Power flush?

[75pete]

Open vented system. inc. hot water.
Hi, my problem started with a loss of heating when the boiler started then stopped and was kettling . So made a check of the F/ E make-up tank, level was correct, and ball Valve o/k.
When i bleed the first rad up stairs found no water. So first idea was to look for a blockage in the heating system.

Drained system at lowest point and also drained water at boiler - some muck as expected. Then also had to drained F/E as this did not drain. So yes its a blockage as in the past the system always drains with no problem.

With the F/E now empty by me tipping out the water i blocked off the vent over flow and connected the down side of the makeup water feed to the mains supply and gave the system a good flush.

Remade system and filled but not getting water to bleed and think that the blockage must still be there..Should a power flush be able to clear the flow / return circuits of sludge.
Will say at this point that a new boiler, hot water cylinder and pump was fitted in 2003 and think the pump has loosened some build-up /sludge

Anything more i should be thinking of or doing or missed?
Thanks.....Peter

 

[ChrisR]

It would clear some but not all. Hard deposits of rust/scale aren't dissolved by anything which wouldn't dissolve your copper or iron. A certain amount doesn't matter, but if pipes are solid with it they have to be removed.
It sounds like you've used no chemical at all though?

 

[gas_man_gaz]

personally i dnt think a powerflush wud push it through, ya prob best chopping out the cold feed and clearin the blockage with a screwdriver. id also put sum fernox inhibitor and some silencer in!

if ya struggling to find the blockage sometimes help to trace a magnet around the pipework

 

[JPC]

i did a power flush once where things were not going as they should..hooked up to the pump...fired the boiler everynow and then to do a warm/hot flush, but some rads where not warming up as expected.

turns out the feed pipe where connected to the flow pipe was blocked....as gaz said, got my magnet out and found it to be at this junction, which is where they normally get blocked up.

i cut it out ....well you could hardly see light through the pipe it was solid with scale/ build up

 

[75pete]

Thanks for your replies, no did not use any chemicals during my flushing. When the new boiler etc was installed back in 2003 it also had new Fernox inhibitor. The magnet, what size do i need ?

 

[GasMan1965]

A strong magnet

Blockage WILL be where cold feed joins the primary ..

 

[75pete]

Thanks GasMan, where can i get a magnet?

 

[andytheplumber]

Magnet and southern. Ha Ha

 

[GasMan1965]

Any old speakers sitting around ??

 

[75pete]

Thanks GasMan. He`s a card that Andy, Magnet & southern..........did give me a [ small ] chuckle on a gray day.

 

[75pete]

Well, after doing more checking i came across a bend, almost 90deg in the down feed. The feed also acts as a vent for the Recirc pump as its sits just behind it.
Cut and removed 90deg bend, was a bit of a bug.... so i see now why the "plumber" went for the easy way.......the git!
Anyway, system refilled and tested and appears o/k, so did not need to power flush.

Thanks again for your ideas etc..........Peter

 

[no66]

Hi
Can You explain how the magnet is to be used in tracing a blockage ??

 

[ChrisR]

Blockages are usually iron based oxides, like magnetite.

 

[no66]

Okay but the magnet would stick to the pipe any way so how do you trace the blockage ??

 

[JPC]

only to lcs pipes...not to copper and plastic !!