Boiler emptying itself - Hymer B544 (1 Viewer)

[3874helen]

***sorry I'm new here and I posted a message to forum but not under Tech/Mech General and have been recommended to post my query in here too***

Hello all,

This is my first time on a forum, so I'm sorry if I'm doing it wrong or typing in the wrong place. It looks interesting the information about Rallies and other peoples travels. I can't wait to read more! At the moment though...I’m just wondering if there’s anyone with the same or similar model motorhome who might be able to offer some advice.

We have just bought our first Hymer, it’s a B544 year 2000 left hand drive with a Traumatic C system with boiler and heating via gas. I filled the water tanks today and then opened the hot water taps in the bathroom and kitchen to fill the boiler. I left the taps running until all of the air appeared to have come out of the taps and then turned them off and turned on the hot water boiler on the control panel (on the side, exterior of the wardrobe. The boiler is in the base of the wardrobe.)


The yellow light came on (on the panel) as indicated in the handbook and then when the yellow light went off (I checked and it had after about 20 minutes) I ran the hot water…it let a little water out for about a second and then spluttered and was forcing air out all over again for quite a few minutes. After that the water ran freely….but it was completely cold. The yellow light came back on the control panel and so I thought I’ll leave it for 50 minutes, maybe I’d not given it enough time (being a complete novice). I came back again and the exact same thing happened.

I felt the boiler and it was really warm and started to get concerned as I’d heard horror stories about boilers burning dry. The little red valve (for emptying the boiler) was up as per the previous owners instructions and the manuel (we’ve also tried this after we bought it when we brought it home to drain it for the cold weather and it did indeed empty the tank.) I then pressed the little red valve down to see it there was any water in it as I couldn’t understand how the boiler was warm but the water was completely cold. It was empty, it made some sighing and gulping noises but no water came out at all! So now I’m worried that I’ve killed my boiler but also where the water is going and why it is not staying in the boiler. I’ve emptied the whole system to see if it was an air lock and started again. But again the same thing happened (I opened the hot water tap to fill the tank…however didn’t switch the boiler on this time). When I came back the boiler had drained itself again.

So this is all that I know, the boiler seems to be emptying itself off straight away into the grey waste tank (as this was empty and had water in it after I came back having left it with the boiler full…I had the plugs in the sinks when running the air/water through to fill the tank so there was no water going through from these). Also there are three little pipes under the motorhome (under where the boiler is, one of them is where water would normally come out if you drain the boiler) and once I’ve filled the boiler….I can hear it slurping/sucking up air into one of these tubes. I wondered if there was another valve that had come open (we haven’t opened any others to my knowledge, I’ve looked around the boiler and can’t find any other valves apart from the main red one either).

Any advice would be much appreciated, many thanks in advance Helen

PS (A few people have mentioned it could be the "t-piece" that has broken, if so, would that fill the boiler with air and send the water to the grey water tank?)

 

[Figaro]

OK, your in no danger of burning your boiler dry, it can be used for heating without filling with water.
Firstly make sure the auto frost protection dump valve is in up position. It`s usually sited next to the boiler.
Then there will be 2 drain valves for h & c water, mine are next to the grey waste dump valve in external locker, one will be red the other may be clear or blue, turn these off.
Refill the water tank and rune all taps until all air is released, this may take some time.
Make sure gas is on and turn on boiler. You should get warm water within half an hour.
Have you got blown warm air coming out ok ?

Have you got boiler instructions ?
The water from the boiler can`t get to the grey tank without going through the taps into the sink and down the plughole
Come back if you still have problems.

Oh, and welcome to the forum
Chris

Edit : don`t forget to drain again afterward if not in use, to protect from frost

 

[3874helen]

Hi Chris, thanks for your advice! It's a bit dark now to go looking for the pipes, but I'm going to have a good old nosey around tomorrow and find where these two pipes connect to a valve, I never thought to look outside. The blown air works fine but I turned it onto just water heating after checking it was working. I've got the boiler instructions, I had a good read of them earlier but that was before I got responses on here, so maybe I might understand them a little better now. Thanks again, everyone has been so helpful, what a fab group.

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[Figaro]

Sounds like the problem might be those two drain valves that are open, did you see any water running out underneath ?

Great choice of motorhome by the way
You won`t go far wrong with a Hymer

let us know tomorrow if you get it sorted

Chris

 

[andy63]

. The little red valve (for emptying the boiler) was up as per the previous owners instructions

If that's the boiler dump valve and it's similar to mine then if the lever is UP that's in the dump /drain position and the boiler will empty.. but you would see the water draining under the van..
Unless you are certain try the lever down and fill the boiler or check for water appearing under van...
Andy.

 

[3874helen]

I hope its something simple like that (well simple once I find them ) I didn't see any water running out underneath... But its got to have gone somewhere
Will update you tomorrow thanks again

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[XRN]

If that's the boiler dump valve and it's similar to mine then if the lever is UP that's in the dump /drain position and the boiler will empty.. but you would see the water draining under the van..
Unless you are certain try the lever down and fill the boiler or check for water appearing under van...
Andy.

On Hymers, when the red valve is pulled up drain valve is closed retaining the water in the boiler, it drops down when the frost stat operates and the solenoid opens the valve to drain the boiler.
You can keep this drain valve closed in cold conditions by pulling it up and sticking a clothes peg on it to stop it dropping. Remember to take it off though if it is going to be frosty.
Chris's comments are correct and should help you further. As you have posted twice on this subject you may want to close one post so all replies go to one.

 

[3874helen]

Thanks yes I definately will, not sure how to close it, first time in a forum today for me, I will have a look now. Cheers Helen

 

[TUCANO]

OK, your in no danger of burning your boiler dry, it can be used for heating without filling with water.
Firstly make sure the auto frost protection dump valve is in up position. It`s usually sited next to the boiler.
Then there will be 2 drain valves for h & c water, mine are next to the grey waste dump valve in external locker, one will be red the other may be clear or blue, turn these off.
Refill the water tank and rune all taps until all air is released, this may take some time.
Make sure gas is on and turn on boiler. You should get warm water within half an hour.
Have you got blown warm air coming out ok ?

Have you got boiler instructions ?
The water from the boiler can`t get to the grey tank without going through the taps into the sink and down the plughole
Come back if you still have problems.

Oh, and welcome to the forum
Chris

Edit : don`t forget to drain again afterward if not in use, to protect from frost

Helen,
A warm welcome to the forum, even warmer when you sort your little trouble out

Figaro, owning a Hymer myself I am a little puzzled, easily done though, by the comment in the first line of your reply to Helen in which you state that the boiler can be used for heating without filling with water, is that correct thanks.
Norman.

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[3874helen]

Lovely thanks people, it was about 15c outside yesterday when I was having the issues and I have an oil radiator in there from the house so it was quite toasty. The red valve stayed up the whole time even though the pipes outside were sucking air back in. I'll have another look this morning and hopefully it'll be something simple.

 

[3874helen]

Morning all, so ive been out messing this morning, the camper is well above 8c. I filled the boiler, left the taps running hot and cold for a good 5 minutes with the shower head in the air. I found the valves under the kitchen cupboard and they were totally tight.

No sooner had I turned off the tap could I hear the boiler sucking back in air. I went outside and sure enough its sucking the air back in from one of these (photo attached) three pipes.

So if I've understand correctly, does it sound like its the "t piece" that's sucking the air back into the boiler and forcing the water back into the fresh water tanks? There is no water that i can see coming out underneath anywhere.

Thanks ever so much for all of your help, It's been brilliant, like a mini get to know your motorhome lesson with a bit of plumbing thrown in

 

[3874helen]

PS once I get the taps running on hot (and running for a long time to get rid of the air) I go back 5 minutes later and have to start the whole process again, literally you can hear the tank filling all over again.

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[wanderer]

Just a suggestion that the previous owner has fitted a new pump in the fresh water tank without a non returning valve and the water is being returned to the fresh water tank after heating , you can check this by feeling the temperature of the water in the tank it will be slightly warm depending how much water in the tank.

 

[Figaro]

Figaro, owning a Hymer myself I am a little puzzled, easily done though, by the comment in the first line of your reply to Helen in which you state that the boiler can be used for heating without filling with water, is that correct thanks.

You'd better check you manual but as far as I know they can all be run without water.

To the OP I'm afraid I'm at the limit of my technical knowledge now and I've no idea why the boiler would be sucking air in.
I'm sure others will be able to advise.
Hope you get it sorted
Chris

 

[SIFTA SAM]

I agree that it may be a defective Non Return Valve allowing water back into the Freshwater tank via the Pump?
Will send you a link by PM

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[3874helen]

Aww brilliant thanks!

 

[3874helen]

Hi all, thanks for all of the advice, the good news is we've literally just finished putting on a new non return valve.....
And it works!!!!
I'm soo happy! So where to go haha, think we're going to head off tomorrow for our first little road trip for a week (we live in France nowadays, so somewhere towards the coast I think).
I just want to say thanks for all of your advice, it has been brilliant, thanks again Helen

 

[rally58man]

All I have a 1992 hymer 534 but have no paperwork is manuals are there any on here or where to get them from cheers kev.

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[XRN]

@rally58man my instructions may be of use but mine is a B680 year 2000 model.

 

[rally58man]

Thanks peeps anything will help