halstead ace faulty ignition

[primerumpsoton]

HI THERE
I HAVE A HALSTEAD ACE BOILER WHICH IS/WAS NOT FIRING UP ON WATER OR HEATING. THE WIRING IS SOUND AND IT HAS HAD TWO NEW BOARDS BUT STILL NOTHING. AS A LAST RESORT I INCREASED THE PRESSURE TO 3 BAR INCASE THE GUAGE WAS FAULTY BUT NO RESPONSE. HOWEVER WHEN I RELEASED SOME PRESSURE VIA THE PRESSURE RELIEF VALVE IT SUDDENLY STARTED UP AND RAN UNTILL I TURNED IT OFF AT THE MAINS AND DID NOT FIRE UP WHEN SWITCHED BACK ON. DOES ANYONE KNOW WHICH PART SENSES SYSTEM PRESSURE ON THESE BOILERS?
MANY THANKS

 

[gasmick2]

hi there is not a low pressure switch on these boilers, you only have a primary flow switch and a domestic flow switch, which are opperated by the diverter valve, you might have a problem with the diaphrams on the valve i would sugest you replace the diaphrams before going into other things
The boiler pressure should be set at 1.0 bar to 1.5 when cold

 

[primerumpsoton]

thanks for your help gas mick2

from what you said am i right in thinking the diverter would operate the micro switch on static pressure of 1 to 1.5 bar. at the moment at that pressure the pump does not start.

thanks again

 

[gasmick2]

hi the micro switches are opperated by the pump and the water pressure to the hot water side
i wonder if you have tried to press the overheat stat that is located under the boiler on the left hand side
there are 2 resets one is an ignition reset and this is on the front panel switch
The pump should opperate on any call for heat, heating or hot water
the overrheat stat must be manually pushed in till it clicks or you will get no mains to the pump and other components