[bendrick]

I'm a gas engineer, nowhere near you I'm afraid.

just pointing out that the old back boilers can quite often be attached to 30, 40 or even 50 year old pipework and rads, and new sealed system combi boilers will operate at about 3 or 4 times the water pressure of a traditional open vent tank fed system.

Which in many cases will result in blown joints, radiators and split pipes all over the old system (especially if there are any buried in concrete floors runs).

I don't wish to appear alarmist but it is a very real and regular occurance where just the boiler is changed over on an old system which is why many reputable C/Htg firms wont just change an old back boiler but will insist on quoting for a complete new system ( and often be accused of 'trying it on' for their pains if pointing out this very real occurrence )

So I would be very wary of using any firm which doesn't point this out when quoting should the rest of the system be as old as the back boiler which it normally would be.

Having supervised the installation teams of a firm changing over 50 old boilers to modern sealed system condensing combi boilers a week under the Nest scheme and facing this subsequent problem countless times every day I just thought that I would warn you of this in order that you can question anyone giving you quotes about the overall state of the rest of the system.

I'm afraid that replacing the whole system if recommended is rather expensive as I'm sure that you would already suspect.


BTW everyone carrying out paid for gas work has to be qualified and registered with Gas Safe whether in a private or rented property.