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    • jammyberry
    • By jammyberry 12th Apr 18, 12:21 PM
    • 2Posts
    • 0Thanks
    combi boiler
    • #1
    • 12th Apr 18, 12:21 PM
    combi boiler 12th Apr 18 at 12:21 PM
    hi all,
    new to this so please bear with me. i have a glowworm 30cxi combi and here lies the problem, heating works perfectly every time on constant and timed, when heating is on hot water works every time, when combi has been off and is cold the hot water will not fire up the boiler, it tries to fire but fails and goes into f1 fault, most of the f1 faults are to do with gas faults but as it fires up for heating im assuming it cant be that. the diverter valve has been renewed, i was told it could be the pcb any thoughts would be greatly appreciated.
Page 1
    • tacpot12
    • By tacpot12 12th Apr 18, 2:36 PM
    • 1,687 Posts
    • 1,428 Thanks
    • #2
    • 12th Apr 18, 2:36 PM
    • #2
    • 12th Apr 18, 2:36 PM
    The manufacturers fault finding flow chart is available on Page 38 of the manual for the boiler; see

    This suggests that the flow sensor could also be a candidate for causing the boiler to not produce hot water when a hot tap is opened, but this probably won't produce an F1 error code...

    The F1 code means that the boiler controller has commanded the burner to light, but it has not lit within the normal time allowed for ignition. When a required parameter for the boiler to operate has not been met (now water pressure/fan not running/etc.) the controller would not even command the burner to light, so the problem is with the gas supply/gas valve or ignition.
    • jammyberry
    • By jammyberry 12th Apr 18, 4:43 PM
    • 2 Posts
    • 0 Thanks
    • #3
    • 12th Apr 18, 4:43 PM
    • #3
    • 12th Apr 18, 4:43 PM
    thank you for that, my only issue with it being anything to do with the gas was that the boiler lights everytime for the heating, that confused me so assumed if valve or ignitor had failed it would fail for both the heating and water and water fires boiler when heating is on
    Last edited by jammyberry; 12-04-2018 at 4:59 PM.
    • Wizzbang
    • By Wizzbang 12th Apr 18, 8:01 PM
    • 4,403 Posts
    • 10,010 Thanks
    • #4
    • 12th Apr 18, 8:01 PM
    • #4
    • 12th Apr 18, 8:01 PM
    What does this have to do with boosting your income? Surely this would get a better response in another group?
    Extra income since 01/11/12 34,952.54
    (Not inc coupons, yellow stickies, bank interest or loyalty rewards because I have better things to do than catalogue everything!) Swagbucks 2,650.00
    • Alex1983
    • By Alex1983 12th Apr 18, 8:44 PM
    • 927 Posts
    • 552 Thanks
    • #5
    • 12th Apr 18, 8:44 PM
    • #5
    • 12th Apr 18, 8:44 PM
    Are you sure that the boiler is firing for hot water when the CH is on and not just working for the heating? I would suspect the flow sensor is faulty but that wouldn't explain the F1 fault, maybe you have 2 issues.
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