Hi i hope you can help because i am stuck. I have put a new worcester 15ri on to an old system with a drayton mid posistion valve. The stat and programmer are honeywell 9000...2 channel. The problem is that when the hot water is on and its set to come on three times a day the rads also come on..............sometimes. So i have changed the valve body and head for the drayton Ma1 mid posistion valve (swap like for like). I thought the old one was letting by. I have also done the cylinder stat. The wiring is done by my sparks and he has gone over it a few times and come up blank. We dont do many y plans but we haven't had a problem before. I couldn't test the old system because the boiler was completely dead .The house was stood for a while but i am realy stuck,any help i have exhausted my brain and its playing on my mind allot.Its been fine for a week and had the dreaded call 30 mins ago.
Help with y plan please.
- Thread starter gasmanTim
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Could it be reverse flow caused by the HW cylinder return not being the last connection?
Are there three connections on the valve grey wire terminal (Grey, Prog HW OFF, Cyl stat SAT)?
Have you checked if the valve spindle moves easily? Remove actuator to check - it will rotate about a quarter turn. A little silicon lubricant may help.
Are there three connections on the valve grey wire terminal (Grey, Prog HW OFF, Cyl stat SAT)?
Have you checked if the valve spindle moves easily? Remove actuator to check - it will rotate about a quarter turn. A little silicon lubricant may help.
Any idea if this happened before? Is the cylinder return the last one teed into the boiler return?
Thanks for your replies realy kind.
im not sure on the reverse flow on the cylinder return because this problem is intermittent it only ever happens after 1500 hrs if at all.
The mid posistion valve body and actuator is brand new so i don't think its this. It moves into required posistion on demand.
As for the wiring i am not Part p and my sparks does this i will ask tomorrow.
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I couldnt get the old system up and running it was partially filled and the boiler was a real state ie control board hanging of etc.
Sorry ,do you mean part of the heating circuit plumbed in to the cylinder return .There has been an extension added about ten years ago i dont know by who . I will say it only affects upstairs from what i gather.
I see where you are coming from but this would be periminant and not happening now and again.
The mid posistion valve moves over on demand and i can fell the pipe on the clinder flow warm as the valve moves over and the return on the cylinder also starts to warm .Same goes for the valve on heating only.
If the cylinder return was before the new rads i m screwed arent I . Floar boards up etc .
Thankyou very much. I will try this tomorrow.
Hi and good morning. I have been back to the property and fired the hot water up with temperature probes on the flow and return on the offending rads.............monitored temperature for about 30 minutes and there was no change in flow or return.
Heating on flow gets hot with return being cooler and all rads getting up to temp.
My spark went over the wiring again for maybe the 4th time . ALL GOOD.
I cant replicate the fault in any way. I have changed the hot water times for twice a day ,instead of all day. Could it realy take all day for a new valve body and actuator to let by or is it that the timer could be faulty....they are both new.
Heating on flow gets hot with return being cooler and all rads getting up to temp.
My spark went over the wiring again for maybe the 4th time . ALL GOOD.
I cant replicate the fault in any way. I have changed the hot water times for twice a day ,instead of all day. Could it realy take all day for a new valve body and actuator to let by or is it that the timer could be faulty....they are both new.
I know you said the wiring has been checked but is the hot water off connected to the programmer ? when this wire is missing the 3 port can sit on central heating when hot water is called for, good luck finding the problem.
Can you post a clear pic showing the wires in the wiring center and programmer.
Did you just change the boiler.
When you say the offending rads, they don't all get hot when they shouldn't ?, what is the location of the problem rads.
Post some system information, pipe sizes etc
Where are you located.
Did you just change the boiler.
When you say the offending rads, they don't all get hot when they shouldn't ?, what is the location of the problem rads.
Post some system information, pipe sizes etc
Where are you located.
doitall";p="2548335 said:Can you post a clear pic showing the wires in the wiring center and programmer.
If i get called again i will be sure to post a pick of the wiring centre and programmer.
Did you just change the boiler.
Boiler has been the only thing changed and the wiring centre was rewired to the honeywell book. Again i cant help with the electrics as my sparks does them. He uses bootlace ferulls so he must be good..He is very good does allot of commercial etc
Have replace valve body and actuator and new cylinder stat.
When you say the offending rads, they don't all get hot when they shouldn't ?, what is the location of the problem rads.
The rads that come on are 3 upstairs but i have yet to witness this first hand.
Post some system information, pipe sizes etc
It is vented cylinder with old grunfoss pump,New drayton mid posistion valve with a centre brand cylinder stat.
The boiler is a worcester 15ri the programmer and room stat are honeywell 2 channel (ct9000) .
Now the pipe sizing is a bit more difficult as it is existing but as the house has been extended i think the upstairs is undersize because when i put the new gas main in most of the flow and return was 15mm. Off the cylinder is 22 mm and that goes for the boiler flow and return aswell . All drops are in 15mm so no smallbore stuff. Its a 2 bedroom house that used to be a 3 bed but the have added more radiators.
Flow and return off the boiler are insulated as far as i can go , the condensate is internally run to the soil stak and bossed in. Complete new gas carcass 28mm off the meter down to 22mm to the boiler (its a bit of a long gas main and powers a hob and gas fire)
Boiler commisioned, gas rated and working pressure all fine.
I am located in the worcester area.
Thanks for your time and help.
Hi thanks for the reply. I am sure the valve is working as on the drayton i can see it slide from dhw to mid to heating. The sparks testing is confirming this with his testing equipment.;
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