Radiators not coming on - Powerflush necessary or a rip-off?

Doc_N

Relative's central heating radiators stopped working a few days ago for no apparent reason.

Covered by a home emergency policy, so they called out a subcontracting firm who say they can't find the problem (pump replaced, motorised valve seems OK) so they suspect an airlock or a blockage and plan to do a power wash to get rid of it.

Seems like a con to me (and potentially risky on an old system) - or am I being over suspicious?

I_have_spoken

Have they tried bleeding the rads?

Geoff1963

If the system suddenly stopped working ; that sounds different to the gradual clogging that a power wash would fix. Airlocks in the system should be easy to fix ; because when the system is first installed, it is one big airlock.

Do all the radiators bleed water when you open the screws ?

Does it have a header tank, and could something have got into the system that way ?

Doc_N

I_have_spoken wrote: »

Have they tried bleeding the rads?

Geoff1963 wrote: »

If the system suddenly stopped working ; that sounds different to the gradual clogging that a power wash would fix. Airlocks in the system should be easy to fix ; because when the system is first installed, it is one big airlock.

Do all the radiators bleed water when you open the screws ?

Does it have a header tank, and could something have got into the system that way ?

I'm no engineer, but what they've done so far is attach hosepipe to a couple of drain down points on the radiators, but that hasn't cleared what they claim to be an airlock. Radiators haven't been bled, but you can hear there's air in the system.

There is a header tank, which they've checked and say is OK.

This sounds like a failure of a motorised valve to me (and that's what they originally said it was) or some other sudden failure - not something a power wash will deal with, but as I said, I'm no engineer!

Alex1983

Does the hot water work?

Lorian

I haven't needed the heating on for months.

Tell us more about the symptoms.
What make/model of boiler
does the boiler light
Is the water heating
is the thermostat calling for heat
Do any radiators get warm
Are their TRVs on the radiators
lots of other things might have a bearing

Doc_N

Alex1983 wrote: »

Does the hot water work?

Lorian wrote: »

I haven't needed the heating on for months.

Tell us more about the symptoms.
What make/model of boiler
does the boiler light
Is the water heating
is the thermostat calling for heat
Do any radiators get warm
Are their TRVs on the radiators
lots of other things might have a bearing

Boiler works fine. Hot water fine. Thermostat on max. A week ago all radiators were hot. Now they're all stone cold. No heat whatever getting through to them but the hot water cylinder still heats fine from the gas boiler.

No controls have been altered in any way and the sudden disappearance of any heat at all to the radiators looks to me like a failure of a component in the heating system (not the boiler ) and nothing that a power wash can sort out.

Too cynical perhaps?

Alex1983

I'd be amazed if it's not a zone valve/ 3 port or timer/stat. If it that blocked to stop all the rads working I wouldn't think the water would work and the boiler would be noisy or over heating.

Can they get a 2nd opinion?

Doc_N

Alex1983 wrote: »

I'd be amazed if it's not a zone valve/ 3 port or timer/stat. If it that blocked to stop all the rads working I wouldn't think the water would work and the boiler would be noisy or over heating.

Can they get a 2nd opinion?

Pretty much my feelings. I'll be getting someone else in - I think these guys are pulling a fast one.

Alex1983

The only way I could see it, would be blocked manifolds on micro bore and the heat is going down the bypass pipework.

Doc_N

Alex1983 wrote: »

The only way I could see it, would be blocked manifolds on micro bore and the heat is going down the bypass pipework.

Interesting theory - would a power wash resolve that?