Worcester 28i RSF - water keeps going ice cold...

[northcoombes]

Hi there
We have a Worcester 281 RSF boiler, in a three bed semi in a hard water area.

Lately we have found that the hot water will suddenly go cold. We have noticed this in the shower, bath and kitchen. The water will be nice and hot, suddenly drop to ice cold and then eventually go back to hot. The cold water intervals are becoming more frequent and lasting for longer. This morning I ran a bath and when I went to test the temperature it was ice cold! I then tried the shower and basin - both cold. Went downstairs ran the kitchen hot water and then it came right. I was able to have a shower but it still went cold at intervals. I had a look - the boiler pressure is at 1. We did have it flushed about a year ago because the hot water pressure had become increasingly low.

We will call in a Corgi registered plumber but any ideas what we are dealing with and possible costs? - we are from Australia so boilers are totally foreign to us

Thanks for your help.
Michelle

 

[gas4you]

Sounds like it is overheating, possibly due to scale build up in the dhw circuit.

Are you in a hard water area?

 

[northcoombes]

Hi Dave

Yes we are in Berkshire and we have a lot of trouble with hard water. If it is that would it be a big job to fix?

Thanks
Michelle

 

[gas4you]

It could be that a local engineer may try to use a strong descaler on this side of the boiler, or they may say you need a new heat exchanger. Either way, to me who is not a worcester expert, I would say it is quite a time consuming job.

It may even be a simpler fault than this once it is inspected.

The flush you had last year would not have cleaned the dhw side of the boiler.

Other WB experts who post on here will be able to advise in more detail.

 

[northcoombes]

Thanks Dave. I appreciate your input.
Kind Regards
Michelle

 

[niksho]

Hi, I saw your post from a while ago about your boiler problems. I have the same problem, but I live in a soft water area. What turned out to be wrong with your boiler?

Thanks, Nik

 

[bellairaphon]

does the boiler shut off fire up??? get someone to stand next to it. also try putting abit more pressure in the system 1.5 when cold. and are u having to reset the boiler??? thinking air pressure switch myself if not the pressure but scaling is a good possibility