no flow through boiler

two storey house with vented system and baxi boiler. Have had the BAXI engineers to fix a slight leak on boiler but when they tried to fill the boiler there was no flow . They think that the cold water feed is perhaps blocked with sludge although this enters the 22mm return flow just after the 22mm pipe vent rises to the loft . The 13mm cold feed is vertical from the feed tank and only horizontal for 40mm when it enters the return flow pipe at first floor level. The 22mm vent pipe then continues up to the tank with an open vent. I fail to see how the sludge could block the 13 mm feed pipe when it is only horizontal for 40mm as surely the 22 mm return would pull any sludge into it. The boiler apart from the slight leak was working fine before the fix and all rads. hot . The simplest solution would be to connect the cold feed directly to the 22 mm vent pipe in the loft and do away with the old 15mm feed pipe - would that work?

Not uncommon for the feed pipe to be blocked. Easiest solution is just repipe the cold feed?

EvilDrPorkChop said:

Not uncommon for the feed pipe to be blocked. Easiest solution is just repipe the cold feed?

Click to expand...

thanks EDPC - to replace the existing is a bit tricky as it does gp through a wall into the loft and not space to tackle it really whereas if i connected the cold feed to the 22mm vent pipe in the loft that would be easy or should the cold feed always be separate. The cold feed is connected to the 22mm return flow anyway just after the air vent rises to the loft so it would feed the 22mm return flow in almost the exact position as the existing

EvilDrPorkChop said:

Not uncommon for the feed pipe to be blocked. Easiest solution is just repipe the cold feed?

Click to expand...

thanks EDPC - to replace the existing is a bit tricky as it does gp through a wall into the loft and not space to tackle it really whereas if i connected the cold feed to the 22mm vent pipe in the loft that would be easy or should the cold feed always be separate. The cold feed is connected to the 22mm return flow anyway just after the air vent rises to the loft so it would feed the 22mm return flow in almost the exact position as the existing

If the system has been emptied then there could be air in the system

C Jackson said:

thanks EDPC - to replace the existing is a bit tricky as it does gp through a wall into the loft and not space to tackle it really whereas if i connected the cold feed to the 22mm vent pipe in the loft that would be easy or should the cold feed always be separate. The cold feed is connected to the 22mm return flow anyway just after the air vent rises to the loft so it would feed the 22mm return flow in almost the exact position as the existing

Click to expand...

Like my system except a longer feed pipe??