Feed Pipe Blocked in Open Vented Central Heating System

[self builder 123]

Hi

The feed pipe from our header tank to our CH system is blocked.

I think that it is iron oxide which came from inside the radiators as I found a mix of sludge and particles in the bottom of the header tank ?

The system was drained sometime ago and I know that is was not recharged with inhibitor so I am not surprised.

My question - should I try to clear the blockage risking pushing the dirt into the system and possibly blocking the pump or would it be best to simply cut out the blocked section of 15mm pipe and replace ?

 

[moggridgeplumbing]

Easiest way is to cut it out and replace. The reason you make black sludge in your F&E is because water has shot up the expansion.

Whole system probably needs a good flush after you replaced the blocked cold feed.

 

[self builder 123]

Cheers

Once I replace the section of pipe I plan to add Fernox Restorer ( as it is an old system ) and circulate this around to gently remove any loose particles of oxide and then drain and flush the system a few times before refilling and adding Fernox Protector.

 

[grahamtheplumber]

red sludge=oxygen present when formed ie pumping over.
black sludge formed in water with no oxygen .
fit a magnetic filter on the system like a Adey
Magnaclean or equivalent,i fit one to every new boiler change.

 

[moggridgeplumbing]

red sludge=oxygen present when formed ie pumping over.
black sludge formed in water with no oxygen .
fit a magnetic filter on the system like a Adey
Magnaclean or equivalent,i fit one to every new boiler change.

Quite correct Graham ,although black sludge would not be present in the F&E unless pumping over had happened.

Magnetic filter highly recommended - always fit when replacing boilers though not Magnaclean.