Service – Lochinvar Knight Heating Boiler 81-286 User Manual

Page 12

Advertising
background image

1

Service

12

Service Manual

1

Service

Table 1-1 (continued from previous page) Sequence of Operation

OPERATION

DISPLAY

8. If the space heating call for heat is active, and the tank thermostat

or sensor starts a DHW call for heat, the boiler will switch to the
DHW mode. If programmed for normal DHW operation (not as a
zone), the DHW pump will turn on first, then the boiler pump will
turn off 2 seconds later. This will divert the boiler’s outlet water
from the heating system and send it to the tank coil instead. The
control will then modulate to maintain the outlet temperature to
the DHW boiler set point.

9. If the boiler is not part of a Cascade, and both the space heating

and DHW calls for heat remain active long enough, the boiler will
switch back and forth between the two heating modes until one
of them is satisfied.

10. Once both calls for heat are satisfied, the control will turn off

the burner. The blower will continue to run during the postpurge
period.

11. Any pumps that are running will continue to run for their

respective pump delay times before turning off, unless
programmed to remain on continuously. A 60 second anti-cycle
period will start, which will delay any new call for heat until it
times out.

12. In Standby, ready to start a new cycle.

Advertising