Bosch Worcester Danesmoor Utility Regular ErP+ 12/18 - Page 54

Fault finding and diagnosis
Greenstar Danesmoor Utility
ErP+
and Utility System
ErP+
- 6 720 821 720 (2018/04)54
5 Burner does not fire, burner locks out after 25 seconds from motor start? Yes Go to line 5a
No Go to line 6
5a Burner fires when the photo cell is covered? Yes Remove extraneous light
No
Go to line 5b
5b
Photo cell voltage ≥ 3.8V in the dark and
approximately 0V in the light?
Yes Replace the control board
No
Replace the photo cell
6 Pump washing pressure 1 to 2 bar? Yes Go to line 7
No
Go to line 6a
6a
Pump pressure more than 6 bar? Yes Replace oil pump
No
Go to line 6b
6b
Check oil supply to the pump, if oil supply is OK Go to line 6c
6c
Drive coupling broken? Yes Replace drive coupling
No
Replace oil pump
7 Ignition spark present? Yes Go to line 8
No
Go to line 7a
7a
Are ignition leads and electrodes OK and set correctly? Yes Replace control box
No
Replace/reset electrodes/ignition leads
8 Solenoid coil releases working pressure? Yes Go to line 9
No
Go to line 8a
8a
Does burner light or green 0.5 seconds ON/red 0.5 seconds ON
before lockout?
Yes Go to line 5a
No
Go to line 8b
8b Contaminated fuel filters? Yes Clean/Replace filters
No
Go to line 8c
8c
Coil lead OK Yes Go to line 8d
No
Replace solenoid coil lead
8d
Solenoid coil resistance 90 to 110 Ω Yes Go to line 8e
No
Replace solenoid coil
8e
After 15 seconds from motor start, 25 to 30 Volts d.c. to solenoid
coil? (coil connected)
Yes Replace oil pump
No
Replace control box
9 Air set correctly? Yes Go to line 10
No Adjust combustion air settings
10 Does the burner light?
Flue damper fitted? (if required)
Yes Go to line 11
No
Go to line 10a
10a Is the nozzle atomising the fuel? Yes Go to line 11
No Go to line 10b
10b Nozzle new? Yes Go to line 10c
No Replace nozzle
10c Check oil pipe from pump to nozzle holder Clean/ replace pump and fuel line filters
11 Combustion head set correctly? Yes Go to line 11a
No
Reset combustion head
11a Flame goes out then re-lights Yes Go to line 11c
No Go to line 11b
11b Boiler or flue blocked Yes Clear blockage
No Go to line 11c
11c If balanced flue, remove the snorkel and test - now OK? Yes Go to line 11d
No Go to line 11e
11d Balanced flues can recirculate gases causing recycling Check the flue position and seals
11e Photo cell voltage ≥ 3.8V in the dark and
approximately 0V in the light?
Yes Replace the control box
No
Replace photocell
Line Check Action
Table 14