Mondial Heating problem

[Amanda]

First posting and it has to be a problem!

 

We took delivery of a brand new Mondial this weekend and spent two nights trying it out. Everything was fine, apart from the rattles that have to be ironed out but the biggest problem is the heating!

The first evening we sat there with the heating on and everything seemed to be fine until it suddenly went into overdrive and blew like crazy. It then switched itself off and the red fault light appeared on the board. We had to switch off the heating and the power in the van, allow the system to reset itself before switching it all back on. The heating then worked fine until the second night. At 4am in the morning the heating did exactly the same thing waking us up with the racket of the fan blowing. We had left the heating on overnight on the lowest setting as it was so cold but had to get up and switch it all off and on again. Not funny at 4am! Turned it up slightly for breakfast and guess what ? It did it again.

We went back to the dealer who seems to think this is normal for the system. My question is, is this normal? We are going to Scotland in April and will probably need the heating on quite a bit. So are we going to have to keep resetting the heating system if we leave it on for long periods of time. has anyone else had this problem?

Many thanks .

[PJay]

Hi Amanda

You do not say what fuel you were using i:e Gas or electric, this may help someone to help you.

Welcome to the forum, you are bound to get a lot of good advice

PJay

[Robinhood]

I believe the current Mondial has the Truma Combi 4 Gas and Electric heater.

 

Whilst declaring the behaviour normal is always a matter of degree, it is a feature of the Combi system, when used on Gas, that the fan will operate very quickly some time after initial switch-on, in order to disperse the heat, which is likely to be at full output at that time. (If it didn't, the unit itself would overheat).

 

It has been described by some as being a bit like on a jet at take-off. (And a smallish panel-van conversion will amplify this effect).

 

It usually settles down quite quickly, as the level of heating is adjusted automatically to meet the demand set at the thermostat. i.e. over time, the amount of gas being burnt is reduced to maintain 'room temperature' , and the fan slows down as it doesn't have to disperse as much heat.

 

The interval obviously depends on both the ambient temperature and the thermostat setting, but it is still likely that the fan will run at full speed for some time at any combination of these.

 

As the potential heat output is much lower on electricity, the 'jet engine' effect tends to be absent when used in this manner, and if I have a hook-up, I only ever use the electric setting and low thermostat overnight (and have never been cold, even in much bigger 'vans).

 

The red light coming on, however, is not a normal occurrence, and a steady red light normally indicates a lack of gas supply.

 

I would check:

 

1. That the gas is turned on and any isolating tap for the heater is also on (though your post implies this should not be the problem).

 

2. You are using propane gas (red bottle) rather than butane (blue bottle) - the latter fails to gas at temperatures such as we are experiencing at the moment.

 

3. The gas regulator - they are known to be prone to faults.

 

I think you are probably stuck with the noise (on gas at least) but having to reset the heating to get rid of the light is not normal - back to the dealer if you can't resolve.

 

HTH

[Brian Kirby]

One reason for the heater suddenly switching off with the red light on might be if you don't have enough (or any!) of the outlet dampers open, causing it to overheat.  Worth checking that all are open to the full extent, before tackling the dealer again.

Our van has the earlier Combi (gas only), and it takes several minutes after firing up before it finishes sampling the internal air temperature and switches up the fan speed.  It then runs at full chat (747 mode :-)) if it's cold enough, until it reaches the set point, and then progressively backs down until, if the internal temperature stabilises near the set point, it dies to a tickover whisper, eventually turning the fan off if the temperature rises further due to, for example, solar gains.  I would imagine the control logic on the newer ones would give broadly similar behaviour.  Hope this helps.

[Robinhood]

Brian Kirby - 2010-11-14 11:55 PM

One reason for the heater suddenly switching off with the red light on might be if you don't have enough (or any!) of the outlet dampers open, causing it to overheat.  Worth checking that all are open to the full extent, before tackling the dealer again.

Indeed, if the failure is happening well after starting and whilst it is running in '747 mode', then overheating is a distinct possibility. Make sure all outlets are open, AND also ensure that any inlet vent to the area in which the unit is mounted is not blocked or obscured (it effectively recirculates the air inside the 'van, and therefore needs to intake air as well as output it).There is a troubleshooting guide at the end of the operating instructions that should walk you through the appropriate checks.Just an extra thought, but if it is overheating then this is likely to exacerbate the fan noise, as I would expect the fan to run at full speed to attempt to cool the unit down.

[Derek Uzzell]

Amanda

 

I echo what's already been advised.

 

Truma Combi heaters do have something of a mind of their own, but owners soon learn to accept their funny little ways.

 

If you haven't got a copy of the Operating Instructions for your heater, then these are downloadable from Truma's main website. As RobinHood says, they contain a trouble-shooting section that may help you to identify why the red 'fault' light came on or (if it happens again) help you to resolve the problem. The latest "Combi" heaters produce a diagnostic 'code' on their control-panel if there's a fault and the code's meaning is given in the instructions.

 

Once the heater has gone through the start-up and room-temperature adjustment phase, I wouldn't expect it do your 4AM thing. It's possible that your heater's remote thermostat (that senses room temperature) is oddly positioned (a motorhome manufacturers' favourite trick), but who knows? Perhaps you were using Mixed Mode (230V + gas) as that might cause that behaviour?

 

Finally, don't fiddle with the control-switch settings unnecessarily - all this will do is 'confuse' the heater. Just let it get on with it.

 

[mel wood]

Hi Amanda and welcome.

I hope you get to grips with your heating soon. Whilst not solving your problem with the supplied heating system, I'll let you know what we find most suitable in our panel van.

In cold weather we have electric hook up and use a small electric panel heater (bought at a reasonable cost at Argos). It is usually sufficient to provide a suitable level of heat and can safely be left on overnight, if required. If the weather is particularly cold or we need an extra boost we use a small electric fan heater. This also proves effective if we need some extra heat to dry waterproofs. the hot air circulating dries them effeciently when they are hanging up.

Both these heaters are small enough to store easily in our van.

[dshague]

we have the same van as you . but have not had this problem .

witch type of gas are you using.were you on gas/electric .you can ask here if you want to double check your problem  http://www.swift-talk.co.uk/

[Amanda]

Hi everyone and thanks for your quick replies.

 

We were running the heating and water on electric only, water being on the highest setting (60 degrees) and the heating being on 2. The 'jet engine take off' noise didn't start straight away but after a few hours. Up to then the heat had been gentle, quiet and efficient. When it did cut out the first time we waited to see if it would come back on but it didn't.

The operations manual seems to suggest that its the outlets that are blocked but I did check these and they were clear, unless I missed one! Every other idea they suggest seems to refer to gas and as I said we were running off the electric. Baffled.

Anyway I have posed the question on the Swift site and am awaiting a reply. Will let you know what they come back with.

[woody.]

I had the new mondial , never had any problems with the heating , and when you turn the heating off the fan does blow like crazy to clear the hot air from the system , i would say the problem is consistant with the heater being turned off , i reckon youve got a problem with an electrical connection somewhere , seems like the power is cutting itself off when the system gets hot .

[woody.]

I had the new mondial , never had any problems with the heating , and when you turn the heating off the fan does blow like crazy to clear the hot air from the system , i would say the problem is consistant with the heater being turned off , i reckon youve got a problem with an electrical connection somewhere , seems like the power is cutting itself off when the system gets hot .

[Derek Uzzell]

Amanda - 2010-11-15 9:26 PM

 

Hi everyone and thanks for your quick replies.

 

We were running the heating and water on electric only, water being on the highest setting (60 degrees) and the heating being on 2. The 'jet engine take off' noise didn't start straight away but after a few hours. Up to then the heat had been gentle, quiet and efficient. When it did cut out the first time we waited to see if it would come back on but it didn't.

The operations manual seems to suggest that its the outlets that are blocked but I did check these and they were clear, unless I missed one! Every other idea they suggest seems to refer to gas and as I said we were running off the electric. Baffled.

Anyway I have posed the question on the Swift site and am awaiting a reply. Will let you know what they come back with.

 

I hesitate to contradict you but, if your Truma heater had been set to run solely on 230V mains power, it's very unlikely that it would have behaved as you have described. I believe that (as I suggested earlier) it's more probable that you had inadvertently selected "Mixed Operation" (230V + gas) on the Power Selector Switch instead of "Electric Operation" (230V only).

 

When a Combi heater is in 'Mixed Operation' mode, it will select 230V as the priority power source but, if the temperature in the vehicle's interior falls below the room-temperature setting you've chosen on the heater's control panel ("2" in this case) and the heater 'recognises' that 230V heating alone is insufficient to maintain that temperature, then the Combi will choose to bring gas operation into play until the room temperature has reached the required level. Basically, in mixed-mode, the heater will run on 230V most of the time, switching to gas only when it feels it has to.

 

When the heater does switch to gas, if the room temperature in the vehicle has dropped considerably, then you should expect the heater to run flat out for a while (eg. like a jet engine) in order to raise the room temperature rapidly.

 

I doubt that there's anything wrong with your heater. I believe it's doing exactly what Truma designed it to do, but (it has to be said) this isn't wonderfully well described in the heater's Operating Instructions.

 

When you want to operate the heater SOLELY on 230V, make certain that you turn the rotary control on the Power Selector Switch from its centre position "d" (gas only operation) anti-clockwise to position "c" (900W output) or "b" (1800W output).

 

If you rotate the control clockwise from position "d" to "e" (900W + gas) or "f" (1800W + gas), then you'll put your Combi into Mixed Operation(230V + gas) and it's quite likely it will give you another 4AM wake-up call. :-D

[bolero boy]

Hi there, we have a Truma Combi in our 2010 Bolero 680FB. In gerneral, the 'jet engine' syndrome is only apparent in gas or mixed mode but, just occasionally, I have noticed the blower moving to the max when on electric only.

 

This is unusual as we normally use 240v on EHU and the fan is mostly unobrusive. However, one day we came back and required more of a 'blast' so turned up the thermostat to 5 but kept source on 240v. The fan did speed up for a short while until the temp picked up.

 

The fan also runs fast after switching off from 'hot water only' or 'heating/hot water' modes in order to cool the system's internals.

 

Rgds,

Chris.

[Derek Uzzell]

bolero boy - 2010-11-16 10:40 AM

 

...The fan also runs fast after switching off from 'hot water only' or 'heating/hot water' modes in order to cool the system's internals.

 

Rgds,

Chris.

 

Interesting that, as my earlier C-6002EH only runs the blown-air fan when the heater is switched off if the appliance has previously been in blown-air mode. If only water-heating has been operating, when the heater is switched off the fan doesn't kick in. This makes some sort of logical sense as, if the weather is warm and you've just been using the appliance to heat water, you won't really want hot air to be blown around the motorhome's interior as a side-effect.

 

Anyway, it definitely sounds like whatever Amanda's heater is doing, other people's heaters are doing the same and it shouldn't be anything to worry about.

[Keithl]

Amanda - 2010-11-14 10:22 PM.

It then switched itself off and the red fault light appeared on the board. We had to switch off the heating and the power in the van, allow the system to reset itself before switching it all back on.

 

OK, so if all is fine why did it shut down and show a red light requiring a power down reset before it would work again?

 

Keith.

[Derek Uzzell]

Keithl - 2010-11-16 3:30 PM

 

Amanda - 2010-11-14 10:22 PM.

It then switched itself off and the red fault light appeared on the board. We had to switch off the heating and the power in the van, allow the system to reset itself before switching it all back on.

 

OK, so if all is fine why did it shut down and show a red light requiring a power down reset before it would work again?

 

Keith.

 

Yes, I agree that's a worry.

 

If the heater continues to do this and there's no obvious explanation for it, then there's something wrong with the appliance or the installation. As Amanda is still unfamiliar with the Truma Combi, I think she will need to use the heater for a while and see how things go. Assuming that Amanda's heater hasn't done the red-light/reset thing again, what alternative course of action would you recommend?

[Keithl]

OK, my thoughts...

 

Seen as it is a brand new van and has done this since day one and Amanda has quoted from the manual...

Amanda - 2010-11-15 9:26 PM

The operations manual seems to suggest that its the outlets that are blocked but I did check these and they were clear, unless I missed one!

 

Then my thoughts would be that if all the vents appear open is there possibly a crushed duct somewhere between heater and vents causing the problem?

I recall another forum member recounting the tale of his crushed ducts and how he had to reroute them so is this a possibility?

 

Got to be worth checking before heading back to the dealer.

 

Keith.

[Amanda]

Ok guys, thanks for all the comments. Seems I have started a debate here. I have not heard back from Swift yet but will let you know when I do.

 

Derek, the system was DEFINATELY running on electric only and not gas/electric mode. Maybe we should try running the heating only on electric and see if it happens? We are hoping to get a few more weekends out before the trip to Scotland and hopefully we can get to the bottom of this before then.

We will have to hunt around and check all the duct work and just make sure its ok. But I'm of a mind that if the thing switches off and the red light comes on there has to be something wrong. Always get suspicious of red lights (lol)

[Amanda]

The reply from Swift is the same idea as all of you. We have now checked all the ducts, vents and pipes and there are no restrictions or blockages anywhere. So, back to square one.

The only thing we think it can be is the heating element is just overheating in which case I guess its back to the dealer for them to check it out. Hopefully before we do that we can find a day to try it again. For now we have drained down the van ready for the winter so it probably will need a day for us to fiddle with it.

Any idea where we might find the thermostat? Just wondering if its been placed in a daft place and that might be affecting it.

[Brian Kirby]

It seems clear neither the dealer nor Swift understand these units adequately: but why aren't I surprised by that?  :-) 

My suggestion, therefore, is for you to contact Truma UK directly.  Their technical bods are usually very helpful.  Rather than trying to explain the whole lot over the phone, see if you can get agreement to e-mail over the details for them to think about.  That should get either some sensible suggestions, or maybe some instructions on where to look for further clues as to cause.

If you can get to them, they also have a reputation for being very helpful in fixing problems - but only by arrangement, not a drive-in service.  Due to the way some manufacturers install the heaters (in tight corners with poor access!), any remedy that requires removal of the heater can be quite a long job.  Don't know if they have roving engineers who would visit your dealer as an alternative, but it may be worth asking.

[Derek Uzzell]

Keithl - 2010-11-16 7:16 PM

 

OK, my thoughts...

 

Seen as it is a brand new van and has done this since day one and Amanda has quoted from the manual...

 

Then my thoughts would be that if all the vents appear open is there possibly a crushed duct somewhere between heater and vents causing the problem?

I recall another forum member recounting the tale of his crushed ducts and how he had to reroute them so is this a possibility?

 

Got to be worth checking before heading back to the dealer.

 

Keith.

 

I was the 'crushed duct' victim. It was immediately obvious there was a fault as no hot air was emerging from the lounge-area outlets. A Truma 'combination' heater, correctly installed following Truma's recommendations, should (in theory) be capable of distributing hot air in a balanced and efficient manner throughout a motorhome with all the air-outlets fully open. My Hobby's system, after my major modifications, can do this and, to avoid the risk of accidentally closing off an outlet and possibly overheating the appliance, I've removed all the outlets' 'butterflies'.

 

I believe I may have misunderstood Amanda's problem, thinking that the red-light shut-down had occurred just once and that her other observations related just to the heater suddenly producing 'jet engine' noises. I now understand that the heater has red-light shut-down several times accompanied with the fan running at high speed, which definitely ain't right.

 

The Operating Instructions for the Combi 4E/6E

 

http://www.truma.com/downloadcenter/combi4e6e_instruction_fr.pdf

 

seem to suggest that a steadily illuminatied red-light indicates a gas-related fault, but it will be evident from the trouble-shooting section on Page 16 that there are lots of alternatives where the red light flashes and/or illuminates in combination with the other read-out lights.

 

I can't say where the heater's room-thermostat will be in a Mondial, but it usually seems to be installed near to the heater's control switches. It's a small black plastic dome as shown on Page 12 of the Operating Instructions.

[woody.]

I had the new mondial as i said earlier , but i cant for the life of me remember even seeing a thermostat anywhere , Amanda i reckon you ought to ask swift about this one . (?)

[Mike88]

Woody. The thermostat is minute - blink and you'll miss it. Its a sensor with no adjustment and not what most people would ordinarily regard to be a thermostat in terms of appearance. Its located on the near side rear quarterlight and is only about 1cm in diameter.

[Amanda]

I have now had a couple of replies from Swift and they cannot explain this and suggest it goes back to the dealer. So it seems this is what we may have to do. I might try Brian's suggestion of contacting Truma first and see if I can get anywhere with them.

Thanks to everyone for your advice/suggestions and comments. As a newbie hubby and I really appreciate your help.

 

Look forward to posting more (hopefully not problems) in the future.

 

Cheers.

[Connie]

TRUMA combi 4E/6E

 

We purchased a brand new Autocruise Startrail at the end of July 2009 and only at the end of August 2010 were our problems with the combi boiler resolved.

 

Unfortunately, our dealer was less than helpful. Therefore in our frustration we turned to TRUMA in Derbyshire who were absolutely brilliant. Although, initially not quite believing our boiler problems - "jet engine" noise followed by whole system shutting down, with control dial showing a flashing red light - they at least did attempt to investigate.

 

Subsequently, our motorhome was fitted ( by TRUMA in Derbyshire ) at first with a replacement boiler, followed throughout the year with two replacement printed

circuit boards, unhappily our problems persisted ~

finally ~ after ongoing investigation between TRUMA in Derbyshire and TRUMA at their headquarters in Germany the fault was diagnosed as a

VOLTAGE SPIKE, too much current travelling to the air circulation motor resulting in the PCB shutting down because it, incorrectly, recognises an overload.

This, obviously, only happens when connected to an electric hook up.

 

As this was our first motorhome it has certainly been frustrating and with a dealership who were only interested in selling with no after sales service we can only feel more than grateful to TRUMA in Derbyshire for their outstanding help.

 

Retrospectively we should have rejected this van at the outset, but of course there is a time limit to this and, as 'first timers', we initially thought the problem was with us !

 

Amanda - I hope this has been helpful, my advice would be contact TRUMA in Derbyshire as it appears you also need a PCB made in Germany specifically for this VOLTAGE SPIKE problem.