Worcester Heatslave 15/19

15 Dec 2011
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United Kingdom
Hi there, I have a Worcester Heatslave 15/19 oil fired combi boiler which keeps locking out. It either fires up but radiators don't get hot until boiler goes off or the radiators get mega hot and pressure gauge goes up high. It is serviced every year and was serviced two weeks ago. HELP PLEASE. Have bled radiators and bled oil through just to check.
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When you say 'locking out' - do you mean the burner lockout (red lamp on the controller with a repeater on the front panel) or the boiler overheat thermostat that you press up to reset?
With the pressure gauge showing 1 bar, switch the heating on - it should rise no higher than 1.5 bar. Excess pressure could indicate an expansion vessel issue - if the pressure exceeds 3 bar, the boiler vents water to outside.
John :)
Burner lockout keeps coming on, when reset it will fire up and heat up but pressure gauge rises from 1 bar to 2bar within minutes, boiler then goes to lockout. Friend suggested it might b one of the thermostates, could it b the heat exchanger?
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The burner lockout is a separate issue to the pressure build up. Pressure is probably due to expansion vessel problems; burner lock out is down to combustion issues; solenoid coil springs immediately to mind if it runs for aperiod before lockout.
I hate to say it - but you have had a pretty useless service done as you seem to have multiple faults on this boiler!!! expansion vessel clearly not checked, possible Diverter valve problem?? burner locking out???
we all get recalls occasionally but usually there is only one fault not at least three!! are you sure you want that engineer back! :eek: :confused:
The service engineer checked the expansion vessel (if thats the big red thing in front) and put air in it, he has serviced boiler every year for past 8-9 years (boiler is only 9-10 years old) and not had problems before. He is an old boy but capable (well I thought so). Not called him yet as got friend who worked for Worcester who said he will come look at boiler. Freezing butt off at the mo, not used to house without heat! :) Doesnt sound like this will b an easy fix! Thanks for all advice, will post results of postmortem once its done!

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