Cost of fitting a Honeywell 3 port valve to pressured system?

[Caesar]

Hi All

Can anyone provide a ball park figure for replacing a honeywell 3 art valve to a pressured system? When hot water is called radiators heat up no hot water. Moved the lever on the port but absolutely feels lie is not connected to anything powered on or off!

Many Thanks.

 

[Nige F]

Could just be the motorhead that needs replacing . £80 plus the head ( just did my neighbour's but the head was in my garage and I charged him £20 total) Probably a lot more if you're in Pimlico.

 

[Mottie]

I had a 3 port valve fitted to my conventional heating system. When I had it converted to a sealed (pressured) system I was told they are not best suited to a sealed system so two 2 port valves and an automatic bypass were fitted.