system wont turn off after thermostat replacement

[monafef]

today i fitted a new pump to my heating syetem which worked and tryed to change my old and damaged room thermostat a randall r3a (the old stat worked it was just craked) with a sunvic 9201, after trying unsuccessfully to change the stat and blowing the fuse in the switched spur i replaced the old stat and wired it as before, now i find my timer a randall wont function at all the clock is on but there is no system control and the system just runs of its own accord and the 3 way motorized valve has to be manually moved to heat either the hot water tank or the heating system.

i am wondering if i have blown my timer or somthing or if any one knows the answer.

i know i am a idiot

 

[electronicsuk]

As you say, you may have welded the contacts shut in the timer, and if you're 100% certain that the thermostat is wired up as it was originally then it seems very likely that this is the case. You should still have manual control of the system via the stat until you get a chance to replace the timer.

 

[bellairaphon]

Are you getting any power to the timeclock? the clock may just be the battery back-up.

Nath

 

[electronicsuk]

Are you getting any power to the timeclock? the clock may just be the battery back-up.

Nath

Presumably must be, if the system is running constantly.

EDIT: Good point - only just noticed the OP's comment about having to move the 3-port valve manually.

OP, when you say the system is running of its own accord, what is actually happening when you don't do anything manually to the valve?

 

[bellairaphon]

do'h!! i need to go to bed!!!

 

[monafef]

yer i getting the clock but it gos off when the power gos off so the back up battery is well gone but this thing is 24 years old now, but would the timer be the the whole reason as the motorized not moving automatic thorght the timer was just a on off button basically

 

[monafef]

in answer to your question eletronicsuk i have check again and the cylender stat is moving the valve when to tank is to temp guess i jumped in before the water heat up enough but the heating never shuts off and the time and the stat wont control it keeping the temp down at the min by turning the boiler stat right to the min, pump never stops till i turn off the switched spur.
now thinking i have killed my timer for sure.

dont know if this is relevant or helpful but
boiler economist myson 30/40
pump willo 6m head
valve draton
timer randall 103e
thermostat randall 3ra
cylinder stat honeywell 2

 

[electronicsuk]

in answer to your question eletronicsuk i have check again and the cylender stat is moving the valve when to tank is to temp guess i jumped in before the water heat up enough but the heating never shuts off and the time and the stat wont control it keeping the temp down at the min by turning the boiler stat right to the min, pump never stops till i turn off the switched spur.
now thinking i have killed my timer for sure.

Even if you had welded the timer contacts shut with the short circuit current, I would still expect you to have some control over the CH part of the system via the room stat.

You say the valve is moving as expected under control of the cylinder stat. Presumably there is no movement from the valve as the room stat is altered? If you can move the valve manually to a closed position and the system is still running, I would be suspecting a faulty microswitch inside the valves. However, I can't see how this could have been caused by you short-circuiting the thermostat. Is it possible these problems existed before but went unnoticed?

If you want to do any more fault finding at this point then you're going to need at least an electrical tester (either a multimeter or a 2-prong voltage probe) and some general electrical knowledge.