Honeywell 3 Port Valve Faulty

[TerryWaite]

I have a faulty 3 port valve on a y plan when there is a demand for hot water the boiler fires, when there is a demand for heating, nothing, i am fairly certain its the 3 port valve, how do you test whether its the motor which has gone, the switch inside it or the spindle has seized? i.e how do you tell whether its a new motor, actuator, or complete valve you need?

and also the wire just goes to a single back box in the wall with a blanking plate on, not a proper 10 way box, is this common? and will isolating the boiler fused spur kill the electricity to this or will it have a seperate supply?

advice much appreciated.

 

[lance]

You forgot your life story.

 

[TerryWaite]

sorry?

 

[tamz]

It sounds like you have not got a lot of experience with electrics. Get someone to help you with this.
The valve is probably ok but the wiring may need adjusted. You (or someone else) needs to test this.

 

[TerryWaite]

yes youre right not that much experience but i can safely isolate/continuity test, is the wiring aspect hard?

 

[plumbqate]

wiring diagrams are on the Honeywell site. then a multi meter and away you go. But as the post above says only if you are experienced in this kind of thing.

 

[Best]

Wish there was an easy way. I have opened the head & checked motor. The spindle is normally easy to check if it is a bit tight or slight weeps at it, by removing head.

 

[billybob150811]

the spur to the boiler wont isolate the electrics. i cant see your house and i dont care about that i,m simply saying better safe than sorry but some boilers the spur is twin and earth and the feed for the pump is from the wiring centre the dhw wont maynot require power to the three port it comes via the cylinder stat i hate to sound so know all and old fart that isnt how i mean it but i,d make certain you,ve isolated

 

[tamz]

is the wiring aspect hard?

If you don't understand how it works yes. Depends on how it has been wired how easy it is to trace.

 

[TerryWaite]

You forgot your life story.

just got on to that m8, bit slow there, thats not my real name, merely an alias in honour of him

 

[TerryWaite]

so the boiler spur wont always isolate the entire wiring centre?

 

[tamz]

so the boiler spur wont always isolate the entire wiring centre?

It should only be fed from one supply but never trust heating wiring.

 

[billybob150811]

some times the main supply is in the airing cupboard with the wiring centre and the the boiler spur is supplemental and some times its not tamz is bang on it shold come from one supply but treat all electrics with a certain distrust

 

[TerryWaite]

Thanks very much, i will make sure it is all safely isolated before I work on it. Going on the Honeywell course on tues, cant wait, hopefully this will be as good as everyone says!

 

[dontknowitall]

so the boiler spur wont always isolate the entire wiring centre?

No.

Different boilers, different electricians, different plumbers, diyers, etc

This means that unless you like spikey hair you MUST isolate the electricity and know how to test to see if it's isolated or not. This comes in advance of doing anything with the wiring.

 

[TerryWaite]

yeah wouldnt mind spikey hair, i wouldnt want to melt any of my nice shiny tools though

 

[Best]

I worked on wires coming from a spur switch ( all done by a young spark) & discovered he had put the wires all in one side of the switch! That meant the spur was only a connector & the wires were live if the time clock turned on. Not a bright spark I guess! Lesson is don't assume power is off.

 

[gasmanrob]

Always best to get someone in if your not 100% confident i know electricians that cant get there head around wiring centers, the fused spur dosent always isolate the controls as people add on and adapt systems all the time, there are a few boilers that use two fuse spurs for example. im sure people would like to guide you but wouldnt want to mis direct you and leave you with an irregular heart beat or worse!! a simple test would be to put heating demand on at the time clock (no hot water) and room stat up high, externally on the 3 port head (silver box) you will find a small lever gently push this and see if the motor takes over if not it will return back to its start once you let go, if this fails push if a second time firmer and faster you should hear the pump kick in for a split second if that happens the switch is ok but motor is likely to have given up the ghost but youve done all you can time to pick up the phone and get some one in, better to pay a reasonable sum for a job well done then go in blind and possibly make things worse!! or harm your self.

 

[TerryWaite]

naughty that

 

[TerryWaite]

thanks rob, if i do the lever test and the pump doesnt kick in, then am i right in assuming its most likely either the switch thats gone or the valve spindle seized. is there any way to prove which one of these it is, if its the switch you can get away with just replacing the actuator cant you?

 

[gasmanrob]

If the lever moves its unlikely the spindle is stuck, and if you dont hear the pump kick in then there is every chance the actuator will need replacing, but again this all depands as to the pump being connected at the wiring center and not supplied via the boiler for pump over run. (see how this can become complicated to explain on a forum). also worth mentioning only replace the honeywell actuators secured on with 2 screws at diagonals to each other if you try to replace a honeywell actuator secured by a screw in each corner you will find your self very wet!!!:frown2:

 

[TerryWaite]

so not straightforward at all unless youre experienced, i reckon i can change one with the screws in each corner without draining, i can get a valve on a 4 inch water main without turning the water off, im an expert

 

[TerryWaite]

changed that valve, all went well, no problems, thanks for everyones help. Honeywell course was great too!