What is the purpose of Auto/Man Danfoss valve in airing cupboard?

Sounds like a 3 way valve with manual override. If the valve fails to actuate automatically you can move it to manual to get central heat. Normally it should stay on auto.

NT

snipped-for-privacy@gmail.com formulated the question :

The manual position is intended to help in purging the air out of the system.

Yeah, I'm not sure you can get the valve into the fully CH (typically) position with the manual lever, it needs the motor to take it there but that may depend on the make / model of the valve.

I'm pretty sure you can't with the ones I've been playing with anyway, the Honeywell V4073A.

Cheers, T i m

The OP does not actually state wether it is a two or three port valve just that he has moved the lever over to midway, I would suggest most two port valves at that point would allow flow through them. The peculiar aspect of his question is he claims his upstairs radiators are hot while the downstairs are cold which at first suggests two separate circuits but the common practice in these situations is to use two separate valves rather than a divertor valve.

We had a situation once where when heating DH water some radiators were getting warm (not hot) the cause was the return pipe from the DH joining the return from the radiators in question resulting in a back flow into the radiators in question. The remedy was to join the DH return beyond all the radiators plus a couple of non-return valves for good measure.

Richard

Unless a zoning valve, it sounds like your system needs balancing. This is where you equalise the flow through rads.

Manual normally moves it to mid position so CH is on as well as HW - the latter is on by default. Moving further would cut the HW off.

NT

First, note that this (cold rads downstairs) has only been noticed recently. The house was built in 2004, so that's how old all the heating installation is (apart from a thermocouple occasionally).

I don't know whether it's a two or three port valve. There is only ONE of these.

The cold rads downstairs only seems apparent when the lever is moved all the way to "Auto". At the moment I've moved it all the way to "Man" and the rads both down- and upstairs come on.

That's all I know.

But what does "Auto" in fact signify? Auto what, exactly?

MM

Now that I've moved the lever all the way to the right, to "Man" I did notice that the HW is ~slightly~ colder, but not by much.

Is the lever supposed to move on its own? I could have sworn I moved it once to midway and the next time I looked it was back to "Auto". There's no one apart from me who could change it.

Main thing is, I'm a happy bunny to have my downstairs heating back, at least until the boiler gets its annual inspection soon and I can speak with the engineer.

MM

How does one do that?

MM