Balancing radiators - differential across radiator ?

[Huge]

*LAUGH* That's *exactly* how my wife treats thermostats.

[nothanks]

I looked at Genius but can't now remember why I went with Evohome - from a quick look at Genius they seem to have similar features. The evohome rad valves have integral thermostats, but wall stats are available.

[nothanks]

:-)

[Tim Watts]

Same: Genius was previously not able to make use of the rad valve temp sensing - but can now (with the usual pros and cons of it being next to the heat source and/or window drafts).

One thing Evohome seems to have that Genius doesn't is a stand alone command centre panel - that's cute. Genius really need something like that that you can nail to a wall - but they seem to have gone down the app/web route.

[AnthonyL]

I had a go at the Genius "Define my system" page and it has a drop down for TRV valves. I have some that are labelled E29 with what looks like a o above the E but I can't find them in google. Any ideas?

[Tim Watts]

The Genius rad valves are Danfoss LivingConnects (LC2 IIRC)

[Tim Watts]

Quick follow up -

Got the rads really well balanced between dT=8-12C (except the tiny bypass rad which has only a few degrees across it.

One thing I found was that it seems like a good idea to jack the boiler up to 65-70C and balance conventionally at dT=12C

Reason - even with windows open, at a low flow temp, the rooms get so hot in the time it takes, that the boiler ends up cycling a lot which buggers up temperature measurements - and the radiators struggle to lose heat to the room.

So the motto is: balance hot, then turn the boiler down to what works.

2nd motto: a differential temperature meter with 2 pipe clamp thermocouples really speeds this up. My IR meter was very random and unrepeatable with the pipe - possibly a mixture of the pipe area and the emissivity of copper that varies *massively* with how polished/oxidised the surface is.

[John Rumm]

Masking tape targets on each pipe tail, sorts that - the IR thermometer can then get a sensible reading.

[Tim Watts]

I did try black insulation tape - but it still seemed a bit random. Maybe my IR meter is a bit crap?

[Andy Burns]

What's the size of the "sampling circle" for your thermometer at whatever distance you were measuring from?

[John Rumm]

Did you get in close enough with it? The laser dot can lead you into a false sense of how small the reference patch is - its actually quite large.

(alternatively a reading off the painted corner of the ran dearest the inlet/outlet is normally good enough)

[Tim Watts]

On paper, sufficient for the target at the distance - but in practice, the readings were all over the place.

[Vir Campestris]

:) know what you mean.

When we had our boiler replaced they put in new controls. They put the thermostat over where the old one was, which meant in a stick-and-s**t house like ours there was a cold draft up its backside. WTH, I though, it's wireless. I'll move it.

Onto a bit of wall that turned out to have a rad pipe behind it, and could be 5 degrees hotter than the rest of the wall...

Seems to be OK in the 3rd position. Still training SWMBO.

Andy