Three Port Valve

[alhay]

Please can anyone explain why a Danfoss 3 port valve stays energised on the central heating position, if that was the last call for heat, until the next call for heat, either hot water or heating, when this may not be for several hours. Why does it just not switch off and return on the spring until heat is required next time?

 

[ChrisR]

Cos it still has power on it. There's a good explanation in this forum, but will take some finding.

 

[wilhelm]

http://www.diyfaq.org.uk/plumbing/plumbingpage2.html#midposition

 

[ChrisR]

The one here was better - will try to find it.

 

[ChrisR]

found it:
//www.diynot.com/forums/viewtopic.php?t=8369&highlight=port+valve

 

[alhay]

Brilliant, thanks for the explanation. I am an engineer but I work in a different field, operating theatre anaesthesia equipment, so it is very important to me to know how things work!