Central Heating Inhibitor

[ABN]

Had central heating installed some years back. Its a sealed system using a Worcester 28CDi combi boiler.

I often browse this forum hoping to learn and pick up new tips/tricks and recently noticed a few threads where it been recommended to add an Inhibitor when filling a central heating system.
Since its istallation I have had to drain the system a few times for other projects but never knew to add an inhibitor. I checked the boiler manual an could see no mention of it there.

With a sealed system based on a Worcester 28CDi boiler do you need to add an inhibitor an if so how ?

One other thing although its a combo boiler when the central heating is drained the hot water no longer heats up. Is this normal?
Thought the 2 circuits would be seperate and as such one should not efect the other.

 

[Agile]

Most parts of the boiler are common to CH and DHW and the system must be pressurised to work at all.

Some cowboys will say you dont need to add inhibitor. All manufacturers and the chemical makers will say add it. I also say add it but at the end of the day its up to you.

I will say that some systems seem to work very well for a long time without it and others even with it can get problems. Sealed systems are less of a problem if there are no leaks and everything operates well.

Tony

 

[ABN]

So sounds as if its worth adding ... but how would I go about doing that please

 

[Agile]

That depends on your system.

If you have a towel rail isolate both valves and open plug in top and suck out 1.5 li of water and add X100.

If no towel rail then use a rad and after closing valves open union to drain 1.5 li. Fill at bleed screw with a syringe or similar bodge to get X100 into it.

Tony

 

[ABN]

Fitting a new rad in the bathroom any day soon now so will put it in there then.

Thanks for your help/advice