Inhibitor for radiators AND underfloor heating?

[hellopaul2]

Hello,

I have recently had an extension built with underfloor heating, which runs on the same circuit as my radiators. It all works perfectly and is nicely balanced, but it hasn't yet got any inhibitor in the system. I've seen various fungicide kinda things formulated for underfloor heating, but I'm guessing that if the water's at a temperature high enough, any bacteria will get killed as it runs through the boiler. Or is it the length of the pipe run that's the issue; ie. the water is cool enough at the far end of the run that bacteria could grow?

So, can I use bog-standard Fernox/Sentinel/No Nonsense inhibitor? Or do I need something fancy?

Thanks,

Paul

 

[Dan Robinson]

Normal stuff is fine.

 

[hellopaul2]

Thanks! I suspected as much.

Now - does anyone have any thoughts on which brand of inhibitor is "best"? Or do they all do pretty much the same thing?

Thanks,

Paul

 

[gigz]

Fernox/sentinel are similar quality. I've used the cheaper ones (when customer has supplied it) but i wouldn't put it in my own system. Not saying its no good but i like what i like.

 

[Dan Robinson]

Got 7 bottles of Altech inhibitor in my system.

Seems to work fine.

 

[gigz]

Seven bottles how many rads ? Litre bottles ?

 

[Dan Robinson]

300 litre thermal store, several hundred metres of UFH plus the rads.

Thought I might as well .

Actually - I just checked and there's only 5 stickers on the tank.

 

[hellopaul2]

Hmmm....I just ordered 2x 1 litre bottles of Sentinel X100. Hopefully that will be enough for my 8 rads + 35 square metres of underfloor heating (well, the floor area is about 35sq.m., but there are fairly large chunks with no UFH, eg. under kitchen cupboards).

- Paul[/i]

 

[St0rmer66]

Hmmm....I just ordered 2x 1 litre bottles of Sentinel X100. Hopefully that will be enough for my 8 rads + 35 square metres of underfloor heating (well, the floor area is about 35sq.m., but there are fairly large chunks with no UFH, eg. under kitchen cupboards).

- Paul[/i]

1 litre probably enough. If you put too much in it can cause "foaming" in the pump.

 

[therealdiy]

just learning about UFH, in the textbooks it states that radiators should be kept on an entirely separate circuit than the UFH - I'm very interested to hear this is not always the case - or I may have mis-interpreted your scenario!

Why are your UFH and radiators able to run on the same circuit? Any ideas?

If they are different circuits, the inhibitor needs to be added at the manifold as well as in the radiator

 

[hellopaul2]

My setup uses the same water in the rads and the UFH, but each has its own valve and pump, so I can run either the rads, the UFH, both, or just my hot water. So they share the same water/inhibitor, but can run independently. It's an open-vented system with a small header tank in the loft.

Having said all that, I haven't run the heating much so far - it was only installed in around July, so haven't had much need for it. I know it all works, but it will be interesting to see how well it performs this winter.

Hope that helps!