New Gas Boiler - Flushing the system

[MikeFromLFE]

I'm going through the hateful task of getting quotes for replacement of my ageing combi-boiler.
I've had the first bloke come round and he has offered a couple of sensible suggestions beyond what I asked for. He is happy to install a Valliant (which appear to be the dog's doo-das) but he recommends an Intergas Rapid - which seem to get glowing reports from installers and users.
Leaving the choice of boiler aside - he is very reluctant to flush my system, in fact he is avoiding giving me a price to do it. He says that given that my system has been in place for 35 years, flushing might throw up leaks and weak points in the pipework. His solution is to do what he calls a 'Hot Flush' - as far as I can tell this means getting the radiators as hot as possible and then draining the system down, followed by putting in a user-servicable filter, for me to empty monthly.  To my uneducated small brain this 'hot flush' sounds like bollocks, and although the filter is a good thing, I can't see that it would meet the usual requirement to flush the heating system before putting a new boiler in.
Of course, not flushing the system would save me money, but would this be a short term saving at the expense of the boiler going south sooner rather than later, and a warranty claim being rejected?
All thoughts welcome.

[Canardly]

A lot of heating engineers are loath to power flush an old system for the reasons quoted. Indeed I have recently had my boiler relocated during building work and experienced a number of subsequent problems with rads staying cold but the engineer is persisting with removing air locks and gentler forms of chemical treatment. He has whacked the system up to max for a number of hours on two occasions and eliminated known problem areas by physically removing pipework in the cyclinder cupboard, examining potential air trap areas and replacing same. TRVs and the pump have been replaced.  The system is now clean.

He has advised me to replace the older rads in the house in due course (40 years old?).

The filter is pretty much a must these days and they are easy to isolate and clean.

[bryn]

I was very pleased with the quote and the job that - surprise! - British Gas did putting a new boiler in a year ago.  They have numerous special offers through the year so it is worth waiting for one of those to appear.  The best thing about the quote was that it was on the basis that it included anything they had to do, whether they had spotted it initially or not.  So all the unexpected extra work that was required with the pipework and valves  in the loft and airing cupboard was all done within the original price.  Other quotes from local tradesman warned of extra costs if anything else was required.

An extended power flush was included, and I had thermostatic valves added to all radiators at the same time (again for a much better price than the locals were quoting me).  The thermostatic valves converted the heating system from one which only warmed up the kitchen (despite years of tinkering with "balancing the system") to one that would warm up the whole house. Result!

Good luck.

Bryn

[robgul]

I was very pleased with the quote and the job that - surprise! - British Gas did putting a new boiler in a year ago.  They have numerous special offers through the year so it is worth waiting for one of those to appear.  The best thing about the quote was that it was on the basis that it included anything they had to do, whether they had spotted it initially or not.  So all the unexpected extra work that was required with the pipework and valves  in the loft and airing cupboard was all done within the original price.  Other quotes from local tradesman warned of extra costs if anything else was required.

An extended power flush was included, and I had thermostatic valves added to all radiators at the same time (again for a much better price than the locals were quoting me).  The thermostatic valves converted the heating system from one which only warmed up the kitchen (despite years of tinkering with "balancing the system") to one that would warm up the whole house. Result!

Good luck.

Bryn

I could have written that word-for-word after our BG boiler replacement in April 2016 - service and price couldn't be bettered - and we were flushed!  The only PITA was the cost of scaffolding In the deal) going up and down (3 storey house) to put a new flue through the roof.

We were told that the flushing was a necessary part of the work in order to warrant it.   We have small-bore copper pipes and aluminium radiators.

The icing on the cake was was getting the Hive system for "free" - well, bundled in the deal.

Rob

[jiberjaber]

I'm going through the hateful task of getting quotes for replacement of my ageing combi-boiler.
I've had the first bloke come round and he has offered a couple of sensible suggestions beyond what I asked for. He is happy to install a Valliant (which appear to be the dog's doo-das) but he recommends an Intergas Rapid - which seem to get glowing reports from installers and users.
Leaving the choice of boiler aside - he is very reluctant to flush my system, in fact he is avoiding giving me a price to do it. He says that given that my system has been in place for 35 years, flushing might throw up leaks and weak points in the pipework. His solution is to do what he calls a 'Hot Flush' - as far as I can tell this means getting the radiators as hot as possible and then draining the system down, followed by putting in a user-servicable filter, for me to empty monthly.  To my uneducated small brain this 'hot flush' sounds like bollocks, and although the filter is a good thing, I can't see that it would meet the usual requirement to flush the heating system before putting a new boiler in.
Of course, not flushing the system would save me money, but would this be a short term saving at the expense of the boiler going south sooner rather than later, and a warranty claim being rejected?
All thoughts welcome.

I'd assume the filter is on the return side of the CHW so would in effect protect the boiler better than simply relying on hope that a power flush had cleaned all the system through?  Over time the system would clean itself through the filter which you'd need to keep on top of obviously.

I had vague plans on sorting out our central heating this year, but it seems to be slipping to yet another thing that might not get round to!