Powerflush or re-pipe?

[Ben-gee]

Inherited heating system (in when we bought) has been poorly maintained, no inhibitor most radiators rusty, several places when a magnet sticks to a copper pipe.
Also inordinate amount of creaking/popping as system heats/cools.

Combi boiler on ground floor, most rads on drops from reasonably accessible loft space (chalet bungalow), some drops feed two rads.
A recent extension by us has wet under floor (not connected up to system yet)

We need to replace the boiler as it will not cope with extra requirement.

Question is ; I am thinking of renewing copper pipe to all rads before a GSR replaces the boiler and connects up the underfloor. This would be instead of a powerflush; is this a mad thought?

 

[king of pipes]

If you do the remaining system dirt will end up in the new rads pipework and underfloor you need to replace as much as physically possible ,think I would say replace the lot in the spring/summer and still have it powerfulshed . Kop

 

[ShaunCorbs]

If your staying there for a long time I would replace

 

[Ric2013]

Even if you re-pipe 100% it is worth flushing (perhaps a powerflush would be OTT in this case) to get oils and fluxes out of the system. And let's not forget that new copper tube often contains copper swarf.

 

[WHPES]

Creaking and popping is pipe too tight against timber etc. A simple fix is to loosen pipe clips and enlarge holes that pipe passes through.

You could try an agressive system cleaner first. They are quite effective at removing deposits. Make sure you give long enough to circulate, and flush properly afterwards.

If you are not renewing rads, after you have drained off the system cleaner, take the rads off and thoroughly swill out with a hosepipe, sloshing water around plenty inside. Gets far more debris out than flushing alone. When system is thoroughly rinsed, be sure to fit a system filter to pick up any more debris. If your system is open vented (with tank in the roof space) convert to a sealed system.