Some reassurance please. I have replaced my fifteen 40 year old
radiators, am still in the long and tedious process of balancing them
as described in the uk.d-i-y FAQs, and will soon be in the process of
upgrading the control side of things (using Honeywell S Plan). I've
bought a couple of 2 port motorised valves to put on the HW and CH
outlets on my standard oil boiler, but looking at them see that in
spite of being 28 mm fittings, the flow aperture of the valve looks
more like 15 mm. Are all these motorised valves designed the same
way, and are they likely to impede the flow significantly given that I
have so many radiators to heat?

TIA

Keith

Keefiedee wrote:
Some reassurance please. I have replaced my fifteen 40 year old
radiators, am still in the long and tedious process of balancing them
as described in the uk.d-i-y FAQs, and will soon be in the process of
upgrading the control side of things (using Honeywell S Plan). I've
bought a couple of 2 port motorised valves to put on the HW and CH
outlets on my standard oil boiler, but looking at them see that in
spite of being 28 mm fittings, the flow aperture of the valve looks
more like 15 mm. Are all these motorised valves designed the same
way, and are they likely to impede the flow significantly given that I
have so many radiators to heat?

TIA

Keith


Flow rate is not restrained by a small section of small bore half as
much as by a large section of medium bore.

And central heating doesn't actually NEED a massive flow rate either. A
little bit of very hot water is just as good as a lot of warm water..