Hi,

You may remember that I rent my old house out and that last summer the
boiler broke and the tenant was without hot water. It is a glowworm
combi boiler and the fan needed replacing. When the plumber replaced
the fan, something else broke, I can't remember what now - I must find
the paperwork, and so the plumber fixed that too.

This week I had a phone call from the tenant saying that the boiler
was leaking. The plumber who repaired it last time said that it was an
old boiler and he would not be interested in looking at it again but
he would fit a new boiler for me. Now I am prepared to admit that it
is an old boiler and might be time to replace it but I would rather
that he made that decision after diagnosing the fault rather than
before. Silly example but I don't want to replace the boiler just
because a compression joint has come loose for example.

I also thought that because I only had the repairs done 6 months ago,
the parts and work might be under some guarantee (12 months?).

I think I paid about £600 to fix it, so I was reluctant to rip it off
the wall so soon after spending all that money.

I don't live in the area any more so I don't know who the good and bad
plumbers are. I know British gas sometimes has a bad reputation and is
seen as expensive but I needed someone to look at the boiler ASAP and
I figured it would be quicker to call a 24/7 call centre rather than
wait for local one-man bands to return calls, and easier to track a
large company down if the work wasn't good or doesn't last long!

They tried to sell me insurance: £99 for the call out and repair the
fault, or so I thought. They have been but claim there are three
faults and their policy will pay for the first fault only. I need to
look into this. I can't remember what the first fault is, but no doubt
it is the cheapest!

They say that the leak is from the heat exchanger and the fan is
broken. I am disappointed that the fan has not lasted 6 months but he
said it definitely is a new fan, because I was paranoid the last
plumber had fiddled me!

Why do heat exchangers fail? Do they just rust through? Although the
CH has inhibitor, with it being a combi, does the DHW cause the
rusting?

Are there still problems with using the wrong type of inhibitor? Could
the plumber last year have put the wrong type in and caused the leak?

BG wanted £500 to fix these but when they learned the fan was recent,
they said they might be able to do a warranty repair. they have not
told me how much this will drop the price by.

So I could end up spending £1000 in 6 months on repairs. OTOH isn't
that what a new boiler would cost? Is it time for a new one? Am I
throwing good money after bad having this repaired?

BG's web site lists six boilers: BG own brand (rebadged presumably,
but what?), Baxi, Worcester, Valliant, Potterton, Glowworm.

I know a sample of one is not good but I am not keen on glowworm
having had the problems with this one!

I know Worcester are good but I guess that comes with a price.

I think Valliant are supposed to be good but don't know why; perhaps
it's something I have read here? Would they be the best of the six to
go for? What would you choose and why?

The existing boiler is a combi but I wonder whether to install a
non-combi? At least if that broken in the future, there would be a HW
cylinder to provide HW whilst the boiler was fixed. But that would
come at an increased cost. I live too far away to go and fit the
cylinder etc. myself and I doubt any plumber will want to do half the
job; presumably they would want to do the whole install?

What do you think?

TIA