Rads don't need balancing...

[visionset]

I've got 22 between boiler and upstairs and downstairs and upper and lower circuits T'd off in 15. With such a system and my new combi it seems there is little need to balance. I've turned the pump speed down to it's minimum and most the rads are open full bore. I've just tweaked a little for one double rad that was a little reluctant. I will check the temp drops soon but they are all good and hot. In fact something not mentioned elsewhere that I've seen is that restriction unless really needed with a system that has no problem getting the water round just seems to result in a bloody whistling racket. I've not put the TVR's back on yet. No doubt I'll get a bloddy whistling racket back then anyway :-(

[VisionSet]

Comments? I was a little suprised.

[Mathew Newton]

I'd be interested to hear some too - my system (12 radiators (11 TRV'd) on a combi-powered sealed system) is currently unbalanced. Or, perhaps more accurately, all the lockshields are fully open.

Every radiator works well and heats up at the same rate... so would I still benefit from 'proper' balancing? Perhaps my feed/turn temperature differential is potentially 'sub-optimal'?

Mathew

[Ed Sirett]

The purpose of TRVs is mainly to prevent certain areas becoming over-heated. They have the fringe benefit that, eventually, provided the system is adequately powered, the system will be balanced even if it wasn't beforehand.

Ideally the system should be balanced initially with the valves off (or set to max).

Many combi models simply have a standard 3-speed pump motor set to max. The better models and more recent models tend to have the pump speed adjusted by the boiler's controls. This means that as the required output power falls the pump power can be reduced. The effect is to greatly reduce whistling. Different models seem to be more or less prone to whistling and amazingly the market leader is, IME, one of the worst.

Setting a lower pump speed on many combis will simply reduce the HW production rate.

Removing all the TRVs is against the spirit of the building regs if not the letter.

HTH

[visionset]

Yes that was the intention hence the reason the TRV's are removed at present.

Mine is the probably the one of your 'IME' a Vaillant (ecotecplus 837) since I know you tend to fit these. I'd not read that anywhere in the archives.

I've set the speed through option d19 to speed 1 for the heating. So you think I should put it back to the default speed 2?

Like I said it's only while I'm assessing the current situation.

So what I've said rings true then?

Thanks Ed!

[Ed Sirett]

Sorry I think the Pump on the latest Vaillant is varied. I meant to say different models of TRV and the Market leader is Dr*yt*n isn't it.

[John Rumm]

I found a Pegler ones that Screwfix sell whistle if on the return side - even though in theory they work both ways.

[Dave Plowman (News)]

My limited experience says only to buy the decent and therefore expensive ones. Shed types fail after about 5 years.

[visionset]

I thought the Peggler ones were decent. This was what I was considering as a replacement for my cheapo ones.

-- Mike W

[Dave Plowman (News)]

Could be. It's just that most things sold by Screwfix tend to be bargain basement type stuff.

[John Rumm]

I think they are decent in the sense that they work well, and according to some who have had them for a long time, seem to last. Just make sure you get them on the flow side.

(other than the whistle, they worked ok on the return side)