Drain down UFH

[trevorbayliss]

I need to move one of the 22mm pipes feeding the UFH manifold. Extension means i need a little more space where this pipe is currently so moving it 10cm to the right.

This means i need to drain down. The 22mm pipe comes down from the boiler and so water in this pipe is separate from the rest of the boiler radiator system due to the automatic gate valves under the boiler for the UFH.

So the whole system doesn't need a drain down just the UFH section.

I haven't drained down this before so wondered if i just open up the drain valve on the manifold and that is it, or do i do something else ?

Do i need to be worried about air entering the UFH system as well ?

 

[dilalio]

Well, depending on the layout of your property and where the UFH is installed, it should be the lowest point of the system and will remain filled when draining. If its above the manifold then you should have some way of isolating the manifold via built in service valves and even a manual or automatic air vent. If not, you could always introduce these to the modified flow and returns to the boiler when carrying out the work. There are always methods for purging the UFH - check out the manufacturers tech data.

 

[trevorbayliss]

Yes it is lower than the manifold and so will not drain.

So really all I have to worry about is the water in the pipe from the boiler gate valve to the manifold

 

[dilalio]

Yes it is lower than the manifold and so will not drain.

So really all I have to worry about is the water in the pipe from the boiler gate valve to the manifold

Is there an AAV on the manifold?

 

[trevorbayliss]

I don't think there is.

I have taken a photo of the manifold and the 22mm pipe higher up which i want to move to the right a bit more.

 

[dilalio]

There are two radiator type air vents on the right hand side above the drain cocks and you can also vent from the pump bleed screw.

 

[trevorbayliss]

Ok, great. I was aware of the bleed vents on the drain off points. Thanks for help.