motorised vale faulty? backread signals?

[loveplumbing]

Hi there

I have a problem with my hot water and heating where none of them come on

I have tested both my cylinder thermostat and my room/wall thermostat and both of their common terminals and call terminals are live when programmed on and turned up to max settings.

so now i am going to test my motorised valve and the orange wire should be live to start the pump and boiler

i have been reading a book over the past 6 months about central heating and it says that sometimes you can get backread signals from a motorised valve when testing for voltage

is this the case?

how can i prevent backread signals and be 100& sure it is the motorised valve which is faulty?

from what i know and have learned: white wire will be live (for heating calling) and this in term makes orange live (when the motor inside motors across).

for the hot water: orange becomes live also when calling for heat (as it is joined to the cylinder call terminal also)

so to summarize
if my cylinder call terminal is live but orange of the motorised valve is not live (when calling for heat to the hw cylinder) and white wire of the motorised valve is live (when calling for heat) but orange still isn't live, this means the valve is def. faulty...

i would just like some re-assurance from anyone know knows...

the backread signals part made me think i have done something wrong or may not be 100% right in my elimination/fault finding..

thank you anyone who can help/advise/comment..

 

[seco services]

if its a mid position valve calling for hw dosen't have nothing to do with the valve the cylinder stat wire gos to the pump/boiler.

 

[loveplumbing]

yes i know that is right - but for heating, orange should be live as well as white (as it will be calling for heat and thus making orange live to switch on power to pump and boiler).

 

[seco services]

yes

 

[loveplumbing]

ok thanks for confirming that with me.

so if white is live but ornage is not, then the valve motor is faulty.

i might just replace the whole valve to be on the safe side and then it'll all be nice and new.

but what about the backread signals situation? is this true or do i need not worry too much about this? thankyou for your replies by the way, i am greatful to you.

 

[seco services]

if white live and orange not the motor may just have gone.
push the lever on the end of valve across and clip it in to its lock position.
do you get live ?

 

[loveplumbing]

oh!! yes when i push the lever across and hooked it in position the pump and boiler started to work!! does this mean the motor is def. worn then and obviously not motoring across and switching on the pump and boiler automatically?

new valve?

 

[seco services]

yes correct just change the motor two screws two wires.

http://www.pulsardirect.co.uk/plumbing-supplies/addtocart.asp?ProductCatId=1000697&ProductSubId=99

 

[loveplumbing]

thanks for your help. i will do that. i've got another question i'd like advice on if possible but it's a different subject so i'll post a new topic! (v simple though probably for you)!!

thanks again.

 

[steved101]

the only way you may get backread signals is if you test them with your meter without properley disconnecting each wire from the junction box / centre.