New Boiler - Weather Compensator?

[FiF]

herewego said:

I thought hot water tanks were supposed to be at least monthly heated to 60 for legionella? Do boilers not automatically vary the output temperature depending on the house temp. so when the house is cold the output temperature is high to minimise heat up times then drop to 50 when up to temp?

I can't speak for weather compensated system, but our boiler varies output according to outlet and inlet temperatures on the circuit. It does this by modulating the burner, ie different fan speeds.

Temperatures are set manually, I run at 69°C out and generally inlet is about 58°C when it's running in steady state. Radiator delta T is aimed at about 50°C, usually a gnat's under that in operation.

Still not checked consumption Vs sq ft, been out in pissing rain all morning, just warming through.

Heating systems are complicated to us thickies. We had one of those pub rambling natters where one chap was moaning his system took forever to warm the radiators from clock cold start. Like over half an hour to get even vaguely warm. As notes were compared realised ours warms up quite quickly in comparison to others. Only explanation I had was it's microbore which is supposed to heat up quickly.

Anyway a few weeks later I had a few mornings up and about at around the time the heating comes on, so instead of just clicking the controller on as soon as got up monitored it to see what happened. Yep my inner nerd emerged.

Surprised to see that, when the time came, pump fired up for a while during the boiler start up checks, but only demand was on the hot water circuit, motorised valve operated, boiler fired up. Watching the inlet temperature readout it rose far faster than expected, which to me seemed as if it was dragging heat from the DHW cylinder. Boiler ran like that for a time, getting up to temperature nicely round that circuit, then demand on heating came on, motorised valve operated, nice hot water straight off to rads.

No idea if that's normal setup or not, but it certainly seems effective.

[herewego]

FiF said:

I can't speak for weather compensated system, but our boiler varies output according to outlet and inlet temperatures on the circuit. It does this by modulating the burner, ie different fan speeds.

Temperatures are set manually, I run at 69°C out and generally inlet is about 58°C when it's running in steady state. Radiator delta T is aimed at about 50°C, usually a gnat's under that in operation.

A quick scan tells that they don't condense if the return temp is above 55 so does the boiler tell you if it's condensing or not and do the instructions tell you how to make sure it is condensing?

[FiF]

herewego said:

A quick scan tells that they don't condense if the return temp is above 55 so does the boiler tell you if it's condensing or not and do the instructions tell you how to make sure it is condensing?

I'd have to have a look at the instructions, there doesn't appear to be any indication on the panel whether condensing or not, apart from the sound of the condensate trap regularly siphoning the condensate into a drain.