Blocked heating pipes on microbore

[jamscunny]

Been to have a look at a job in a big house thats been done in microbore. 3 radiators dont work that are situated in different ends of the house. The unvented cylinder is situated near the top of the stairs. I took up a hatch close to the cylinder hoping to find a manifold. it reduces from 22mm, then branches off to microbore along the way. The floors are tiled fitted carpets etc. so i dont want to go hunting for a blockage. I wont powerflush. I was wondering if any one has tried using a schrader valve connected to 1/2". Connect it to the leg of the radiator thats blocked and pump to 3/4 bar? Surely this would dislodge the blockage without causing more problems?

cheers for any input

 

[slapper]

Youll more than likely end up with repipe I,m afraid. Only way round it

 

[FiremanT]

Youll more than likely end up with repipe I,m afraid. Only way round it

I've successfully PF'd several Microbre systems with circulation problems.
But you won't do it in the 80 minutes that some guys seem to spend on a PF

 

[sooey]

Have you seen these chemical dosing thingios that Kamco do?

http://www.kamco.co.uk/IK6.html

You can use them for pressuring a rad and sending a surge of pressure back towards the blockage, trouble is you might just push any cr*p back into the manifold and block that, if you can get some circulation going though you can hit it with some x800.
It's only a glorified garden sprayer but comes with the connections to get onto a rad bleed hole.

 

[Agile]

Yes, I would add acid and then pressurise that to flow into the blockage under air pressure.

But its potentially messy and not ideal for doing in a carpeted room.

But then if enough time is given then using acid just into the blocked rads does often solve the problem.

These are not a lump of blockage which can me moved along but a buildup of sludge well adhering to the walls of the tube and often at a joint or change of direction.

Pressurising with air can indicate if there is any movement past the blockage. If it does then there is always a hope.

Tony