a b ab valve and central heating

[Notebook64]

hot water working fine
turn on central heating switch and turn up roon stat and nothing happens.

looked at the honeywell motorised valve. It is T shaped. marked b, a and the one going down AB

If I move the lever manually to its futhest extent, then the heating and pump kick in. If I hook it on its latch, if just fails to kick in as if its coming back 2mm too much.
noticed 1 of the motor securing screws missing - might make a difference?

Have popped this head off to have a look at it.

what signals should I get on the wires - orange grey white etc when the heating is required and the stat closed etc

Have not seen the motor drive at all.

If i remove the power to the system, what reading should I get on the windings?

Thanks

 

[seco services]

calling for heating wall stat turned up.
hw off,satisfied. no resistance on the lever.
white 230v
orange 230v
grey 230v

 

[Notebook64]

calling for heating wall stat turned up.
hw off,satisfied.
white 230v
orange 230v
grey 230v

Got that
looked under the head and the gear doesnt look like it engages very well with the actuator part that turns. I buggered about with this a few years ago if i remember. also the double micro switch doesnt look the best.

If i select just water, what voltages should i get?

again any ideas on the motor windings
thanks

 

[seco services]

i never had the need to check motor windings.
but if only hw called for their will only be power on the cyl stat calling

 

[Notebook64]

i never had the need to check motor windings.
but if only hw called for their will only be power on the cyl stat calling

what colour is that?

Too late, the blooming micro switch just fell apart!!!

The valve I described, do I have to buy another honeywell, or will the local b and q do the job. is there only one type of unit available?

Nick

 

[D_Hailsham]

The valve I described, do I have to buy another honeywell, or will the local b and q do the job. is there only one type of unit available?

You can buy just the actuator (box on top with motor etc) or the complete valve. Honeywell are more expensive and better made. DIY sheds will probably stock just the complete valve, so try a plumbers merchant for the actuator only.

 

[Notebook64]

The valve I described, do I have to buy another honeywell, or will the local b and q do the job. is there only one type of unit available?

You can buy just the actuator (box on top with motor etc) or the complete valve. Honeywell are more expensive and better made. DIY sheds will probably stock just the complete valve, so try a plumbers merchant for the actuator only.

Any ideas on price?

 

[D_Hailsham]

Any ideas on price?

Complete valve about £65-£70
Actuator about £55-£60

Changing the complete valve would require a drain down. The actuator can be swapped without draining down.

 

[Notebook64]

Any ideas on price?

Complete valve about £65-£70
Actuator about £55-£60

Changing the complete valve would require a drain down. The actuator can be swapped without draining down.

Hi

I have a shut off valve left right of it and the down bit goes to the pump, and below this is a shut off valve - all manual
would it be ok to isolate it this way?

if i bought a b and q one, is the wiring standard?

Thanks

 

[MANDATE]

I've never seen a honeywell actuator head in any B & Q. In fact I can't recall seeing any actuator heads in B & Q. only complete valves.
The wiring is standard as far as I know. Wire from room stat to 'white wire' to drive motor to mid position.
Wire from programmer HW OFF terminal and wire from cylinder stat 'satisfied teminal' to 'grey' wire. This drives the motor from mid position to CH position.
The triggering of microswitch no 2 allows power out from valve via 'orange wire' to fire boiler.
'Blue wire' is neutral as normal.
'green/yellow wire' (if present) is earth as normal.

 

[spacethegas]

get a complete horstman & just change the head.

far cheaper than honeywell & far better guarantee.

 

[doitall]

Any ideas on price?

Complete valve about £65-£70
Actuator about £55-£60

Changing the complete valve would require a drain down. The actuator can be swapped without draining down.

Just to add to, not all honeywell valve can be changed without draining down, only the ones with a dimple on the top and 2 screws.

The 4 screw jobbies have to be drained out.

 

[ChrisR]

dimple

Pimple!

 

[Notebook64]

Bought a b and q jobby
wired it up as the original, only difference is that there wasnt an earth wire (plastic lid)
Isolated left, right and above andbelow the pump, that is a foot below the valve.
When removing the valve, water splashed over the terminal block containing lots of wires associated with this.
Have tried to dry these out with a hairdryer.
When I turn on all is well and I can hear a noise for a few seconds coming from that direction, possiblt the syc motor driving? ( I am downstairs ) However, when I turn on hot water or hw and ch the boiler powers up for 3 or 4 seconds and then the mcb trips supplying this. Any ideas ? could it be the water splashing over it?
Thanks
Nick

 

[MANDATE]

highly likely a 'short' has been created in the terminal box.
I would think a wire has been disturbed or put in wrong terminal.