central heating Y valve

[sotal]

I can't get my head round this one... probably me just being simple!


I think the Y Valve is broken but everything seems to be working!

We have a conventional boiler system, boiler in the garage, cylinder in the middle of the house in the airing cupboard.

If we put the heating on then the radiators heat up nicely, if we put the hot water on then the hot water heats up perfectly.

Putting the hot water on doesn't heat the radiators up, and I presume that putting the heating on doesn't heat the water up (but haven't tested this)

So it doesn't seem like there is any fault! but I'm sure the metal lever on the side used to move by itself as you went between hot water and heating (or both). The metal lever now never moves, it just stays at the left, I can move it and it feels very easy to move and kind of hooks on at the right but then the heating doesn't seem to work.

Have I actually got a fault or is this correct? Is there some way to prove a fault?

I believe it's a Danfoss 2 port valve with removable head

 

[kevplumb]

View media item 111482 port



View media item 11149
3 port

Y valve would suggest a 3 port

which is it

 

[sotal]

Sorry me being thick and thinking it has 2 outputs, so would be 2 port.

It is indeed a 3 port.

It's a Danfoss HSV3 3 port Valve

 

[Boilerman2]

If it is working leave it alone!! you'll know when it's broken!

 

[sotal]

I'm pretty sure it's not working correctly, but we haven't really fully started using the heating yet for this winter. We just do the occasional 1 hour boost.

Anyway I was having a bit of a test last night.

I put the CH on for 1 hour, I could hear something happen and the pump kicked in.

I left it for 5 minutes and confirmed the radiators were getting warm.

I then came back and put the hot water on and turned the cylinder stat up to make sure it called for water.

I could hear the 3 port valve move (but the lever didn't move)

I left it for a minute or two, then I switched the hot water off, at this point the 3 port valve didn't make any noise and the pump switched off. The CH was still set to be on and the room stat was still calling for heat.

I tried pressing a few things like switching the CH off then on again but nothing happened. I switched the HW on and the pump kicked back in, but then switching it off again the pump stopped.

I ended up moving the lever across to MAN, this kicked the pump back in again with only CH selected, once it was running I moved the lever back to AUTO and it carried on running.

Any ideas what would be up with it?

It is a removable head - is it likely I just need to replace the head?

 

[sotal]

Any clues on this can anyone give advice as to what the fault would be?

My next course of action was going to be to take the head off and have a look for anything obvious

 

[D_Hailsham]

Read Mid-position valve working and Diagnostics.

It contains detailed testing information.

 

[ChrisR]

The wiring's probably wrong. It's often wrong!

 

[sotal]

It used to work fine!

We did have a new boiler in spring last year (so towards the end of using heating) They didn't touch anything in the airing cupboard though, they just replaced the boiler - could they have messed anything up from there?

The boiler is in the garage and just has a few wires going to it.

 

[D_Hailsham]

We did have a new boiler in spring last year

What make/exact model was the old boiler?
What make/exact model is the new boiler?