DIYbanter - View Single Post - BLOWING FUSES PART 2 !!!!!!!!!!!!!!!!!!!!!!

wrote:
thanks to all the constructive info
instead of replying to you all individually, i started this new thread.

husband home
heres what hes done so far

the first controller is an 'ACL lifestyle model LP522'
ACTUALLY FLSHED OUT WHEN FIRST NEW FUSE WAS PUT IN
it was then replaced with 'Siemens RWB 9'
WHEN FIRST FUSE PUT IN IT WORKED,THIS WAS ABOUT A MONTH AGO.
OBVIOUSLEY DUE TO THE 'HOT WEATHER' THE HEATING HAS NOT BEEN USED MUCH,
AND OUR HOT WATER IS SUPPLIED BY EITHER IMMERSION OR GAS AND IT WASN'T
NOTICED UNTIL A FORTNIGHT LATER, THAT THE CONTROL BOX WASN'T WORKING
AGAIN
I DISCONNECTED THE PUMP, FROM THE SYSTEM AND STILL THE FUSE BLEW
RECONNECTED THE PUMP AND DISCONNECTED THE VALVE,STILL THE FUSE BLEW,
GOT THE HOT WATER TO FIRE,THE PUMP WAS RUNNING OK,SMOOTH AND USUAL,
WHEN THE HEATING WAS TURNED ON,THE FUSE BLEW AGAIN,
I DISMANTALLED THE MOTOR UNIT ON THE VALVE,SO THE VALVE COULD BE
SHIFTED MANUALLY,GOT THE HT WATER FIRED AGAIN, MANUALLY SHIFTED THE
VALVE,AND GOT THE HOT WATER TO RUN THE HEATING SYSTEM,AS I WAS TOLD
THERE COULD HAVE BEEN POSSIBLY AN AIRLOCK CAUSING THE PUMP TO STALL,
BUT DOING THIS PROOVED THERE WAS NO AIRLOCK IN THE SYSTEM,
WITH THE VALVE STILL SWITCHED TO CENTRAL HEATING SIDE I TRIED TO FIRE
THE CENTRAL HEATING ON THE CONTROL BOX, AND THE FUSE BLEW AGAIN,
THE NEXT THING I DID WAS TO DISCONNECT THE THERMOSTAT,TRIED IT AGAIN,
AND THE FUSE BLEW AGAIN,
THE BACK PLATE HAS BEEN CHANGED ON THE CONTROL BOX,STILL BLEW THE FUSE,
THEN THE FUSE WAS BLOWING WITH ALL SWITCHED OFF ON THE CONTROL BOX,
PURCHASED ANOTHER CONTROL BOX,STILL BLOWING FUSES

SO THANKS PEOPLE FOR ALL THE GREAT INFO SO FAR, IF THIS HAS ENLIGHTENED
ANY OF YOU FURTHER
WE WOULD APPRICIATE ANY FURTHER ASSISTANCE
JO

Jo, from what you say it looks as if the problem is in CH thermostat, CH
divertor valve or the wiring to them, but chief suspect is still the
changes you have done. Have you drilled a cable or shorted one in
fitting the new timer? Are you sure you've connected the new timer
correctly?

If that's not it then it looks as if you need to go right back to basics
and test it with a neon tester if you've nothing more sophisticated.
You'll also need an understanding of the circuit and wiring plan. This
is how I'd go about testing my system, but you might need to interpret
and adjust to suit your plan. In disconnecting wires insulate then with
tape temporarily and LABEL THEM!

0. If you unplug the timer does it blow the fuse? If so then problem
in fuse/wiring to the timer. You have got this far.

1. Can you connect the timer to the mains but with the 'heating' and
'water' circuits disconnected? You might need to extend cables with
wire and connector blocks, or even connevt it to a 13A plug (with care).
Is it okay? Does the clock run? Does it have little lights or
indicators which come on when the water/heating is demanded? Do the
outputs switch (use the tester) when you expect them to? If not then
you have a faulty timer.

2. Next connect the CH thermostat but with its output disconnected.
Check the thermostat output with a neon tester (either on the device or
in the wiring box). Does it light up only when the timer demands CH and
the temperature is low?

3. If you have electric divertor valves, connect the CH one to the
thermostat but disconnect its switched output. Does it activate
(whirring noise) when you require heat? Does the output connection
from it go live?

4, 5 repeat 2 & 3 but for cylinder thermostat. (assuming stored water
cylinder). You seem to not have a problem here.

6. Now connect the pump to the divertor valve output, Does it pump if
you demand heat?

7. Now connect boiler - does it work now?

Good luck.
Phil