WD51/2/1997 Chapter 5 : Fault FindingThe Keston 170 Condensing Boiler
Installation & Servicing Instructions
Page : 28
Contin ued o n sh eet 2
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no
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Continue d fro m Sheet 2
Is there 230V at val ve
Is there 230V at G as Low
Press . Sw itch
Faulty C ontrol B ox - R eplace.
Faulty G as V alve - Replace.
Faulty G as Low P ressure
Switc h - Repl ac e
Is there a spark present?
Is the H T v ol tage present at
top of igni tion electr ode?
Is the s park gap 4 m m ?
Faulty C onrtrol B ox - R eplace.
Replace/Adjust S park Plug.
Does the burner ignite?
Electrode Fault y - R epl ace.
R echeck gas output pressure.
Check HT lead is securely
fixed. C lean or replac e burner.
Does flam e stop after 5 - 10
s e conds ?
Is boiler earthed correc tly?
Are live and neutral supply
lines crossed at term inals L &
N ?
Faulty C ontrol B ox - R eplace.
Earth Boiler.
Correct W iring.