Automatic drain valve on new vans

New owners of a 2017 van upgrading from an older van (like me) should be aware that the Truma Combi boilers have a drain valve (nothing unusual there) that opens automatically when the temperature drops to 3@C.
I have only ever encountered manual drain valves previously and for some reason I never imagined a drain valve would be automated.

Last night was 2@C in Hampshire where I am :-)

After reading another thread, I went out to test out my heater blankets. Put the pump on and, after 10 minutes, I realised it was still running so I looked underneath to see water coming out near the boiler. I thought "oh no" it's a fault and started photographing and videoing in preparation for a warranty claim.
Now I realise the drain valve opened last night by itself.    

Or maybe I'm the only one who didn't know that

Also I have seen page 9-15 of the manual and tonight I even read it.

Not mentioned at handover?

And that's an improvement?   can it be over-ridden or disabled?

Les W wrote:And that's an improvement?   can it be over-ridden or disabled?

Better than having a damaged boiler or pipework because you forgot to drain it or the temperature fell unexpectedly when the boiler was full.

There is a lot of info out there about disabling it but is it worth the risk ?

When we are using the van in winter we keep the heating ticking over and have never had the drain valve activate but it us reassuring to know that it is there should we be withour heating for some reason or forget to drain the boiler.

Les W wrote:And that's an improvement?   can it be over-ridden or disabled?

It can easily be replaced by the manual type with the yellow lever.

What Quilter says is obviously good sense, but I have a rabid dislike of gadgets that do the thinking for me! I would personally prefer to be in control so we don't lose our water overnight (as many people have reported) and trust that the ancient memory will not fail when it comes to draining down.

[You must be registered and logged in to see this link.]

Its unlikely to activate if you are using the van as it needs to be 3 degrees at the valve for it to open. When you're in the van you are likely to have the temp higher than that so it won't open. Moral at this time off year is to drain system if not using it.

I think the auto valve is going to be fine. It is just the boiler so you don't lose much water so long as the pump is switched off.
And once it opens, it stays open until you manually close it even after temperature rises as it has today.
I just wanted to alert anyone who was not aware and avoid the uncomfortable 15 minutes I had  

In the winter, when away, we have the heating on a minimum of 15c day and night... Even if the taps on the site have frozen, the auto dump hasn't opened. In any event you can open or close the auto dump manually, but it does it for you if the temperature drops to a level where boiler damage is possible.. I think it a good system..

Moral of story and Confucius say "  READ YOUR A/S DESTRUCTION MANUAL ".  It was printed for you to read before you blow your van up. Sorry but I seriously have to laugh.

The frost control valve opens at 3c and can be closed when the temperature reaches 7c.  How did the van get so cold when you were using it?
PeteJ

In the opening post, it says he went out to check tank heaters so I assume he wasn't actually using it.

As our van is in storage, I'm a fan of the automatic drain which has activated right into June up here. Although the temperature is unlikely to drop enough at that time of year to cause damage, it's reassuring that the protection it there. Otherwise we would have to spend our time draining down every time we use the MH until we get into July. 

It should also be noted that getting the valve closed in cold weather can be a joy  . Not the first time I've been stuck under the seat with a hairdryer, trying to get the thing closed. That's even after driving to a site with the internal heaters on.

Askit wrote:Otherwise we would have to spend our time draining down every time we use the MH until we get into July. 

Logic for your climatic conditions seen and understood, but what do you mean by "spend our time"?

All the automatic gadget can do is open the tap. Flicking the yellow lever before you leave the van does exactly the same, and takes about three seconds. I can only speak from experience, but I've never had a problem closing it in cold weather.

Suggest you emigrate to England where it's warmer. (We are pretty tolerant of foreigners - I married one!!  )

Dave, when I said "spend our time" what I meant was having to drain each time we leave the van and then refill when we go off again. Our storage facility has good points and bad. The good is it's very secure and relatively cheap. The bad is it's a fair distance away, has no running water and in an valley area where local temperature can drop rapidly......even in a Scottish summer   

I do occasionally venture over the border to visit (my passport is right up to date    ) but the occasional cold snap is worth putting up with to remain this side of the border  

Fashing wrashing bloody automatic drain valve. I'm trying to fill the tank and boiler and EVERY FIVE MINUTES bloody thing kept dropping the water. Aghhhhhhh!!! Heating's on, sun is shining and I'm sweating cobblers now. Fair enough there was a deep frost last night but it's perfectly safe now. Is there an easy way to (temporarily) override the pop out switch thinggy ?! I'd be awfully grateful if you could.  
Cheers

First thought is to play the hair drier on the valve to warm it up.

I'm assuming you have pressed in the blue re-set button near the base and it keeps popping out?

Presumably you will not have turned the knob at the top?? In one position it holds in the blue reset button for normal use of the van. Turn it through 90 degrees and it releases the button to manually (deliberately) dump water. It needs to be turned to where the blue re-set button stays in when you press it in.

If you can't get it to work any other way you could try bracing something against the little blue button. If you can keep it pressed in it will hold the valve closed.

Gromit wrote:First thought is to play the hair drier on the valve to warm it up.

I'm assuming you have pressed in the blue button near the base ??? and it keeps popping out? Presumably you will not have turned the knob at the top??

Just had a look at ours (which is in a drawer in the garage . . . where it belongs!!!  ) and if yours is the same you could try bracing something against the little blue button. If you can keep it pressed in it will hold the valve closed.

Oh cheers for timely , good advice sir ...   . 
Yes ! hairdryer worked !!! and thanks for the tip about bracing the blue button in for future cold spells. 
Wife says to take your other advice too and in our next motorhome , the automatic valve will be left on the forecourt - where it belongs lol

Just added a bit more info to my post, but fortunately you didn't need it. Glad it's sorted, but it does sound as if your valve is dumping the water a bit prematurely.

As I've said before, I don't like gadgets that try to do my thinking for me!! 

It's very easy to replace the auto dump valve with one of these . . . . [You must be registered and logged in to see this link.] and IMHO worth 20 quid to be rid of the uncertainty whenever it goes a bit cold. Of course you do have to remember to flip the yellow lever when draining down the system in preparation for cold weather, or the hot water tank will not drain!!!!

Just been caught on this ourselves. Parked up and took so long to work out why the pump was running but no water coming out that we lost nearly all the little water I had put in the tank. 
As has been said previously it does help if you read the book! 
 I see that Truma have a heating element (part no. 70070-01) which will heat the valve once the boiler is on but would obviously still need the blue button pressed as well. 
Just wondering if anyone has one of these and if they feel it’s worth it.

I like our auto drain valve. I think its a useful precautionary device which protects the boiler. We do however, usually drain off completely between trips. I don't fancy using water which is weeks old, even for washing up, in warm weather bacteria can form in the systems pipework and in cold weather it can freeze. I do have the advantage of having the van on the drive, so before we go away, we can warm the interior for a while which prevents the valve from opening. In the knowledge that the valve can open, and indeed knowing that those parts not protected by the valve can freeze, if there is water in the van, we have the heating is on low anyway. In our previous caravan, we had a whale pump which didn't work after a very cold spell whilst it was in storage. That was a £50 mistake.

Most newer van owners would need to replace the drain valve with one of these:
[You must be registered and logged in to see this link.]

Question asked on the FB group. Is this the drain tap as it doesn't seem to do anything. I've never seen a drain tap like this. If it isn't a drain tap, what is it?

[You must be registered and logged in to see this link.]

Hi Paul
The pic is a spitting image of my manual drain valve for my water heater. Much preferred to the automatic gadget. But, for some reason this year it refused to drain. Likely it had an air lock. Filled the freshwater tank up fully, turned off all taps, switched water pump on for a short period and presto the water from the heater [now under pressure] started to flow to the ground and continued to do so when the pump was turned off.
Mel

Thanks Mel, I'll pass that on.

We used to have a Burstner MH some years ago which would dump the boiler water at 7c. We like others would clip a clothes peg around the valve to prevent it from dumping. This was only done if the temperature didn't drop too low.

Leighton.