Micro bore heating system blockage?

[DavidC]

I'm hoping that a some of you may have a few ideas to help me.

There is a blockage in a micro bore heating system, hot water leaves the boiler then the boiler cuts out on the thermostat with all the radiators still cold. When the boiler is then switched off, the hot water flows back up the supply pipe through the pump, with the supply pipe finishing red hot and the flow pipe cold. Could this be the result of a blocked supply pipe causing a vacuum or a faulty pump? There are 2 automatic release valves fitted within the system. Any thoughts on the problem would be gratefully received.

 

[PlumbBobBob]

has this been going on for a length of time or only just happened?

 

[DavidC]

No. The system was drained down to fit thermostat valves on radiators.

 

[Gray0689]

No. The system was drained down to fit thermostat valves on radiators.

Get in a plumber

 

[PlumbBobBob]

i agree get a plumber in, could be one of several things

 

[DavidC]

We did and that is what caused it! Just wondering if anyone else had possible thoughts

 

[Gray0689]

We did and that is what caused it! Just wondering if anyone else had possible thoughts

Get the plumber back then to sort it

 

[PlumbBobBob]

where are you? someone on here may be near you and can come out. post a request [DLMURL="http://www.ukplumbersforums.co.uk/im-looking-plumber-gas-engineer/"]here[/DLMURL]

 

[DavidC]

Get the plumber back then to sort it

We did... He is struggling for ideas as well, that is the only reason I have asked for ideas off the rest of you. Thank you for your help though.

 

[Gray0689]

We did... He is struggling for ideas as well, that is the only reason I have asked for ideas off the rest of you. Thank you for your help though.

If he thinks it's a blockage it will probably need flushed

 

[Chalked]

When you say microbore, is it copper or 10 mm hep2o ( plastic) and what is the age of the house/ system?
it makes a difference.

 

[Ermintrude]

Surely it's 22mm to manifold and air cupboard. Bet its and air lock on pump. Take a picture of airing cupboard set up. Is it a combi or do you as I assume have a hot water tank??

Is pump running? Bet it's red hot but pipes are cold?

Stupid question but are rads full? Is small tank in loft full? No valves turned off?