New Glow Worm Ultracom 18sxi wont switch off !!!

quattro64 · Dec 31, 2010

Just wondered if anyone had experienced anything like this before I call Glow Worm on tuesday. Have just fitted new Ultracom 18 sxi system boiler to an existing system. System is Y plan and have also fitted new Honeywell 7 day programmer and roomstat - although this problem is not related to external controls. Calling for heat or hot water or both and everything works fine however if HW and CH are switched off at programmer the boiler still stays running. Putting a meter on the switched live at the boiler shows no voltage so the controls arent calling. I have even removed the switched live wire from the boiler so that it just has the power supply, switched the boiler back on and after a few minutes it will fire up and stay burning at a low rate. the boiler is inside the house and there is no frost stat wired up.??
Many thanks

gasmarc · Dec 31, 2010

you may have your permanent live and switch live the wrong way around ,good luck

Billy Bob Bob · Dec 31, 2010

i would tend to agree,hope you sort it sounds like the boilers getting 240 from somewhere

quattro64 · Dec 31, 2010

Thanks for replies, I did check that along with polarity - even removed the switch live from the boiler!

gasmarc · Dec 31, 2010

its a nice easy one to sort out ,it only took me about a day and a half to sort out as my wiring skills are not that good and my mate who has a failed physics degree wired the bloody thing up wrong lol good luck

clydey · Dec 31, 2010

according to the manual there is a built in frost protection device that operates according to the temp of the water (8 deg) operating the pump and eventually the burner if temp not met irrespective of any external controls
hope this helps

l11tul · Jan 1, 2011

have you left your 3 port valve manually open after your flush

prs1 · Jan 1, 2011

There is a link(for 24v roomstat) in the left hand side on the pcb for low volt controlls which needs to be removed if being fitted to an existing system.
They neglected to put this in the mi's.
Remove and all will be well!

quattro64 · Jan 1, 2011

prs1 said:
There is a link(for 24v roomstat) in the left hand side on the pcb for low volt controlls which needs to be removed if being fitted to an existing system.
They neglected to put this in the mi's.
Remove and all will be well!

Many thanks, that sounds exactly the problem and would give the symptoms i'm experiencing - I didnt think to check for a loop on the low voltage side and the MI's do not mention this. Will be going back to the clients on tuesday and will confirm findings.
Cheers