Observation:
| Isolate Mains Power to appliance as per TOP's P4 |
Only CH operation is affected by JP2
JP2 not fitted.
If a jumper tag has not been fitted at JP2 on the PCB, CH operation is 2 minutes at minimum burner pressure (burner pressure will go to full rate briefly before dropping down to minimum), then 15 minutes at 75% of maximum output if required, thereafter the appliance operates on maximum output or begins to modulate until the desired temperature setting is reached, anti-cycle time delay, set at 3 minutes.
| 25HE | 29HE | 35HE | MAX burner pressure (mbar) | 9.4 | 9.2 | 10.1 |
| CH MIN burner pressure (mbar) | 3.5 | 2.7 | 2.1 |
| DHW MIN burner pressure (mbar) | 1.5 | 1.2 | 1.0 |
JP2 fitted.
If a jumper tag has been fitted at JP2 on the PCB, the operation at minimum burner pressure is reduced from 2 minutes to approximately 5 seconds (burner pressure will go to full rate briefly before dropping down to minimum), the 15 minute operation at 75% output is cancelled and the 3 minute anti-cycle is also cancelled.
