Combi Boiler - hot water help!

NOTHINGISFOREVER

Any plumbers in the house?


This seems to be diverter valve related, I'm guessing (based on previous problems several years back). Combi Boiler. Central Heating is fine, although initially when boiler is turned on, there is a sorta buzzing/vibrating sound. That stops once boiler gets going as rads begin to heat up. It's the hot water that's the problem. Well, lack of it, really. When hot taps are turned on, it takes for them to be fully on just to get lukewarm water, which then alternates between seconds worth of hot water, then generally tepid then cold etc. Driving me mad anyway.



Any ideas?



Thanks! :beer:

Alex1983

Blocked heat exchanger by the sounds of it, what boiler is it?

NOTHINGISFOREVER

Hi Alex.
Thanks for replying. It is a Sime Friendly boiler. If it is a blocked HE, is relatively easy to clean out/replace?

Thanks!

JimmyChanga

Not familiar with Sime boilers but if you're quite handy with DIY then it's not hard to remove the DHW heat exchangers usually. Typically 2 screws holding them on.

Check your boiler manual - usually have full instructions in replacing parts.

You can either try and clean out the original exchanger or just replace it. About £30 upwards for a new part. Check ebay etc.

NOTHINGISFOREVER

Thanks, Jimmy. :beer:

NOTHINGISFOREVER

Further to my earlier posting on this issue (I've been on a course through work, hence the delay), got an engineer in to have a look and diagnosed a perished diaphragm in the diverter vave which he replaced there and then. All good. Well..... things were for almost a fortnight but now I'm back to square one with last night's discovery of no hot water again (unless I turn the heating on and even then it alternates between hot, lukewarm and cold!!).


Any idea what it could be this time? Not a knackered diaphragm again so soon, unless it's got blocked somehow and diverter valve is stuck in some sort of CH mode.