Solid Worcester 24i Junior - limescale

[ChrisR]

I'm fishing for limescale experiences.

This Heat exchanger is solid with limescale at 2 years old. Only a dribble of tap water getting through it. It's the combined primary/secondary type.

I suppose I could try to descale it, though I'd prefer to renew it and have a go at cleaning the old one at my leisure. (also the filling loop was open, mains 2.2 bar, and the boiler was dripping generally, so....)

This is Epsom, apparently very hard water. There was an old, roundish out-of-use Quantomat connected to the pipe which might have helped "if", I suppose - any comments on those?

I haven't had a lot to do with very hard water but imagine a plate-type heat exchanger might have fared better , and been a bit easier to clean.

 

[Paul Barker]

You have to wander whether the biflow heat ex is tough enough to withstand the rigours of the powerful descaling you have to embark on. I think I'd bin it. I think they had a bit of trouble with those things leaking at first in areas where maions pressure has been known to rise to 10 bar at night. That would imply they are weak structured. Would you want to be responsible for it? I wouldn't, sure it would lead to a MIF (maintenance induced failure).

 

[Nige F]

You`d be MIFFed if it let u down

 

[ChrisR]

Apparently Worcester replaced the heat exchanger under warranty at only 6 months old because it was blocked with scale (nice of them!), after which a COmbi-Mate was used. (Or similar polyphospate bead softener)

Evidently that went out of use at some time - rented flat - nobody realising you have to put "stuff" in. SO after another 18 months it's blocked again.

Unhappy situation for all. Also a combination of a fairly unpleasant/mean landlord, stroppy tenants, and filthy flat, so I'll be busy elsewhere...

 

[Paul Barker]

Ah, lovely scenario. I have one of those, mean winging landlord, tenant doesn't even want to be taught how to use filling loop.

Great pair to be sandwiched between!

 

[Agile]

I have not worked out what it is yet but there is some kind of design fault with that boiler which causes the DHW tube to get limescaled which should never happen.

Thats the only type which I ever encounter which get scaled up in the London area and there is not obvious reason why it should.

Epsom like Bracknel is very hard water.

I have successfully descaled one of then using a power flushing pump. Like yours the flow through the tap had reached almost zero.

Tony

 

[ChrisR]

A small detail - somebody - presumably Worcester, had removed the flow filter and regulator, possibly to reduce the temperature of the tap water and the opportunity for the temporary hardness to precipitate. The mains pressure certainly wasn't bad, so not a case of mains starvation. On reflection it was a house, with its own supply, not a flat.

 

[Agile]

I think that you are giving too much credance for thought there!

I am sure the flow regulator was removed in a vain attempt to increase the flow rate as it was scaling up!

Tony