Can you have too much CH inhibitor?

[pistonheadforum]

No idea what the current system contains - might have already been some put in but I suspect not.

It's an open vented gravity fed with a F+E tank.

Safe to just dump a bottle of inhibitor in it or can too much cause problems? Soft water area if that makes any difference?

Screwfix cheapo recommended?

Thanks in advance.

[Mr Pointy]

Not unless you completely filled the system & even then you would just damage your wallet. Use something decent like Fernox or Sentinel.

[pistonheadforum]

Thanks - is it still needed for a soft water area?

[gfreeman]

pistonheadforum said:

Thanks - is it still needed for a soft water area?

Yes.

An inhibitor inhibits.

A CH inhibitor inhibits the formation of corrosion (rust) as well as other stuff (dependant on brand and type).

It also inhibits bi-metallic corrosion from the fact you have a mix of metals in your system.

Also rumoured to prevent Covid so that nice Mr Trump told me so I regularly take a swig from my trusty bottle of Sentinel.

Never did me any ha

[Mr Pointy]

pistonheadforum said:

Thanks - is it still needed for a soft water area?

Yes; it stops rust formation.

[MattyD803]

I was told by the Vaillant engineer that services our boiler that too much inhibitor (we use Fernox F1) can causes bubbling/frothing (?) within the heat exchanger and ultimately damage it....so probably the best not to over do it.

If in doubt, drain it down, refill and do a rough a calc on system volume (either kw and/or number of rads) and dose it properly....like a coolant change, it'll only offer a benefit to the system health to do a refill anyway.

[pistonheadforum]

Thanks all.