boiler make & model
gas council number [if possible]
F28 normally refers to 5 failed attempts to light boiler
boiler goes into lockout
can only be manually reset by pressing flame failure button
if you dont know where the reset button is refer to user manual
F28 flame failure
there can be several reasons for flame failure
gas supply problems
[are the other gas appliances in the property working ok
if not ok check the gas meter, is it a token meter
does it have credit on it]
ignition problems
[spark generator
ignition electrode
gas valve]
zero pressure
vaillant boilers normally display F22 fault code when zero pressure
if you have never topped up the pressure before on the boiler & are unsure which valves to turn refer to
youtube
how to fill vaillant ecotec combination boiler displaying F22
priority to top up boiler first
see if it clears F28 fault
manwithnoname
April 2012