Switchmaster three way diverter valve Replacement

[Mik]

Hi again. I have just been getting advice on replacing a radiator on my sons system only to have a fuse blow on my system. It looks like the tree way diverter valve is shot. I replaced fuse and when I went to cylinder cupboard i noticed that there was a small ammount of moisture around the base of the diverter( not the compression fittings) also the diverter responds to the cenntral heating commands but then without change in command the diverter goes around the clock to come back to the central heating and hot water command, where it was initially. I am having trouble removing the cover. The valve is a blue switchmaster diverter some 30 years in the system and I assume not replaceable. Any initial advice please. If the opinion is that it is shot could and advice is replacement is there one that might go in on existing unions. It has been put in right near the floor and very little room to manouvre. I am quite competant on tha piework aspect if needs to be chaged. Not my day. Mik

 

[DaveTidy]

Hi
The wiring is non standard and the pipework would need altering so there is no direct replacement. I would get a Gas Safe Engineer to call as they will know about the wiring modifications.

 

[Citiheat]

Hi Mik. The Switchmaster has a different pipework configuration to any other valve, so you will have to replace the body as well. It was obsolete many years ago. Temorary fix until you have time. Remove the actuator (The blue box) by pulling it off. It is held on by spring clips. Put no pressure on the pipework, this could be fatal and very wet. Fix the box to a dry bit of pipework. turn on the heating and rotate the valve spindle carefully until heat travels through all three pipes (inlet, water and heating). This will now work, after a fashion, with limited thermostatic control. If one circuit is on, so will the other be on. When the water is hot, turn it off at the programmer and you will have thermostatic control of your heating and vice versa.

 

[Mik]

Thanks again for everyones help.

The unit has started up ok this evening with small drips around unit. I think it must have been small leak for some time but when the heating comes on the high local heat dries up the evidence. Any way I will hopefully wait until a bit warmer climate and changethe lot. I will look at wiring arrangement on internet and choose a new diverter that has the simplest and nearest arrangement. I can see my way around these type of electrics as I did some similar work before I retired. Anyway many thanks. The greatest gift yuo can give anyone is time. sincerely Mik