 3 'oclock 'off' switch and the contacts behind, in the hope that your suggestion that the switch might have jumped down a notch could be true. Then I turned on the power to the motorhome - but the fan still continued to whirr round, even with the control panel removed from the equation.


If I'm not wrong, wouldn't this suggest that the fault lies somewhere before it reaches the control panel and is either in the PCB or the fan itself? Regarding, taking it elsewhere, I rang up all the dealers around Preston before and after the New Year - Todd's, Campbell's, Marquis etc and they're all booked up, which rather surprised me. This wouldn't be so bad if we weren't going to the Alps at the end of the month - thus the urgent quest to get the heating system repaired. I'm delighted that you've taken an interest - thank you so much. I'm going to look at the rest of your ideas today. Thanks again. Steve from up North.


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As I understand the situation, your heater is acting as one would expect it should when switched ON at the control-panel (Switch B) - except it's doing this when Switch B is in the OFF position.


I don't think there's a problem with the circulation-fan unit as such because you are able to stop the fan running by turning down the room-temperature setting. There's also the fact that, besides the circulation-fan starting to run when you turn on the habitation 12V power, the heater commences its gas ignition procedure.


(I'm assuming that, when you turn on the habitation 12V power, the green LED on Switch B illuminates and, if you didn't turn down the room-temperature setting to "1", the heater would fire up on gas and provide blown-air heating.)


I would have thought Switch B is 'dumb' and all the clever stuff goes on at the PCB. I wouldn't have expected the heater to run with Switch B disconnected (and I'm not going to disconnect my C-6002H's Switch B to check what my heater does ;-) ) That your heater's behaviour doesn't change despite Switch B being disconnected suggests the problem is at the heater end.


When you turn on habitation 12V power it's plain that the heater's power supply becomes 'live' (which is what one would anticipate unless the heater had been separately cabled). At that point, I don't know if the heater would run unless Switch B is in the OFF position (ie. running is the default) or whether moving Switch B from the OFF position is needed to start the heater running (ie. not-running is the default). I would have thought the latter but - other than knowing that the PCB has a lot of components on it and ain't cheap - I'm unfamiliar with its intricacies.




Even if you took your Cheyenne to a motorhome dealership, unless the dealership could correctly diagnose the reason for the problem and it was easy to correct, there'd likely be a need to obtain spares. Logically, one would replace Switch B to see if that provided a cure and, if that didn't work (as it doesn't seem to in your case), the next step would be to replace the PCB. I'm not sure that a motorhome dealership would be in a position to do that immediately but Truma(UK) certainly should be.


As long as your heater is accessible, PCB replacement should be straightforward and quick. Truma(UK) might be able to fit you into their schedule if you can assure the technicians that no preparatory effort (like dismantling half your motorhome's furniture) will be required before the heater can be worked on. As you've got an Alpine deadline, I suggest you try to book an appointment with Truma(UK) ASAP as I think they are your best bet.


I don't believe it's relevant to your problem, but it's perhaps worth mentioning that quite a few C-6002EH heaters were involved in a safety-modification programme some years ago. Details are in my posting of 27 November 2013 1:44 PM on this earlier forum thread:



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One follow-up thought...


If you can get at the PCB easily, you could try unplugging then reconnecting all the cabling that connects to it just in case the plugs have somehow loosened or there's a dodgy connection. Can't say I'm optimistic that this would do anything miraculous, but it would be worth a try.


(If you do this, make sure you switch off the habitation 12V power first.)

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Guest Had Enough

I had a hugely irritating intermittent problem with the heater in my Hobby. A Truma authorised agent was baffled and in the end I mad an appointment with Truma at their Derbyshire HO.


They couldn't have been more helpful. They solved the problem after two hours of testing but only charged me for an hour's labour and some small parts. They've a nice canteen that you can wait in whilst the work is being done.


When installing my system the wire connecting the control panel in the habitation unit to the heater in the garage was routed behind a pull-out drawer. The wire hadn't been secured properly and had come loose. This was a drawer we seldom used but every time we opened and closed it the wire was compressed and the connection was lost.


Truma meticulously started testing the Combi heater and when they found no fault tested the control panel and also found no fault. They then traced the cable and discovered the problem, which was repaired and it's been OK since.


They will make an appointment but I had to wait two weeks as they were busy, so if you do want to go to Derbyshire you need to be getting in quickly.



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Hello again Derek!

First, let me say how knocked out I am by your assistance and how much of a better understanding you have of Truma central heating boilers than I. I think you've 'got it' in terms of the pictures you've managed to convey to me of the control panel and switch B, the 'off switch' in relation to the central heating setting and why it's probably not a fault relating to the fan. You're also right in that the green light comes when I turn the rotary switch to the heat setting, followed fairly quickly by the red light, because the system hasn't fired up while the thermostat is turned down to 1.


I didn't want to spoil the progress by turning up the thermostat to see if the boiler fired yesterday because I was called upon to do other things but I'll live in hopes and do this in a day or two back on the compound where the motorhome lives for most of the year. I'm beginning to wonder - if I don't have time to get booked in and seen by Truma before I set off for the Alps - maybe I can forget about the designated 'off' switch completely and control the heating while I'm away by choosing the heat setting and moving the thermostat control from 1 to the required number to get the bolier to fire - then turning it down again to 1 to switch it off. Does this sound feasible as a stand by if all else fails?


Short of all this, I could also disconnect the contacts on the PCB - then replace them and see if itall works again, by magic, or by way of a revitalised dodgy connection. Either way, I'm delighted by your input. Thanks for all your time and effort. I'll let you know how it goes shortly.

Steve up North.


Brian - thanks for your thoughts on my predicament. You're right in that I should go to the manaufacturer of the product to get a definitive resolution but, if they can't fit me in for a week or two, it might be better to risk it in the Alps - then go to them on my return. I've also had additional thoughts on supplementary heating while I'm away - fan and oil heaters if Im on a site - a small gas appliance in the wild (not forgetting the rules on the dangers of carbon monoxide) I also have a small portable generator but it's never been out of its box - not sure I'd know what to do anyway, having heard so many confusing reports. Thanks again!



Had enough - Thank you too for your suggestion. I didn't realise just how helpful people could be in the caravan/motorhome fraternity. I'd be willing to drive down to Derbyshire to Truma HQ, just as long as it wasn't a day before I was setting off - then had to drive back north to Lancs - then set off south again the day after. But, you're right, I guess they're the ones who have the instruments to test out all the theories. But isn't it so frustrating to have such a problem at the very moment you decide to have a winter holiday and realise just how important it is to keep warm - it never happens in summer!



Mel B - another good idea to add to the others and one which Derek also suggested. I saw on another forum that somebody had disconnected all the connectors at the PCB - then put them all back exactly as before - and hey presto! - everything worked again. I suppose it makes sense, in the same way that you sometimes need to move batteries around in a remote control to disperse dirt and dust. I can only say 'thank you' to you and to everybody else who's given so much thought to my untimely problem. I'll clue in more often to the forum to see what's in the news. Thanks again!


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I’ve never experimented with my C-6002EH heater to see what would happen if I selected blown-air gas-fuelled operation with the room-temperature setting at minimum, or chose the minimum temperature-setting while the heater was in the start-up phase. My initial thought was that the heater would do nothing, but I’ve now decided that it might well go into fault mode (green light, then red light) as you’ve said yours does.


Will you be able to work around the problem easily while you are in the Alps? This will really depend on how many of the heater’s facilities are functioning normally and how many are not.


At present you know you’ve got a problem that affects blown-air gas-fuelled operation. Despite the heater being switched off, when you turn on your motorhome’s 12V habitation power the heater’s air-circulation fan begins to run and the heater would fire up on gas if you allowed it to do so. To deal with this situation you turn down the room-temperature setting to minimum.


A C-6002EH can run on gas, 230V or 230V+gas. It would be worth you checking what happens if you select 230V electric operation via the Power Selector Switch (without the motorhome being connected to a 230V mains power supply) to see if that prevents the fan running. If it does, it might be a better tactic (when your motorhome is not ‘hooked up’) to ensure the heater doesn’t run when you've switched on the 12V habitation electrics.


My first Truma C-Series heater (a C-3402EL) stopped working on gas on Day One of a fortnight’s holiday in a freezing-cold wet March in Brittany. This forced us to stay on campsites with 230V hook-ups and use a fan-heater for warmth. (In fact, although my C-6002EH has a 230V blown-air capability, I still prefer to use a fan-heater as it’s quieter at night.) The C-3402EL heater’s 230V water-heating feature was unaffected, but we could have survived without that capability by staying on campsites.


In your position, if Truma(UK) couldn’t look at the heater in the very near future, I’d want to try disconnecting/reconnecting the PCB (easy on my Hobby, perhaps less so on a Cheyenne). If the problem persisted, I’d want to establish what the heater did (or didn’t do) when 230V-operation was selected and/or when water-heating-only was chosen.


If the problem only affected the ‘Switch B’ On/Off function, I’d be comfortable going abroad and using your room-temperature Setting-1 ploy. If the fault proved to affect more than just the heater’s On/Off function, at least I’d then know what I would have to deal with when abroad and (as you are already doing) could decide on a strategy to work around the problem.

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It is defiantly worth an hour or so taking all the connectors off cleaning them, you never know your luck.

Connection issues do seem to be a problem with these heaters, when we first had our van for the first 18 months 2 or 3 time a year the heater would not start red fail light would come on, I took off all the connections cleaned them, it has not failed for the last 4 years.

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Hello again Derek! I'm impressed with your logic and inventiveness re the warm air central heating problem on my Autotrail Cheyenne. At present I'm in the Lake District practising a few snow and ice skills in anticipation of the Alps but I'm back later today.

I must admit, it hadn't occurred to me to try turning the power control switch from gas to electric power ro see if that maneouvre disengaged the fan on control B. It's simple enough I guess so I must be a bit dim. Anyway, I'll try it and let you know.


Apart from that, booking in at a campsite and using mains power to run a small fan heater would seem to be the best and least dangerous way of keeping warm - something you've done yourself - unless, of course, there's no camp site available, in which case I'm thrown back upon the will it/won't it work using the thermostat to control the on/off operation of the heating. I'll also test that theory out when I get back home to Preston.


It seems that quite a few caravanner/motorhome enthusiasts have discovered that disconnecting, cleaning and reconnecting contacts on the PCB has done the trick, as you suggest. In that regard, is it possible that the pcb is already wrongly wired up? If so, is there a digram showing the correct connections? I've tried to find one but haven't succeeded.


I rang Truma but it's too close to setting off time to book the motorhome in but I'm confident we'll survive the freezing alpine temperatures, one way or another. Besides, my wife, who is French, is catching a train from Geneva down to her family home in Provence after a couple of days in Chamonix, so I'm the one who's staying on in the ice box. It makes for an interesting winter holiday.


Thanks, Derek, for all the time you've taken to think this one out and for all your excellent assistance!

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northernsteve - 2014-01-17 7:28 AM


...It seems that quite a few caravanner/motorhome enthusiasts have discovered that disconnecting, cleaning and reconnecting contacts on the PCB has done the trick, as you suggest. In that regard, is it possible that the pcb is already wrongly wired up? If so, is there a diagram showing the correct connections? I've tried to find one but haven't succeeded...



I'm getting the impression that you haven't owned your Cheyenne long, otherwise you'd know whether its heater used to work differently to how it now does. That before a certain point in time the heater would remain off when the habitation 12V electrics were switched on and, after that moment, the heater would begin to run with it's On/Off switch in the Off-position.


To the best of my knowledge there are no detailed wiring diagrams for these heaters available on-line and, as faults are normally corrected by fitting replacement components, it may well be that Truma(UK) won't have diagrams either.


As will be apparent from Truma's installation instructions, the electrical connections are simple enough. Obviously there is the possibity that the wiring harness connecting the control switches to the heater might be miswired, but this should have shown up when the heater was new. Similarly, if the heater has functioned 'normally' for several years, although its wiring may now have developed a fault (as happened with Had Enough's drawer-related problem) there's no real reason to expect the wiring to have degenerated.


Unless you can think of something that was done to the vehicle (like a habitation service) after which the heater began to exhibit this odd behaviour, I don't think guesswork will identify the problem's cause. Disconnection/reconnection of the cabling at the PCB would be worth a try (As lennyhb says, you never know your luck), but if that ploy fails you'll probably need to visit Truma(UK) when you get back from your Alpine trip.





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northernsteve - 2014-01-17 7:28 AM




It seems that quite a few caravanner/motorhome enthusiasts have discovered that disconnecting, cleaning and reconnecting contacts on the PCB has done the trick, as you suggest.


Our Combi was (remotely) diagnosed as having a fault on wiring to PCB, this was from a code flashing on the PCB, it was suggested by dealer (to save a days trip to them) that I remove and replace connections on PCB, this had no effect, but as I was putting everything back together it occurred to me to remove and replace connections on control panel, this solved the problem, no 'cleaning' was involved, just a wriggle of the plug to ensure a good contact was made.

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Unfortunately, unlike your Truma "Combi", a C-6002EH heater has no flashing-LED fault-code feature to assist diagnosis.


In my posting of 13 January 2014 4:58 PM I suggested unplugging/replugging the control-panel, but Steve's experimentation revealed that the problem remained even when the control-panel was physically disconnected from its cabling. Presumably, when the control-panel was reconnected, the fault had not disappeared.


Steve's trip abroad is fast approaching and, as he has a work-around that should allow his heater to be turned off when his motorhome's habitation 12V electrics are on, it would be risky to do too much playing about with the heater in the hope that a miraculous cure would take place.


With no deadline to be concerned about I'd try unplugging all the cabling from the heater, then reconnecting each plug individually to check at what point the fault showed up. If the fault were present even when all the cabling was unplugged, at least one should then be able to discount the cabling as the culprit (though, of course, there is the possibility that unplugging all the cabling from a normally-functioning C-6002EH would cause it to behave as Steve's heater is doing!) But I'd be wary of doing extensive trouble-shooting if I were Alpine-bound a few days hence and my heater was only 'slightly broke'.

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Good day again Derek. You pick up on all the salient points - thinking along the lines of an investigator into why things fail or haven't been diagnosed before now. In that regard, it might appear that I've not had the Cheyenne for very long but I've got to admit that I've had it from new since 2006. So it's probably very remiss to have to add that the heating was fine for a couple of years - except that we never used it. 'Why?' you might ask.


Because we only ever used the motorhome for one month in each year - and then only to go to a baking hot Provence in midsummer. By then, although I realised that the heater was faulty. I'd also realised that I could control the errant fan by turning down the thermostat on Control B. In fact, I ought to have taken it for repair five years ago but, as we knew we weren't going to make use of the warm air central heating, it didn't seem necessary.


It's only now, by changing our routine and going to the Alps in winter, that the heating has become an issue of some importance. I plead guilty. On the other hand, you and others like you have been so helpful that, if I don't freeze to death in Chamonix during the month of February, it will all be down to your good works - so thank you again.


As an afterthought, I only got back from the Lakes a few hours ago but, over the weekend, I'm going to test out your theory re turning the power switch to electric to bypass the fan and also to clean up the contacts on the pcb and the control panel. I'm very grateful for your input. Thanks again. Excelsior!

Steve - up north.




Lenny hb - Thanks for your suggestion. It must have some merit because cleaning the connectors has been a very popular suggestion of several contributors to resolving this problem, so I'm going to go with it and see what happens. Thanks again!



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Steve, as I'm sure you will be aware temperatures in the Alps can go extremely low with -25C plus wind chill to be anticipated. This will place considerable demands on your heater, and also on your gas supplies. In the absence of gas your electric heating elements will do little more than take the chill off at such temperatures. So, expect to consume large quantities of gas! If your system is re-fillable that should be fine, otherwise do be prepared for the fact that French gas cylinders will not connect to UK propane pigtails, though they will connect to UK butane pigtails. Depending on how long you will be at altitude, it may pay you to get a couple of UK butane pigtails and make sure you have the tools to swap them over as required.


Depending on the size of your gas locker, you may have some difficulty finding French cylinders to fit. Most continental vans have gas lockers suitable for two 13kg cylinders, many UK vans will only take two 6kg cylinders. If this is the case, finding suitably sized cylinders, and the snap on connectors they commonly use, should, perhaps, be one of your first priorities on arriving in France.


If your water tanks (waste and fresh) are suspended below your van, you will be likely to experience freezing problems unless both are insulated and have heaters. In addition, many UK made vans have underfloor water and waste pipes that are even more prone to freeze. Do check yours before you go. You may need to travel dry (except bottled water for drinks) and use only sites with full facilities so as not to require on-board water while in sub-zero temperatures. Once frozen, 100 litres of water will take a very long time to thaw out, even with warmer temperatures. It goes without saying that frozen pipes that run externally will not thaw while temperatures remain sub-zero.


If snowy on site, remember to lift and move your electric hook-up cable daily. Otherwise, because they run slightly warm, they gradually sink into the snow and ice and become irretrievable. Then, you can't use hook-ups on the way home! :-(

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For about 20 years until we got the motorhome 4 years ago, we took a caravan to the Alps in February for skiing. We only used either a small convection heater of about 1.5Kilowatt, or a fan heater of the same sort of power.


It was toasty warm in the van & we sat in T shirts most evenings. The night temperatures were often -15 to -20C but we were fine (including my daughter from age 2 years) We only used the convection heater on a low setting at night, but did have 2 duvets, one under one over. We also had a back up fan heater in addition to the two mentioned above (Just in case!) We too made sure the EHU cable was suspended above the ground as Brian advises.


Even now with the motorhome we still take a couple of fan heaters with us - they are light and we always stay on sites with EHU so why use gas?


Just a thought if you can get to the wiring of the fan, as a temporary measure could you not put a simple car type switch on it so you can effectively isolate the fan? It would mean you'd have to cut a cable, not a great problem, but it might just get you out of your current predicament?



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Once again, thanks for your continued interest. You've probably covered as much as there is to say about my wonky boiler problem. Today I'm going to go up to the compound and put everything to the test - 1) try turning the power switch from gas to electric to see if that stops the fan. 2) unplug the connections at control B to see if the fan keeps turning (although I've done that already, as you know - and it didn't cure the poblem) 3) unplug the cabling individually at the pcb - then reconnect, one by one, to ascertain if one of the connections affects the running of the fan. I'll let you know the results as soon as I get back. Thank you for all your time and for putting on your thinking cap, day after day, to try to solve a very puzzling problem for a stranger up North. That's real comradeship!

Steve - Lancashire lad.



You've looked at another aspect of the trip to the Alps and come up with some very sensible observations - and I'm grateful. I've been either camping, caravanning, motorhoming and climbing in the Mont Blanc Massif since I was in my teens, 40 years ago, so I'm aware of some of your conclusions. I know it gets really cold, even in summer, because the town of Chamonix is over 3000 feet in altitude. Of course, it's much more comfortable in a motorhome these days than when we used to bivouac under the fir trees, so I'm not really complaining, even with a dodgy warm air central heating system.


I've actually got a French butane bottle from the past and the pigtail and tools to go with it - but it's been used more for cooking than heating. I can fit two UK gas bottles into my Cheyenne locker - either two 7 kilo butane or two 6 kilo propane. In anticipation of cold weather, I've bought two of each, together with the different pigtails, so that I can move quickly from butane to propane at minus temperatures.


The one problem I do worry about is one you pinpoint yourself - that of fresh or waste water tanks and pipes freezing up under the motorhome - and I don't have any lagging or supplementary heating to keep them thawed out - although I did see that an American chap had used a candle - apparently without incident - to give a low heat to the underside of his RV. Hmm? I'm not advocating it myself though - I wouldn't like to blow the vehicle up! What I have planned, however, is to fill some large plastic containers with fresh water to keep inside the vehicle, on the understanding that, if the pipes freeze underneath, I'll at least have running water to wash with or make a hot cup of tea etc.


If I find a site close by, some of these problems could be made easier, so I shan't forget your advice that the electric hook up should be kept well clear of the ground, in case it gets welded into the snow and ice.


Thanks again for your thoughts on my problems. If I survive the trip without getting frost bite or losing limbs and other extremities, I'll be sure to let all those who've given me such timely advice know that it was all down to them. Thanks again!

Steve - in the Northern Territories.



Thanks for your input into my motorhome heating problem. I'm very impressed by everybody's contributions. I think you're absolutely right about taking an electric convector or fan heater and it's something I've considered and included in my plans - 1) because it's very convenient 2) because it doesn't share the same risks as a portable gas heater and the possibility of carbon monoxide poisoning. Of course, if the warm air central heating in the motorhome actually worked, as it's supposed to, that would be fine too. Your suggestion, which I like, is all dependent upon finding a camp site which is open - not always the case in the Alps in winter - and being able to hook up to electric power. I also like your idea of putting an inline car switch into the cabling to the fan - but whether I'd cut the correct cable or not is a bit speculative for someone like me and I could end up sabotaging myself if I weren't too sure. I'll look into it when I go and experiment later today. Meanwhile, thanks so much for all your thoughts and ideas.

Steve - up North but south of Hadrian's Wall

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northernsteve - 2014-01-19 9:50 AM


...I also like your idea of putting an inline car switch into the cabling to the fan - but whether I'd cut the correct cable or not is a bit speculative for someone like me and I could end up sabotaging myself if I weren't too sure...


Even if you put a switch into the cable that supplies 12V power to the circulation-fan, in order to isolate the fan-motor, this might well not prevent the heater from attempting to fire up on gas when you turned on the habitation electrics. With the fan rendered inoperative I would expect the heater to rapidly go into fault-mode, but the ploy is really no better than your 'set room temperature to minimum' work-around.

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Hello Derek! Here's a quick update on where I'm up to . . . I went to renew my combat with the Truma warm air central heating system on Sunday and tried out your suggestion of turning the left hand power switch to electric operation, rather than to gas, to see if it would deactivate the fan. It was always a possibility but sadly, it didn't make any difference - the fan kept whirring round. Then, I first wiggled around the connections on the pcb and finally disconnected them, all to no avail. I think I might only have found some of them and not all, so I might have another bash today/Monday.


I think you're probably right about inserting an inline switch not really affecting the operation of the fan and it's probably doing the same thing, as you suggest, when I turn down the thermostat on the rotary switch.


Anyway, I'm much buoyed by your and everybody else's interest and concern so, if it's impossible to repair in the next few days, the best thing I can probably do is to book it in at Truma to get it diagnosed and sorted on my return from the Alps. Thanks for all your efforts Derek - I'll be in touch. You raise the spirits!

Steve - Northern light.



Greetings Brian! Like Derek, you're another stalwart of the motorhome forums and I don't know what chaps like me would do without people like you, who spend so much time putting their mind to a complete stranger's problems - it's a magnificent service! Thanks too for your confidence in thinking that I might have covered most of the necessities for a successful alpine holiday.


I haven't yet resolved the warm air central heating problem but I tested out a small portable gas heater and it made a difference to the warmth inside the motorhome (I'm carbon monoxide and ventilation aware) so it's a fallback possibility if all else fails and I can't get on a site to run an electric fan heater.


I've also purchased snow chains, as you suggest, but not yet practised putting them on - something which is strongly advised, so I'll give it a bash before I learn the hard way and get bogged down with freezing hands on the Col Des Montets. Apart from that, the motorhome has been serviced and we're almost ready to go. I've climbed for decades but never been skiing before - just hope I make it to the piste in one piece! Thanks again Brian! I'll send back a report at a point in time.

Steve - Lanky Lad


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