Truma Water Heater Problem

Two Sikhs fills is hardly enough  water for a shower

Thanks for that. Two sink fills is hardly  enough  water for a hot shower

I've just tried to turn on the heater to use electric to warm the camper. Now I need to find out what W45H is . . . . .
I might as a last resort have to look at the instructions . . . . .
but being a bloke I would have to do that after dark in the under-stairs cupboard with a torch, so no one would see me .

I wonder why the "polarity reversed" light is on on my Sargent. I don't think that would cause a W45H would it? Or how about the gas is turned off, would that cause it, even when I have chosen electric and low. I know if you put it on high, it uses both gas and electric so then it would throw a wobbly but surely if you only want it on low it should work when dry, and on electric only.

I'll have to go and look it up . . . . and puzzle where that reversed polarity light comes from. I have tried two different extension leads from the house and that makes no difference. I used to have a polarity checker but as I will never need it again, I sold it. . I'lll try different house-source sockets, garage, kitchen, lounge. I have had the Sargent front panel off to rewire the solar charger better, and all the colours of the mains wires looked correct. You can't have blue electrons going down a brown wire, can you?

By the way I have before now removed the under-wardrobe panel, disconnected all the pipes and pulled the boiler out just to check that fuse. To me, that is reason enough to go and find a different camper, I can't be doing that all the time.
Speaking as a retired gas man, including leisure vehicles and LPG, I can understand to some extent why there should be a particular way to install a flue in a leisure vehicle. A/S don't do it properly, and if they aren't going to do it properly as the manufacturer instructs, then if we can, we should be free to re-install it either as the manufacturer says. Either to facilitate maintenance or to just run the flue where they say it should run. I suspect the reason for their specific mounting and flue-running specification is to allow for fast flowing wind past the flue, and to regulate the volume of air entering, and exhaust gas exiting, the flue terminal. To that end I personally think it might be feasible to rotate the boiler 180 degrees. I must be wrong though, surely A/S tried it? Would the flue length would be different? I can't remember but I doubt that the small difference would matter. On domestic boilers, longer flue lengths can be accommodated by removing a restrictor but that only comes into play if you have a flue length in excess of about 3 metres.

Truma manual:

Special features in electric mode
The manual says:
– If the 230 V power supply is interrupted and the 12 V supply is switched on, an fault code is shown on the display.
– When the 230 V power supply has been restored, the heater is automatically started with the existing settings. The fault code goes off.

Oh no it doesn't!

It says W45H is a 230v fuse, to replace it see operating manual. I can't find anywhere in the operating instructions that tells you how to replace it. In any case why would it have blown when all you have done is fail to observe the complex switching on procedure that was determined by the NASA Saturn Rocket launching team?

To save you looking up the Truma code;-
W - is a warning!
45 - is telling that there is no operating voltage!
H - is (as you have guessed) the failed device (heater/boiler)!

gassygassy wrote:Truma manual:

Special features in electric mode
The manual says:
– If the 230 V power supply is interrupted and the 12 V supply is switched on, an fault code is shown on the display.
– When the 230 V power supply has been restored, the heater is automatically started with the existing settings. The fault code goes off.

Oh no it doesn't!

It says W45H is a 230v fuse, to replace it see operating manual. I can't find anywhere in the operating instructions that tells you how to replace it. In any case why would it have blown when all you have done is fail to observe the complex switching on procedure that was determined by the NASA Saturn Rocket launching team?

Section 9-17 of my manual shows where the 230V fuse goes!
It must be a 10A - slow - (T 10A) fuse - I think it has a red band around it - any other fuse will blow!!

Sorry yes, I was looking in the wrong manual! I have found the diagram of the boiler, which has two fuses, neither of which are accessible unless you remove the boiler.

Anyway I am double fuming now, not only because for some peculiar reason the boiler thinks it has blown a fuse but I have just discovered why my Sargent has its 'reversed polarity' light on.
The *@^&@)£^£$W flipping toe rag incompetent shoud-be-unemployed idiots that installed my electric car charging point outside my house have wired it with the reversed polarity! The Lord Above only knows why they are employed. They should be sweeping up the contaminated medical items off the floor of a Covid operating theatre. Then the world would be a better place.

Suddenly I like the Sargent!

"Or how about the gas is turned off, would that cause it, even when I have chosen electric and low. I know if you put it on high, it uses both gas and electric so then it would throw a wobbly but surely if you only want it on low it should work when dry, and on electric only."


the Combi only uses the fuel types selected....
if thats gas, it only uses gas....if its EL1/EL2 it will use only electric at the wattage specified.
however, if 'mixed' is selected, it will initially use both gas and electric with the level of gas used reducing as the van gets up to temperature, eventually running on electric only...this is what makes it a great choice for speedily heqting the van withput having to think about changing fuels...

The truma combi e holds 10 litres  of water if use the  bathroom sink and the wife uses  kitchen sink .that is not 10 litres  of water. But the water symbol  flashes on the control  panel to say  hot water is heating.is this normal? If you used all 10 litres   I could understand  it 
.

Mids wrote:The truma combi e holds 10 litres  of water if use the  bathroom sink and the wife uses  kitchen sink .that is not 10 litres  of water. But the water symbol  flashes on the control  panel to say  hot water is heating.is this normal? If you used all 10 litres   I could understand  it 
.

As Paul explained earlier on, the moment you draw hot water, cold water enters the hot water tank which needs heating hence the water symbol flashes.

Mids wrote:The truma combi e holds 10 litres  of water if use the  bathroom sink and the wife uses  kitchen sink .that is not 10 litres  of water. But the water symbol  flashes on the control  panel to say  hot water is heating.is this normal? If you used all 10 litres   I could understand  it 
.

Yes, that's normal!
Its works like any immersion tank - for any amount of hot water that you draw off it is replaced at the same time by an equal amount of cold water and consequently dropping the temperature in the tank/boiler such that the sensor tells the system to commence heating again.

tee hee. I have spent most of today removing the boiler, rotating it 180 degrees so that the electrics panel will be just inside the ventilation grille under the wardrobe drawer. I haven't finished it yet, I need to wait till Friday before I can get some more corrugated warm air tubing. So far so good. I will at any rate be able to get it going later today - now that it is tomorrow. Timed at 00:06 Thursday

gassygassy wrote:tee hee. I have spent most of today removing the boiler, rotating it 180 degrees so that the electrics panel will be just inside the ventilation grille under the wardrobe drawer. I haven't finished it yet, I need to wait till Friday before I can get some more corrugated warm air tubing. So far so good. I will at any rate be able to get it going later today - now that it is tomorrow. Timed at 00:06 Thursday

That’s brave!  I’ll be interested to know if you discover any disadvantages to having it this way around.

I can't think of any disadvantages, can you? It will run off mains or gas, all the original hot air outlets will stay where they are, no part of the motorhome will be cut or drilled, it will look exactly the same as it did before. The advantage will be that the electronic circuitry which is prone to overheating will be close to the grille so it will run cooler. Having a research and development background in electronics I am very aware of the effects of high temperatures on component longevity. Quite apart from that it will make the installation a lot closer to the manufacturer's installation instructions, which A/S seem to have chucked in the bin. Access for fault finding and rectification will no longer require the entire boiler to be removed from its enclosure.
Maybe I will find out why A/S install them as they do, and not this way round. I think the flue terminal should be lower than it is, because I suspect the drawer might foul the flexible internal flue tube. . . . . . .we'll see.
Anyway it's not brave, it is just experimenting. I love experimenting. What I call brave is a job I did about ten years ago. I converted a LHD Burstner to RHD successfully. I also ripped out the 1.9 Useless Engine and slotted in a 2.5 turbo which made it go properly. I traded it to a dealer who never even realised that Burstner never made a RHD motorhome in those days.
If I could understand how my Apple MacBook stores photos I could attach one or two. I have the file names, I can see the photos ordinarily, but when I try to attach one to an email it just will not goto and attach it, even when I type in the file name.

If there was any chance at all of getting an honest answer (IF!!!  ) it would be good to ask Messrs A/F why they mount it that way round.

Presumably there is/was a reason, or is it simply that it's just a bit easier for them to install it that way round?

I think the main reason is that the exhaust outlet should face the external wall, not the inside of the vehicle. That is what the Truma installation guide shows.

The combi should be perpendicular to the external wall it faces, with the heat outlet end towards the external wall. 
The exhaust pipe the runs from the inside part of the unit, across itself and exits at said external wall, the installation diagram looks pretty clear in that regard.

Chris so Autosleeper’s do fit some correctly 

That still doesn't comply with all the details in the picture earlier in this thread. However it is of course better than the Nuevo fitment. I've nearly finished mine. A/S could fit it like that in the Nuevo, I checked all the measurements. The only thing with that config is that the cover of the electronics panel is obscured by the warm air pipe. Also on the photo above, the warm air pipe at the front of the photo is blocking or at least restricting air flow into the motor cooling fan.
I've checked that mine works correctly, I just have to reconnect the hot water pipe and find out how to extend one or two of the warm air pipes.
Also to a logical thinking person you woudn't need the mains switch labelled "Water Heater" to be on if all you wanted was hot air from the boiler. If you want hot air but not hot water, why would you want to turn on the water heater? It should say "Combi Boiler" I think. But then I am a logical person who used to write user manuals for a large company.

I did look at the space at the air intake pipe as it was a bit lower down so I have moved it up as high as it would fit and is now clear of the air intake And not blocking the flow coming in from the vent  in the seat base

yes Glyne, youre right....this is the correct orientation....
however, re the mentioned heating pipe....in an ideal install the Combi should be sited centrally so that two of the pipes head rearwards while the other two head fowd, thus negating the situation in the photo of having a rearward vent pipe doubling back in the 'wrong' direction...
this generally happens when units are sited well to the rear or right at the front, which also makes it dofficult to ensure an even spread of heat from each of the four vents...
forums are full of posts like asking why is the rear so hot when the front is cold?
its not rocket science.

Yes it has drifted a bit. Must be all the hot air around here!
I have finished the rotation, it works fine. It does involve the purchase of a few parts namely

One tin of Morrisons Garden Peas
One metre of orange 2.5 T&E cable (you can't suddenly ask orange electrons to run along a grey wire can you?
One metre of red/clear water pipe (I went all anti-establishment and used some blue/clear pipe, I hope the hot water can cope with it )
One 8mm compression coupler for the gas pipe

That's about it really. Naturally as with any job you end up with a small saucer of unknown, apparently not necessary screws and a couple of unwanted and unnecessary warm air pipe clips.
I'll start a new thread in case anyone feels inclined to waste a couple of days doing it. I guess we have all run out of jobs we meant to do sometime, which have now got done.

That air intake glyne is neither the combustion air or the warm air circulation inlet. It is just a vent with the blower motor fan inside it. That fan is just to keep the blower motor cool, not to blow air around the van. It's probably fine.