Should my CH inhibitor be topped up occasionally?

[alan333]

Hi,
Should my central heating inhibitor be topped up periodically?
It's a gravity fed system with a header tank in the loft. Inhibitor was added by Scottish Gas when they did a powerflush a couple/few years ago. Can't remember which brand but could check an empty bottle in the loft if it would help.

I occasionally check the header tank and have emptied, cleaned and re-filled (the header tank only, and filled with only water) twice since the powerflush. The first occasion it had a sort-of crusty white/grey layer on top, the second occasion it had some 'wispy muddy clouds' floating around in it.

The system is a 17 years old Baxi boiler feeding 12 rads plus dhw cylinder. It works perfectly, has a magnetic filter fitted, and is serviced annually. I recently drew a little water from the downstairs rad drain valves and all were almost clear.

Thanks

 

[flameport]

Should my central heating inhibitor be topped up periodically?

No. It can only be lost through leaks or draining the system.

 

[JohnD]

it had a sort-of crusty white/grey layer on top, the second occasion it had some 'wispy muddy clouds' floating around in it.

you might have a fungal growth or bacterial slime in it. This does sometimes happen in loft F&E tanks, which can get warm in summer and may contain organic material from dust and drowned wildlife, or plumbers peeing in it.

If the water feels stringy or slimy or like jelly, bale it out, clean it thoroughly, wipe it round with bleach, including the underside of the lid and the ballcock and allow it to refill with fresh water. You can get a biocide called AF10 made by Fernox, you may have to order it, it does not seem to be widely stocked. Ask around as the price varies dramatically. There may be other brands.

The tank should have a tight-fitting plastic lid to keep it clean, and an insulating jacket to prevent it getting warm in hot weather.

 

[alan333]

Thanks for the replies guys. I'll remove it from the worry list.
The tank has a tight lid and a jacket. I'll continue to check/clean it periodically, and will look for AF10.
Thanks again

 

[AGAS]

fresh water. You can get a biocide called AF10 made by Fernox, you may have to order it, it does not seem to be widely stocked.

Why bother with that , your going to tell me you've got OCD in a minute

 

[Scarum]

Why bother with that , your going to tell me you've got OCD in a minute

I can't talk for JohnD but yes, there's no way I want slime and jelly in my tank. Fernox AF10 has stopped it in its tracks and the tank is as clear as a swimming pool

AF10 smells like Jeyes disinfectant- I wonder if that would make a suitable slightly cheaper alternative?

 

[durhamplumber]

Fernox AF10 has stopped it in its tracks and the tank is as clear as a swimming pool

you need to get out more!