Control system sequence
Status OK Sub-status Operation
3 / 4
30
Burner lit and free modulation on the boiler instruction
31
Burner lit and free modulation on a limited instruction, equal to a return temperature of +30°C
32
Burner lit and free modulation on the boiler set point but restricted on the control panel
¼
See menu #PRIMARY LIMITS: ""Professional" settings", page 82
33
Burner lit and descending modulation following too large a rise in temperature on the exchanger (4 K
in 10 seconds)
34
Burner lit and minimum modulation following too large a rise in temperature on the exhanger (7 K in
10 seconds)
35
Burner off following too large a rise in temperature on the exchanger (9 K in 10 seconds)
36
Burner lit and ascending modulation to guarantee a correct ionization current
37
Heating: Burner lit and minimum modulation after a burner start-up lasting 30 seconds
DHW production: Burner lit and minimum modulation after a burner start-up lasting 100 seconds
38
Burner lit and modulation fixed higher than the minimum after burner start-up lasting 30 seconds, if the
burner was off for more than 2 hours or after powering up
5
40
The burner will stop
41
The fan switches to post-sweeping speed on the burner
42
The external gas valve closes
43
Post-sweeping
44
Stop fan
6
60
Post-operation of the boiler pump
61
Stop boiler pump
62
Close isolating valve
63
Start anti short cycle
8
0
Awaiting burner start-up
1
Anti-short cycle activated
9
--
Blockage detected
10
--
Lock-out
16
--
Bleed
17
--
Antifreeze protection
8. Troubleshooting
MCA 15 - MCA 25 MCA 25/28 MI
128
29/04/2010 - 300022146-001-B
