Biasi 24SE misbehaving

[stoneboy]

Hi,

I have a Biasi 24SE gas boiler which started playing up about three weeks ago. The DHW would sometimes go cold. This might be for just a few seconds or several minutes. Sometimes switching the hot water taps off and back on again would cause the boiler to fire up again.

I had not noticed any problems with the DHW over the last week or so and hoped the problem had cleared up. Over the last 24 hours though the CH has been on constantly. It has an external thermostat and the CH keeps going even if I disconnect that (there was a wire between the thermostat contacts before it was fitted so the CH should not work at all with no connection there).

Given these problems, I think I need a new PCB but I'm in no way confident about this. I think my options are:

Replace the PCB and risk wasting £120

Get my local engineer to look at it for £45 + whatever it costs to fix.

Get British Gas to fix it for their set price of £156

Does anyone have any suggestions as to what my best course of action is? Is there any more diagnosis I can do on this myself?

Thanks very much,

Jon.

 

[stoneboy]

Seems like I can get a refurbished PCB for £50 + VAT & delivery...

http://www.cetltd.com/default.asp?part=658

That makes it a much smaller risk. If someone could confirm that it is likely to be a PCB fault before I order that would be much appreciated.

Thanks,

Jon.

 

[Agile]

The water in your system is dirty and the RH gland on the diverter valve is leaking and has leaked into the DHW flow switch. Gland and switch must be replaced after cleaning the pin.

Thats normally a CORGI job as the gas valve has to be removed to gain access.

In addition the diaphragm in the diverter valve has perished and needs replacement.

We dont charge our customers £120 for a brand new PCB ! Actually about £24 less!

Tony

 

[stoneboy]

Wow! You can tell all that from my crappy descriptions!?!

You are my hero.

Seriously though, I really appreciate this. Thank you very much.

Reading through your comments again, I think what you imply is happening is:

When the water went cold at the taps, it was getting water from the CH system (it was in fact most noticable first thing in the morning when the CH had not warmed up). The boiler wasn't firing as the water in it's internal DHW system was hot.

Then, when the heating was on constantly it was because the system thought it was heating DHW but this water was going into the CH system. Is that about right? (Not that it makes much difference to what I'll have to do about it, I'm just interested.)

As for getting it resolved, unless it's going to be much cheaper to get a local corgi engineer to fix this I think I'll get BG to fix it for £156. That way I'm covered if they find any other problems whilst fixing this one. Does this seem like a good idea?

Thanks again,

Jon.

 

[Agile]

I am not sure your assumptions are very accurate!

I think BG only fix ONE fault at that price!!! they will want to powerflush at another £500 before they will give any guarantee.

Best to get a competent local engineer and if you cannot find one then call Biasi on 0102 506 1340 for details of their local Service Agent.

Tony

 

[stoneboy]

Ah, I see. I'll try and find another engineer then. I spoke to the biasi guy yesterday and it will be a couple of weeks before he can call at a time when we are in.

Thanks again.

Jon.