Baxi Combi 80 Eco DHW Problem

[stef99]

Hi, Im new here, so I will try and keep this brief...

I have flushed my DWH heat exchanger twice, both times with a pressure washer and all sort of weird chemicals, However, my hot water only stays hot for about a week or so, and then it get clogged again.

So my question is...

If i flush the whole system with ferox, will the flush the hot water side, and if not, how do I go about a full flush for the hot water?

Thanks Stef.

 

[Agile]

Using weird chemicals is unlikely to achieve anything.

It sounds as if you have a very dirty system.

The easyiest solution is to fit a magnetic filter to catch the dirt.

But your boiler should have a filter in the return isolation valve. Do you clean that regularly or is it missing?

I dont know what "Ferox" is! Sounds like a mutant fox.

Tony

 

[riveralt]

You should have your whole system power flushed before fitting a magnetic filter. A lot of your grime (iron filings) will be lodged at the bottom of each radiator and this will make its way to the boiler - the magnetic filter takes out part of this sludge - but its always better to start with clean system. The alternate is for you remove each radiator and thoroughly clean it with a high pressure hose - not recommended today - tooooo cold.

We use Fernox by the way.

 

[stef99]

Thanks for your reply,

Im quite surprised that the boiler uses the central heating pipes to heat the domestic hot water, but maybe thats what the second heat exchanger is for.

So just to claify, when you turn on the hot tap, it automatically starts to heat the radiators, but then diverts the water to the tap, and uses the water from the closed circuit (central heating) to heat the DHW.

Thats how the water goes cold, cos the dirty water from the radiators is actually used to heat the water also?

Also, can I just check, do you know what version of ferox to buy?