Odd fill / drain valve on manifold

hobblewash · Dec 8, 2020

Hi there - I think I have an airlock in my UFH, and I need to flush the system to get it out. I've watched countless videos on how to do it which seems relatively straightforward, but what I can't figure out is the drain/return ports. They don't seem to have any valves to open/close them, which seems odd. Does anyone have any clues how these are supposed to work.

I realise this is probably a dumb question, so thanks in adance for your help 🙂

Tow pictures below. One of the fill / drain port and the other of the manifold.

Thanks!

Timmy D · Dec 9, 2020

Why do you think you have an airlock?

steadyon · Dec 9, 2020

1. UFH not my speciality, but I would guess the lower part with the hose attachment rings unscrews. Why else have the knurling on the part just below the body?
2. Give it a try, but very gently in case it is some sort of bayonet fitting, although I doubt it.

hobblewash · Dec 9, 2020

Timmy D said:
Why do you think you have an airlock?

One zone never gets hot, just a process of elimination. The guys who did the extension a few years ago extended a downstairs zone to a new upstairs room which has never got hot. Trying to figure out what the issue is.

thanks for your responses

exedon2 · Dec 9, 2020

When you say a downstairs zone was extended upstairs how was this done? The new circuit connect directly to manifold?

hobblewash · Dec 9, 2020

exedon2 said:
When you say a downstairs zone was extended upstairs how was this done? The new circuit connect directly to manifold?

To be honest I'm not entirely sure. They said at the time they 'extended' an existing zone to save digging up the floor. Thanks to your help on here, I've not flushed the system, I don't think there was an airlock in there afterall. Must be something else, but trying to reverse engineer underfloor when you don't know where the pipes run is a long winded process of elimination and learning on the job!

Timmy D · Dec 9, 2020

Can you take the actuator head off of the effected zone and check that the pin moves freely?

hobblewash · Dec 10, 2020

Timmy D said:
Can you take the actuator head off of the effected zone and check that the pin moves freely?

Yes, it seems to work fine. Could it be that the pump is underpowered to 'push' the water upstairs? Be gentle if this is a stupid question 🙂

Ben-gee · Dec 10, 2020

If you’re on good terms, why not contact the guys who did the work and ask them exactly what they did.

Obviously in a friendly manner!

Then maybe pay them to come and sort out your current problem?

exedon2 · Dec 10, 2020

So to be clear is the manifold downstairs and the problem zone upstairs? any of downstairs zones a problem?

hobblewash · Dec 10, 2020

Ben-gee said:
If you’re on good terms, why not contact the guys who did the work and ask them exactly what they did.

Obviously in a friendly manner!

Then maybe pay them to come and sort out your current problem?

They’re not a going concern anymore unfortunately, so it’s down to me to try and sort it. Every other engineer in the area seems to be busy into next year.