Advice needed - can't get system working!!

[mattgrange]

Called to a customer's house today they were reporting no heating and lukewarm hot water.

It's a Y plan, fully pumped system

The boiler's working fine. The flow pipe is getting red hot up to the diverter valve and when calling for heat & hot water or hot water only the flow pipe into the cylinder coil gets very hot. The return from the cylinder coil never even gets warm. The pipe coming from the heating side of the diverter valve gots slightly warm in heating & hot water mode, but in heating only gets very hot. The radiators begin to warm up but VERY slowly. The return above the boiler never gets above cold!

The system has had a new diverter valve in the last few months and a new pump about a year ago (not fitted by me?)

Any thoughts please???

 

[payney1974]

sounds like a blockage where the cold feed meets pipework. Cut vent and feed out and fit airjec is a solution or just renew tee where blockage is.

 

[moogwai]

sounds like a blockage where the cold feed meets pipework. Cut vent and feed out and fit airjec is a solution or just renew tee where blockage is.

agreed

 

[Blackcatgas]

Called to a customer's house today they were reporting no heating and lukewarm hot water.

It's a Y plan, fully pumped system

The boiler's working fine. The flow pipe is getting red hot up to the diverter valve and when calling for heat & hot water or hot water only the flow pipe into the cylinder coil gets very hot. The return from the cylinder coil never even gets warm. The pipe coming from the heating side of the diverter valve gots slightly warm in heating & hot water mode, but in heating only gets very hot. The radiators begin to warm up but VERY slowly. The return above the boiler never gets above cold!

The system has had a new diverter valve in the last few months and a new pump about a year ago (not fitted by me?)


Any thoughts please???

Pump ,"fitted last year" was probably 2003, is there one of those myson sludge catchers sorry I meant Air jecks fitted? theses can fill up with crap and block the flow from the boiler.
edit Ive just posted this while other people have posted about air jecks, this wasnt a go at anyone about fitting airjecks lol, theyve just come up with the same answer as me about a blocked vent/feed tee.

 

[mattgrange]

sounds like a blockage where the cold feed meets pipework. Cut vent and feed out and fit airjec is a solution or just renew tee where blockage is.

The system was drained and it refilled fine so can't be a blockage on the cold feed from the tank.

Can't see an air jec on it, although it could be under the boards. Have worked on a few on this estate and all appear the same setup and don't have them.

 

[moogwai]

The system was drained and it refilled fine so can't be a blockage on the cold feed from the tank.

Can't see an air jec on it, although it could be under the boards. Have worked on a few on this estate and all appear the same setup and don't have them.

i had one the same a few weeks back......system filled fine but no circulation. i still cut out the neutral point which was 95% blocked so there was still enough room for the water from the f&e to fill the system.

 

[archiedale]

Must be blocked 😕, start again.