How to replace UFH return pin valve

[shakeyjakey]

Hello,

I have UFH set up with a HIU in my flat.

My issue is that one zone (Bedroom 2) does not heat up. All other zones working and heating as expected.

Have checked the relevant thermostat, as well as the electrical actuator for the specific zone. Both look ok

Checked return pin valve - closed and stiff. Pulled pin up manually however still no heat (seemed odd) in bedroom 2 or on the flow pipe leading to zone from manifold. Pin also stays down when pushed in manually (no spring back)

My assumption is that the pin valve needs replacing...
1. Is this a sensible next step given above?
2. If so, how do I do it? I have tried a Hex socket but the blue actuator adapter connection wont let me get to the actual valve (gap not wide enough to take the socket). Pic attached

Cheers

 

[Timmy D]

Push it down/pull it up a few times to ensure it’s free. Check flow meter to ensure it’s not closed.

If that fails, isolate manifold. Depressurise, remove pin/actuator and see if it’s come apart inside manifold. Could possibly repair it.

 

[shakeyjakey]

Push it down/pull it up a few times to ensure it’s free. Check flow meter to ensure it’s not closed.

If that fails, isolate manifold. Depressurise, remove pin/actuator and see if it’s come apart inside manifold. Could possibly repair it

Thanks for the input @Timmy D.

I've pushed and pulled and the pin does move when I manually manipulate in this way with pliers.

How would you check a flow meter? I've observed the meter when the heating is on and it reads zero for the zone/pipe in question.

Have now isolated and depressurised. Could you advise how I get the pin/actuator out to see inside the manifold? I had assumed hex socked but the blue adapter ring stops me getting onto the valve to unscrew

 

[Timmy D]

It’s likely that the blue head adapter unscrews to give spanner access. Then unscrew it.

Have you got a pic of full manifold showing all flows and returns. Usually the flow meter is separate opposite the actuator and can be adjusted, but it looks like yours might be inline with the actuator. You usually twist them to change the flow. Yours may be set closed or stuck closed.

 

[shakeyjakey]

It’s likely that the blue head adapter unscrews to give spanner access. Then unscrew it.

Have you got a pic of full manifold showing all flows and returns. Usually the flow meter is separate opposite the actuator and can be adjusted, but it looks like yours might be inline with the actuator. You usually twist them to change the flow. Yours may be set closed or stuck closed.

@Timmy D
Indeed. Based on what I've seen online this may not be a standard install. I've previously tried to get at the flow meter but it seems easier said than done - looks like it's encased in metal..
Unfortunately twisting the blue plastic adapter doesn't seem to work. Also tried to lever it off with a flathead - it's on there pretty good
Pics attached

 

[Timmy D]

Get the blue head adapter off and unscrew the actuator.

There must be a way to adjust the flow. It’s either on the actuator (just looked at what I believe is the manufactures website, some of their actuator adjust this way, I don’t think yours do, pics from site attached).

Or undo the screwed cap on the below manifold on the corresponding loop and you may find an adjustment pin.

 

[shakeyjakey]

Get the blue head adapter off and unscrew the actuator.

There must be a way to adjust the flow. It’s either on the actuator (just looked at what I believe is the manufactures website, some of their actuator adjust this way, I don’t think yours do, pics from site attached).

Or undo the screwed cap on the below manifold on the corresponding loop and you may find an adjustment pin.

View attachment 81070View attachment 81071View attachment 81072

ok, cheers. Will have a look at that

Finally got the valve out. Looks intact - but should presumably move when you push the pin in?!

 

[Timmy D]

ok, cheers. Will have a look at that

Finally got the valve out. Looks intact - but should presumably move when you push the pin in?!

So you’re saying that the jumper/washer/internal piece doesn’t move when you push/pull the external pin?

Yes, they should move in unison.

 

[Basher]

As suggested by Timmy D, the flow adjustment is on the lower manifold under the screw caps, using a hex key:

 

[shakeyjakey]

So you’re saying that the jumper/washer/internal piece doesn’t move when you push/pull the external pin?

Yep, that's it. I've uploaded a video to illustrate for ref if anyone has a similar issue in the future.

Primary issue now resolved (no heat to zone).

Next job is to figure out how to increase the zone temperatures (the floors/rooms warm up but don't heat as much as I'd like them to)