Worcester Heatslave 20 / 25 repeated lockout after only a minute or so running

[Timbo42]

This is more for information, since I have solved the problem today.
My Worcester Heatslave 20/25 Oil fired Combi would fire up correctly but after only a minute or so ( longer from cold ) would shut down and go to lockout. Turning down both HW & CH thermostat controls would put all the facia and control box lockout lights out, but unit would not restart until control box button pressed. Then it would fire up as normal run for a minute or so and lockout again etc etc.

Fault traced to coil on Danfoss BFP fuel pump. Presumably heating up and losing it's "grip" on the fuel valve. Before diagnosing this I was on the point of calling in engineer or just replacing control box so problem fixed for £35.00 !

Hope this helps someone out there !

 

[kimbo]

Common problem on these £35 is a bit steep though for a coil

 

[SimonG]

£35 is very steep for a Danfoss coil.

 

[quality]

Glad you fixed it

 

[Timbo42]

It may be steep, but still a small price to pay for marital harmony after a week of me head scratching and no HW or CH ! Ha Ha !

 

[SimonG]

very true............

 

[Dulux]

Thanks for this information, Ive just had the same problem. It was hard to diagnose at first as my fuel tank was low when it first loced out and I assumed it was dirt or air in the system. After pressing the lock out button it would run for 10 minutes from cold but would lockout within 2 minutes when warm. Purchased new coil: Danfoss 071N0010 from Plumb Center for £25.41 + vat,fitted yesterday, boiler seems to be working OK