Creating combined feed & vent

[Rhys_91]

Hi

I have blocked cold feed into the central heating. I've tried system cleaner and using mains pressure but I cant shift the blockage. Unfortunately I can't cut out the blocked piece of pipe either as it's below the tiled kitchen floor.

So the last option is can I combine the feed and vent? I've read online that some people are in favour and some against.
I've attached a picture of the pipes in the loft. The feed is the flat pipe and the vent it the one going out the roof.

Not sure why, but you'll see someone at somepoint has cut both pipes and rejoined them.
So my question is, on the feed pipe where the join is, can I cap the old pipe and then simply make a T connection to the vent pipe to connect them?
Can this be done simply using plastic pipe and push fit fittings?

Thanks for any help.

 

[picasso]

Yes you can connect the feed into the vent as long as the vent is 22mm all the way down and the boiler has a overheat stat.

 

[Rhys_91]

It's in the loft. It's just infront of that big pile of insulation that I moved so I could take a picture of the pipes.

 

[picasso]

Hi yes I realised when you said vent went out on to roof.

 

[Rhys_91]

Thank you!
Just checked the boiler manual (glowworm micron 50ff) and it does say that it has a safety overheat and I actually just noticed that combined feed and vent is mentioned in the manual as allowed.

I take it it really is just as simple as capping the blocked pipe and joining the 15mm to a tee in the 22mm vent?

 

[picasso]

Yes as simple as that.

 

[Rhys_91]

Just a quick follow up.

Connected the two pipes together this evening and it works perfectly. First time since owing the house that the system can fill itself up!

Thanks again Picasso.

 

[picasso]

Your welcome.