Opop H 635 Manual page 15

Underburning / through-burning
flap in the underburning position
Primary air
1 Open the firing flap.
2 The underburning / through-burning flap can also be set to through-burning.
3 Set the flap to underburning before refueling the coal.
4 Please the firing flap immediately after proper firing takes place and adjust a correct volume of the
secondary air.
Hot Water Boiler Manual – Models H 635, H 650
Fig. 5: Boiler section during firing
15
Firing flap in the
firing position
Primary air inlet