Truma boiler draining

[Harrytherid]

Truma boiler C403-E-18059381

I have a Truma boiler in my MH which has always worked perfectly except for just now. I turned the boiler and heating off when the boiler was full of hot water and it immediately began to drain. My understanding is that it only drained when the water got down to 2 degrees, Centigrade, I imagine.

What is wrong with it? I in order to get it filled from cold I had wedged the button in the up position and on switching off I removed that wedge to allow the button to do its thing and it immediately drained all the hot water. Any ideas? What am I missing? How do I fix it?

 

[Fisherman]

Sounds like your frost valve may be faulty.
As far as I know they don't operate when the boiler is in use, hence why it drains your water when you switch it of.
The thermostat in the frost valve may be faulty sending power to the relay and operating the switch.
I would leave the water on but set to 40C to avoid this, then replace or do away with the frost valve.
Remember the temperature has to be above 7C before you can reset it.

 

[witzend]

Truma boiler C403-E-18059381

I have a Truma boiler in my MH which has always worked perfectly except for just now. I turned the boiler and heating off when the boiler was full of hot water and it immediately began to drain. My understanding is that it only drained when the water got down to 2 degrees, Centigrade, I imagine.

What is wrong with it? I in order to get it filled from cold I had wedged the button in the up position and on switching off I removed that wedge to allow the button to do its thing and it immediately drained all the hot water. Any ideas? What am I missing? How do I fix it?

Mine has always been like that but I know it should work as You say. I lift the drain and put a clothes peg on it only removing it when I want it to drain. Witz

 

[Harrytherid]

Thanks lads. I would do as you say Witz but my memory is the problem there. Rather unsafe if one forgets to remove the wedge. I should feel safer replacing the faulty part but from past experience of Truma one would expect it to be rather expensive. I will look on eBay. and report back. Regards, Harry

 

[Harrytherid]

Only one available on eBay so far as I can find and it is £79.99 so yet another job for wife. Remining me to release the wedge.

 

[campervanannie]

Thanks lads. I would do as you say Witz but my memory is the problem there. Rather unsafe if one forgets to remove the wedge. I should feel safer replacing the faulty part but from past experience of Truma one would expect it to be rather expensive. I will look on eBay. and report back. Regards, Harry

I don’t think it’s faulty I think if you turn off your 12v supply they drain that’s what mine did in the last van and does in this van but I do have a fishing hook through the red button with fishing line so I can fasten it up while I refil the boiler during cold weather otherwise it drains as fast as I fill it.

 

[Harrytherid]

Maybe you are right Annie. I will experiment. It did not do that in the past but there may be other differences that I have not noticed. My "fishing hook" is a thin plastic two pronged curved fork on a thin cable tie to stop it from getting lost which is slipped in under the button. Works a treat but my memory does not. Apparently it is not Alzheimer's, just old age, they tell me.

 

[Fisherman]

I don’t think it’s faulty I think if you turn off your 12v supply they drain that’s what mine did in the last van and does in this van but I do have a fishing hook through the red button with fishing line so I can fasten it up while I refil the boiler during cold weather otherwise it drains as fast as I fill it.

Annie, this will happen if your valve has opened due to the temp dropping to 3C. You cannot reset the switch until the van goes above 7C. The mechanism is controlled by a thermostat which switches the valve to the open position. It makes sense that if you remove the 12v supply the valve would open for safety reasons. This indicates that the power keeps the relay switch in such a position as to keep valve closed, removing the power mimics the thermostat in opening the valve. But Harry’s valve was opening with the 12v supply intact, whilst it was turned off.
What Harry could try would be to try to heat the switch with a hairdryer that may reset the thermostat temporarily, but in my experience once a thermostat becomes faulty, they need replacing. Sadly as usual Truma charge ridicules prices for these things, I have seen them from £80 to over £200, if you’re daft enough to pay that.

 

[Geek]

The old valves used to need. 12v power to stay closed. Never ones don't.

They are all meant to open at 3 degrees or colder, You're not supposed to be able to close then unless it is 7 degrees or warmer. Just put the heating on for an hour or so first.

It's very foolish to peg them closed. Frost in the heater is a £3000+ bill. If you want to keep water in, keep the temperature up.

 

[Fisherman]

The old valves used to need. 12v power to stay closed. Never ones don't.

They are all meant to open at 3 degrees or colder, You're not supposed to be able to close then unless it is 7 degrees or warmer. Just put the heating on for an hour or so first.

It's very foolish to peg them closed. Frost in the heater is a £3000+ bill. If you want to keep water in, keep the temperature up.

Yes geek I agree, it’s a safety device to avoid damaging your boiler.

 

[Sharon the Cat]

Drove us mad on our old van. We lost water everywhere we went. Clothes peg was our saviour, that and a good memory for never leaving water in the system if we weren't using the van in cold weather.

 

[witzend]

Only one available on eBay so far as I can find and it is £79.99 so yet another job for wife. Remining me to release the wedge.

There are manual ones on there for half of that but with them You still need a good memory. But I'd rather rely on my memory than a auto valve

 

[witzend]

It's very foolish to peg them closed.

The New ones are supplied with a manual drain valve with the old auto You had to keep checking if it had worked if it hadn't You could still get a hugh bill

 

[Harrytherid]

You are not going to get ice in the boiler at a temperature above one decree let alone three. Seems overkill. I shall stick to my wedge override and my wife's memory which is pretty good. It is normally left open unless we are in residence during which time the temperature is unlikely to go below 10 degrees. I would get loud high pitched noises from Julie if it did.