Broadway winter water dump valve question

I seem to recall from Grammar-School Physics lessons (I slept through most of it, so this may be rubbish) that as the temperature drops, water starts to expand at 4 degrees Celsius- presumably the dump valve opens above that temp as a margin of error. Truma are very specific that no warranty claims will be entertained for freezing of units, even if no dump valve is fitted. That could be a bit of a trauma.....

See: I was not dreaming: http://www.iapws.org/faq1/freeze.htm

I'm pretty sure the heating element is really only designed to enable you to close the valve at lower temperatures when the boiler is powered so you can fill the system. I never thought of it keeping the valve closed when you are using the van, we always have heating on through the winter. When the vans parked up outside it's on EHU and the heater thermostat set at 10-12 degrees. This keeps heat in the water and valve to stop it opening. Before we travel, we always set the water to heat up and it stays warm for hours, so no worries about losing water as we travel.
Last week, the temp overnight was around -2 and I switched on the water tank heaters ( fitted earlier this year, from CAK Tanks) and I finally got to see that they worked!
Van is at the dealers at the moment having its Hab check.  I left water in the system, hope the dump valve hasn't opened!
I'm collecting it shortly.
Allan
Ps, Bertie B. I have the tank heaters wired into the Sargent panel, so, I just realised they turn off when I start the van.  I'll have to put in some override switches so we can run the heaters when the vans moving

ajrm wrote:I'm pretty sure the heating element is really only designed to enable you to close the valve at lower temperatures when the boiler is powered so you can fill the system. I never thought of it keeping the valve closed when you are using the van, we always have heating on through the winter. When the vans parked up outside it's on EHU and the heater thermostat set at 10-12 degrees. This keeps heat in the water and valve to stop it opening. Before we travel, we always set the water to heat up and it stays warm for hours, so no worries about losing water as we travel.
Last week, the temp overnight was around -2 and I switched on the water tank heaters ( fitted earlier this year, from CAK Tanks) and I finally got to see that they worked!
Van is at the dealers at the moment having its Hab check.  I left water in the system, hope the dump valve hasn't opened!
I'm collecting it shortly.
Allan
Ps, Bertie B. I have the tank heaters wired into the Sargent panel, so, I just realised they turn off when I start the van.  I'll have to put in some override switches so we can run the heaters when the vans moving

aj, Many thanks for that, it never occurred to me though it should have done. Apart from the obvious reason of cost (and the National Caravan Council) why can't British vans be built to weather a 'mild' coldish snap without all sorts of work rounds and much gnashing of teeth?

That is a very good point as it 'would' make sense for the tank heaters to be running of the vehicle 12v supply while underway. Perhaps a feed cold be taken from the 12v fridge supply as long as the wiring/fuses could take the load , all automatic then. OR Could always use the fridge supply to trigger a relay to the heaters?

Cruising Comet wrote:The dump valve on our Broadway opens prematurely in my opinion... 

.........Even with the heating on and cosy inside the Broadway it's opened and dumped the water, therefore I'm guessing there must be a temp probe externally?

Thats a worrying experience, where is the dump valve located? Ours is right next to the Truma boiler so with the heating on, it keeps the valve warm and prevents dumping. We've been out in temps as low as about -10 and never had a problem with ours.
Allan

Thanks again to all who contributed. We have watched with interest and we have many things to think about.

We're now safely down in warmer climes; it was quite mild on the way so no aires were wet and, more concerning,  we did not leave a huge pool of water on the car deck of the boat either.  The first aire we used in Spain had the water switched off so it would have been an embarrassment to arrive empty.

Q

Quilter wrote:Thanks again to all who contributed. We have watched with interest and we have many things to think about.

We're now safely down in warmer climes; it was quite mild on the way so no aires were wet and, more concerning,  we did not leave a huge pool of water on the car deck of the boat either.  The first aire we used in Spain had the water switched off so it would have been an embarrassment to arrive empty.

Q

Q You lucky dog, not very jealous! Have a great time and a 'warm/hot' Christmas.

Please don't shout at me when I tell you what I did.  On the Neuvo the dump valve is not in the same place as the Truma so if you have a cold van you can't get it to reset until warm.  If you put a large cable tie round the whole unit, push the little blue pop out in and tighten the zipper up over it then it will allow you to get the water system filled and operational.
Then with the heating on and area warmed up (which it will due to the two heating duct hoses) you will find that you can push the pop out valve in the extra 0.5mm and it will latch.  At this point slide the cable tie down out of the way to restore your 'protection' but leave it in place for future use.

grantcoghill wrote:Please don't shout at me when I tell you what I did.  On the Neuvo the dump valve is not in the same place as the Truma so if you have a cold van you can't get it to reset until warm.  If you put a large cable tie round the whole unit, push the little blue pop out in and tighten the zipper up over it then it will allow you to get the water system filled and operational.
Then with the heating on and area warmed up (which it will due to the two heating duct hoses) you will find that you can push the pop out valve in the extra 0.5mm and it will latch.  At this point slide the cable tie down out of the way to restore your 'protection' but leave it in place for future use.

 welcome to the forum grantcoghill , and thanks for the tip.

John.

grantcoghill wrote:Please don't shout at me when I tell you what I did.  On the Neuvo the dump valve is not in the same place as the Truma so if you have a cold van you can't get it to reset until warm.  If you put a large cable tie round the whole unit, push the little blue pop out in and tighten the zipper up over it then it will allow you to get the water system filled and operational.
Then with the heating on and area warmed up (which it will due to the two heating duct hoses) you will find that you can push the pop out valve in the extra 0.5mm and it will latch.  At this point slide the cable tie down out of the way to restore your 'protection' but leave it in place for future use.

As John said in the previous post..........Welcome and thanks for the tip.................why should we be thinking of work-rounds on £60k vans?
To all who may read. Please don't tell me about the multitudinous benefits of slavishly following the edicts of the National CARAVAN Council.....................I won't believe you

This is a bit of a bump but on the OP's subject so valid I think. 
Having read and digested this thread I decided to get the dump valve heater element fitted on our Broadway which is about to be built. The response from Autosleepers was as follows (repeated verbatim):-

'we have no knowledge of this part (Truma Dump valve Heating Element part no 700070-01) and can only find reference to it in their spares catalogue, it appears to be an off the shelf item which plugs into the heater and only works with the system only working on mains electric, we are reluctant to fit as it may give us problems with the dump valve not cleansing the system at 3deg therefore suggest you advise the customer to arrange supply as a retro fit item.'


Interesting, and leaves me yet again with the feeling that maybe I've made an error going for an A/S van and expecting to be able to use it ALL YEAR!

Bertie Bassett wrote:
Interesting, and leaves me yet again with the feeling that maybe I've made an error going for an A/S van and expecting to be able to use it ALL YEAR!

Surely if you want to use it all year round, you've ordered the winter pack which includes tank heaters.

Paulmold wrote:

Bertie Bassett wrote:
Interesting, and leaves me yet again with the feeling that maybe I've made an error going for an A/S van and expecting to be able to use it ALL YEAR!

Surely if you want to use it all year round, you've ordered the winter pack which includes tank heaters.

Indeed we have but these only work when connected to EHU, which sadly is not on when travelling (and we travel in Northerly climes). I'm not a caravanner who fills on arrival at a site, often we won't be over-nighting at a site.............and we travel with water in the tanks preheated before departure in the Truma. I don't want that preheated water spewed all over the road because cold air is entering the many (necessary) vents at 55mph! It's appears simple for foreign manufacturers why not for AS?

I now understand your concerns. With 5 dealers in Germany now, they must be supplying something suitable for those buyers who don't have far to go to much colder climes.

Paulmold wrote:I now understand your concerns. With 5 dealers in Germany now, they must be supplying something suitable for those buyers who don't have far to go to much colder climes.

Having lived in Paderborn for 3 years I can attest to regular periods of minus 10 and below in Germany so agree with that Paul.There is also a dealership in Sweden. Whilst the set up runs off the 12v the amperage is sufficient to drain any battery on a reasonably balmy night. Why it needs to raise the fresh water temp to 18 degrees C is anyone's guess. However like a number of others I'm going to have a pair of CakTanks 12v heating probes retro fitted and wired separately from the Sergeant unit so they can be used on the move. So many of my acquaintances who winter travel and camp off site buy 'foreign' rather than Brit simply because the arcane NCC rules switch off all power preventing the habitation heating to be used on the move. If Laika, Pilote, and all the German makes do it 'safely' and have been for a number of years then British motorhome manufacturers are simply going to have to bite the bullet and bin the NCC accreditation which whilst I'm sure it is wonderful for caravans doesn't actually meet 21st century motorhome requirements. (Rant over!!)  Phew that was Goooood!

Bertie Bassett wrote: 
The response from Autosleepers was as follows (repeated verbatim):-

'we have no knowledge of this part (Truma Dump valve Heating Element part no 700070-01) and can only find reference to it in their spares catalogue, it appears to be an off the shelf item which plugs into the heater and only works with the system only working on mains electric, we are reluctant to fit as it may give us problems with the dump valve not cleansing the system at 3deg therefore suggest you advise the customer to arrange supply as a retro fit item.'

Bertie, 
I can assure you that it is in the A/S manual - in black and white!! 

In my case its clearly mentioned in section 9 page 10 of my A/S owners manual, so someone at A/S must be aware of it - after all they wrote it - or did they? 
Sounds like its a case of "can't be asked"!

Its very easy to fit yourself or get your dealer to fit it for you.

Its a bona-fide Truma part.

Liam

Liam wrote:

Bertie Bassett wrote: 
The response from Autosleepers was as follows (repeated verbatim):-

'we have no knowledge of this part (Truma Dump valve Heating Element part no 700070-01) and can only find reference to it in their spares catalogue, it appears to be an off the shelf item which plugs into the heater and only works with the system only working on mains electric, we are reluctant to fit as it may give us problems with the dump valve not cleansing the system at 3deg therefore suggest you advise the customer to arrange supply as a retro fit item.'

Bertie, 
I can assure you that it is in the A/S manual - in black and white!! 

In my case its clearly mentioned in section 9 page 10 of my A/S owners manual, so someone at A/S must be aware of it - after all they wrote it - or did they? 
Sounds like its a case of "can't be asked"!



Its very easy to fit yourself or get your dealer to fit it for you.

Its a bona-fide Truma part.

Liam

Liam, Can't thank you enough for that bit of info ............................your ''can't be asked'' bit spot on too. I have the name of the individual who sent the email......so I'm now going to follow it up. I'm glad that this has all come up though as we requested and have now received an AS order acknowledgement which has missed off a number of specified items that we (and our dealer) requested. Oh dear they really don't seem to want our business do they.

It WILL be worth the hassle in the end as they really are brilliant motorhomes  
What is it they say 'no pain no gain' ha ha.

Jaytee wrote:It WILL be worth the hassle in the end as they really are brilliant motorhomes  
What is it they say 'no pain no gain' ha ha.

True, we had a Duetto for years and were very happy with it. Funny, but that info Liam gave me caused a number of red faces ref the email claiming that AS had no idea about the truma dump valve part! Knock on is I now have more detail than I could possibly want..................and it's all correct! Great having a first class dealer who knows us as we know him............ar*e kicking by dealers on customers behalf shouldn't be required though. Can't wait to pick the van up and get mobile!