How to rotate your Truma boiler through 180

On my Nuevo, as with I guess everyone else's and all other A/S models with the boiler under the wardrobe drawer, all is well so long as it is working. If the overheat trip goes 'ping' or the fuse goes 'pop' you either need a Victorian chimney sweep starved three year old to get in there and fix it, or you can rotate the boiler through 180 degrees so as to fit it in accordance with the Truma fitting instructions. Once you have done that, access to the electronics and the pcb is a five minute job of removing the vent under the wardrobe. The other four minutes are for drinking a cup of tea.
Roughly speaking it goes like this - it's a few weeks since I did it so I'll have to try to remember.
1) remove the drawer and the front timber panel from the frame.
2) turn off the gas supply and the mains electricity supply, disconnect the leisure battery.
3) set about disconnecting anything that is connected to anything else. Mains wire, 12v wire, signal wires at the boiler plug, water pipes, gas pipe, warm air hoses and flue hose. Pull the warm air hoses out of the boiler and set them to one side so they don't clutter up your work space. The flue hose is two pipes, one inside the other and they each have a jubilee clip holding them on. Leave the wall outlet connected.
4) Unscrew four screws securing the boiler to the timber floor. You will need the scrawny three year old to get at the ones at the back with a long philips screwdriver. Or you will need a LED light, and a three month course in yoga to do it yourself.
5) Rotate the boiler through 180 degrees and start to consider how to reconnect everything. Consider any restrictions and screw the boiler to the timber floor. The screws will not fit in the same holes and you will be very skillful if you can get all four in place.
6) Mains wire: extend this to reach to the new position. I can't remember if the same applies to the 12v supply, obviously these two things are easily done. The small wires for the boiler controls can be plugged back into the boiler without extending them.
7) Gas pipe. From memory this is 10mm diameter. It is long enough, you don't need to extend it but you do need to cut it so it will swivel round through 90 degrees, and you may have to bend it a bit to reach the gas inlet point. Cut the plastic covering around the copper gas pipe so that using a proper pipe cutter you can cut it where it drops vertically, a bit below the drawer runner. Go and buy a small pipe cutter if you don't have one. Using a junior hack saw will leave a bevelled cut with rough edges and bits of copper swarf which will get into the boiler gas jet and block it.

Bend the pipe as necessary to fit the new position of the boiler gas inlet, and screw the boiler end into position loosely so it takes the thread, but can still be manipulated without twisting the copper. It should be long enough to reach the cut end of the supply pipe by the drawer runner. With both cut ends of pipe clear of plastic sheathing, connect the two with a 10mm brass coupler and olives. Use a proprietary gas thread sealer - you can use Calor sealer, or there are several other brands available from your nearest plumbers merchant or B&Q. Do up the joint nice and tight but don't use gorilla force or you may crush the copper pipe. Now tighten the boiler connection. That's the gas and both electrics done. Reconnect the low voltage sidgnal wires with the plug that pushes into the boiler control panel.
8) Water pipes. These will need a bit of cutting, shortening and lengthening. You may need a metre of pipe from your motorhome accessory shop or ebay. It is always 12mm o/d, so none of the connectors from your plumbers merchants will fit, we only jump from 10mm to 15mm whereas the Europeans and UK motorhome and caravan manufacturers use 12mm. You can either couple the water pipes with proper expensive couplers from your caravan accessory shop or you can cut off a bit of 10mm copper pipe, push it inside the plastic pipes and secure it with two jubilee clips.

Note that contrary to popular opinion you can have red water going along a blue pipe, it's all the same plastic. This is a result of turning the boiler round so you can re-use excessive lengths of pipe you cut off earlier.
Reconnect the water pipes to the boiler, and to their run-out pipes leading away from the boiler to the taps. Make sure the red (hot) water pipe connector at the boiler is pushed in firmly. You will need a short length of clear plastic pipe to extend the over pressure relief pipe to connect it to the existing pipe that runs down outside.
9) The Boiler flue pipe. This is a co-axial pipe, one (aluminium) pipe inside an outer (plastic) pipe. You will have noticed when you removed it from the boiler that it has a very strong jubilee clip holding the inner aluminum pipe to the boiler outlet flue. It is very important that you refit this firmly and fully, and tighten the fat jubilee clip as tight as you can. Do this before attempting to refit the outer plastic pipe. The inner pipe takes away the burnt flue gases and the outer pipe brings fresh air into the boiler. Having clamped the inner pipe firmly, fit and clip the outer black plastic pipe to the outer ring on the boiler. You will need to stretch and bend the flue pipe to fit under the drawer - it will, just use whatever force is necessary to get it to submit to its new position. Don't worry about the outer pipe touching the inner pipe, it is bound to at some point along its length.
10) The warm air pipes. You will not need to buy any additional warm air pipe but you will need to juggle the pipe you have to feed all four outlets. Don't be afraid of bending this pipe - but don't bend it in half, crimping it so that no air can pass as the manufacturer did on the Pilote I bought once. Select the shortest pipe and fit it to the rear lower boiler output and take it to the washroom air vent. Similarly select whichever pipes you think will fit without cutting, and push them on to the boiler outlets. There will be one pipe that is unnecessarily long, and one that is too short so you can cut the long one so it is just the right length, and the surplus cut-off bit makes up for the shortfall of she short pipe. Here's a Cunning Plan, and you don't even need a turnip (the younger ones must consult old Black Adder episodes). Get any typical baked bean or peas tin, clean it and remove the label, and you will discover to your joy and delight that it exactly fits around the cardboard outer of the warm air pipe.


11) Fill the boiler with some water by having some in the tank, and switching on the 12v and opening a hot tap, till the bubbling and popping stops. Having filled the pipes with pressurised water, look along all their lengths and check for any leaks.
12) turn on the gas. There are two official ways of testing for a gas leak. One is the technical way that GSR engineers use with a manometer. You pressurise the system, turn off the supply and monitor the pressure drop over  a two minute period. Ideally the drop should be zero but in a house, a very small drop is permissible. In a small installation like a motorhome, any drop is really not acceptable. The other, and still valid, system is to apply gas leak detector fluid (from a plumbers merchant or indeed B&Q) to the joints you have disturbed at the 10mm coupler and at the boiler connection. This detector fluid will blow up enormous bubbles if there is the slightest leak. It is a most exceedingly bubbly liquid. If there is a leak detected obviously you must fix it. Having tested for either a pressure drop with the gas supply turned off, or for any signs of a leak with bubble fluid, turn on the gas supply.
13) reconnect the leisure battery, turn on the Sargent control panel.
14) Fire up the boiler, either by selecting hot water or heating and put the thermostat up to a temperature you know is well above the ambient.
15) If anything doesn't work, check why and fix it, check for any water leaks. Assuming all is well you will need to really squash the boiler flue pipe as hard as you can up against the outside wall in order for it to clear the drawer back. It will go, but you do wonder why the flue terminal is so high on the outside wall.
Refit the front wall panel and reinstate the drawer, clear up the mess you have made and make a cup of tea. Turn off the boiler unless you need a shower from all your hard work.

Now the boiler electronics are close to the ventilation panel under the wardrobe. Therefore that area of the boiler will run cooler than it did when the electronics were enclosed in a badly overheated place in between the hot boiler and the outside wall. Any electronic circuit will last longer and be less prone to breakdown if it is in a cooler environment. Not only that but if anything goes wrong the pcb can be got at simply by removing the vent panel instead of removing the whole boiler -or getting a Victorian 3 year old chimney sweep boy.

I have read the Truma boiler installation instructions and this is in my opinion how A/S should have installed them in the factory. I genuinely do not know why they install the boilers as they do. Perhaps they have a reason. Perhaps they look at this forum and can reply and say why they install them in the way they do. I might be fascinated or surprised to find out.
Lastly I will add that I am a retired Gas Safe Registered engineer and unless the rules have changed, it is permissible for the owner of a caravan or motorhome to work on their own gas installation. It is not permissible to work on someone else's. And of course unless you are confident in what you are doing, pay a qualified engineer to do it. However, I have written this knowing that there are some competent readers here who know how to work a spanner and a screwdriver and connect wires so if you want to do it and are confident, this is how it is done.

Excellent post, this one. I once had to reset the boiler on the Nuevo we had. About as much fun as a visit to the tax office.

Thorough guide for anyone who can tell the difference between Pozidriv and Phillips and a well worthwhile winter/off season job.

There is no excuse whatever for the factory still installing these units the wrong way round. I pointed this out publicly at an ASOC forum where factory members were on the panel and still the situation remains. Over 30 years as an AS owner the factory has consistently failed to act on owner feedback. 
Another example was the installation of the Zig units on Pescara models. This was put under the floor of the wardrobe which was constructed off chassis in a unit with the toilet compartment. Unfortunately, when the Zig unit failed it was necessary to cut the floor of the wardrobe out in order to gain access.

I've just re-read my post, and realised that before item 11) I omitted to say this is the point where you have to reconnect the leisure battery before the pump will work! Nevertheless I hope that people will realise this is necessary

Thank you for a very informative article.  Please excuse my ignorance, but how do you get the drawer out? I can't figure it out. Help please

oddjob wrote:Thank you for a very informative article.  Please excuse my ignorance, but how do you get the drawer out? I can't figure it out. Help please

Have a search.

This topic comes up every so often.

Here's one fairly extensive thread which should help.

https://www.autosleeper-ownersforum.com/t33479-nuevo-2011-water-system#286438

Thanks Gromit.  I have a much  better understanding now.

Thanks again,   Oddjob

Pleased I could help. 

oddjob wrote:Thank you for a very informative article.  Please excuse my ignorance, but how do you get the drawer out? I can't figure it out. Help please

The easiest way to remove the drawer is to not set the catch to the properly locked position and then take a right hand bend at about 40 mph.    It worked for me!

If you do it more than once, you will find that the 1 cm long screws holding the rails in place release the rails as well so you can then do a proper job of fitting the drawer.

oddjob wrote:Thank you for a very informative article.  Please excuse my ignorance, but how do you get the drawer out? I can't figure it out. Help please

Oddjob: just enquiring, why do you need to get the drawer out? Are you having some bother with the heater? If you have that heater you showed in a photo, you don't need to remove the drawer. The heater removes from the front, and in any case I have never heard of them needing to be removed. Have you dropped something over the top of the back of the drawer into the heater space? That's the only reason I think you would want to remove the drawer.
If you want any help diagnosing / fixing the heater let me know and I'll tell you what to do.
They commonly get their air intake a bit blocked by carpet fluff, or spiders webs if the air intake is under the floor. This gives a yellow flame. Also the spark ignition may be faulty which needs a new piezo igniter. The gas jet might get blocked, so you just replace it with a new jet - or if you are reeeeeeely clever you can prick the little hole with a very very fine needle.

No problem with my boiler thanks. Just always wondered how I was going to be able to work on it, should I ever need to.

Love my moho by the way. Fiat 2.8ltr 160hp engine and Alko chassis.  Had it from new and still haven't found anything I would prefer.

Its plated for 4 tonne, so I  guess the only reason to change it would be if I couldn't pass the 3 year medical.

I find the forum an interesting read, though this is the first time I've asked a question. Everyone is most helpful.  Appreciated

To work on the heater you remove the front cover and everything you need to work on is in front of you. If you are of the 'medical driving licence' sort of age, the most difficult part of working on the heater is getting up off the floor.

By comparison, we consider ourselves fortunate that the Truma boiler is entirely exposed from under fixed bed. However, feel the need to congratulate gassygassy on his most informative instruction with added ingenuity. If need be, hope this gives confidence for others to take on.

Informative but it makes me squirm when unqualified folk work on gas........

........they wouldn't have to if A/S put them in properly in the first place. I haven't sent this off to MMM for publication because I don't think they would dare publish it, and they wouldn't want to criticise one of their big advertisers.

I think anyone anxious about their competence wouldn't attempt such a job in the first place. They can of course get the work checked by a LPG qualified engineer before they turn the gas back on. An annual habitation check, if done properly would show up any faulty work. And.....as I found out after I got qualified and thought 'here I come world, I can install and fix boilers', there are a couple of years difference between a qualified GSR engineer and a competent GSR engineer. The irony is that after 30 years of being a competent, registered Corgi / GSR engineer, when you don't renew your membership because it costs well over £1000, you suddenly become incompetent.

Great post.

Ray

I found your post interesting. Unfortunately my Broadway is only year old and warranty has to be considered. Ever since new, we have been bedevilled with a hot "plastic electric smell" when using the blown air system. The van has been back to the factory twice with the problem persisting. Autosleepers assertion is that it is not their fault but a Truma design problem. They even tried re routing the duct pipes thinking it is back pressure causing the blower fan to over heat. I believe Truma changed the aluminium sheet pressed fan for a phenolic resin moulding. This creates a smell reminiscent of Salextrix model racing car hand controllers burning out! It is so strong we have to leave the van and ventilate it. Not pleasant during autumn and winter. Do other owners suffer similar experiences?

Its a common cause of complaint. My 2011 Malvern has a Trumatic fire floor mounted. From new, when the fire was set to hot there was a very acrid smell. I was told that the cause was hot air blowing over the vinyl that is bonded to the surface of the floor and on removing the front of the fire, I could see scorch marks on the floor. I cut up a silicon heat pad and covered the relevant area of floor, this reduced the smell considerably but did not totally eliminate it.

My previous van had an almost identical installation but the Trumatic was lifted about 3 inches above the floor by a plinth. That did not give off the smell.

Phoboff wrote:I found your post interesting. Unfortunately my Broadway is only year old and warranty has to be considered. Ever since new, we have been bedevilled with a hot "plastic electric smell" when using the blown air system. The van has been back to the factory twice with the problem persisting. Autosleepers assertion is that it is not their fault but a Truma design problem. They even tried re routing the duct pipes thinking it is back pressure causing the blower fan to over heat. I believe Truma changed the aluminium sheet pressed fan for a phenolic resin moulding. This creates a smell reminiscent of Salextrix model racing car hand controllers burning out! It is so strong we have to leave the van and ventilate it. Not pleasant during autumn and winter. Do other owners suffer similar experiences?

Not when using the space heating but often with the water heater

Our last Warwick suffered from the smell when the hot water was on. Our noses always told us when the water was heating. It seemed to be the insulation causing the smell and was apparently considered quite 'normal'.

Phoboff wrote:..........The van has been back to the factory twice with the problem persisting. Autosleepers assertion is that it is not their fault but a Truma design problem. ........

I think you should have a big fat bunch of documentation that came with the vehicle. If you look in amongst it I think you might find the Truma installation instructions - although you would never be expected to install it you still get the book. . . . . . ..I think you might have the installation diagram, I can't be sure. I know I have seen it somewhere and I can't at this moment find it on the internet.
If you can find the installation diagram clearly showing the inspection panel facing into the habitation area you can take it to A/S and show them and tell them to install it in accordance with Truma's instructions.

gassygassy wrote:I think anyone anxious about their competence wouldn't attempt such a job in the first place. They can of course get the work checked by a LPG qualified engineer before they turn the gas back on. An annual habitation check, if done properly would show up any faulty work. And.....as I found out after I got qualified and thought 'here I come world, I can install and fix boilers', there are a couple of years difference between a qualified GSR engineer and a competent GSR engineer. The irony is that after 30 years of being a competent, registered Corgi / GSR engineer, when you don't renew your membership because it costs well over £1000, you suddenly become incompetent.

I wouldn't certify anyone else's work. Be them competent or not. I have also been in the business for over 30 years and have always refused to do this. You know we get asked to do it regularly...... just not worth the hassle. Like you mentioned earlier..... you can work on your own installation but are still liable for prosecution if anything goes wrong and an injury or god forbid, worse happens...... competent or not.......

How do you take the front panel below the drawer off?

With some difficulty! Gently prise the caps off about 8 fixings around the edge of the panel and remove the screws that retain the panel. 4 screws secure the plastic vent. Also unscrew the 2 hot air vents from the panel. Then VERY carefully ease it out (you have of course already removed the drawer above).
You may break one of both of the vertical narrow ply strips that are alongside the drawer opening. Whether or not they break reinforce those strips with more ply glued behind before replacing. You may also need to do some minor chamfering of the rear edges of the panel to make replacement and later removal easier.. if you do rotate the unit you may need extra gas pipe, combustion flue pipe (two concentric tubes) and new hot air pipes to the vents.
Hope that helps.

Thank you. After removing one of the plastic caps, I can now see how to remove the screws. I originally thought they used the type of 'cam' type fittings used by IKEA furniture.