Olsen OLSSC-075, Installation, Operation & Maintenance Manual

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User Interface Display
Explanation
CH Settings
C H S E T T I N G S
C H m o d e M O D E : 1
C H w i t h t h e r m o s t a t
▼
4. Central Heating (CH) modes available:
CH Mode = 0 ‘CH with Thermostat’ •
Boiler will attempt to satisfy CH demand while CH •
thermostat input is closed.
Boiler will modulate its fi ring rate to maintain CH set
•
point and match system heat load.
CH set point adjusted in ‘Settings’ submenu under ‘User
•
Menu’
CH Mode = 1 ‘CH with Thermostat and Outdoor Reset’ •
Boiler will attempt to satisfy CH demand when CH •
thermostat input is closed.
Boiler will modulate its fi ring rate to maintain CH set
•
point and match system heat load.
CH set point calculated as function of outdoor
•
temperature using outdoor reset curve. See fi gure A-2
• CH Mode = 2 ‘CH with Full Outdoor Reset’
Boiler will permanently attempt to satisfy CH •
demand.
CH thermostat input is ignored.
•
CH set point calculated as function of outdoor •
temperature using outdoor reset curve. See fi gure A-2
CH Mode = 3 ‘CH with Permanent Demand’ •
Boiler will permanently attempt to satisfy CH •
demand.
CH thermostat input is ignored.
•
CH set point is adjusted in ‘Settings’ submenu under •
‘User Menu’
Note:
• Once CH demand is satisfi ed (i.e. CH thermostat opens or
boiler determines its minimum fi ring rate exceeds system
heating load):
Burner shuts off, boiler enters post purge. •
CH pump continues to run for 30 seconds. •
Control will wait until Anti-cycle time of 180 seconds •
elapses before boiler fi res again. Prevents short-
cycling.
• The internal heat exchanger pump is energized anytime demand
exists regardless of Pump Mode setting or type of demand (CH or
DHW).
APPENDIX A - CONTROL MODULE