INSTALLATION AND OPERATION INSTRUCTIONS
2-6
HC SERIES BOILERS HC 13-50, HC 23-84, HC 29-106, HC 33-124, HC 20-125, HC 33-160
o. DHW ECO mode Learning Days 3 days Range 1 to 10: Number of days the ECO mode
uses to learn the Tankless DHW usage habits.
Rolling counter. If set to 0 Opentherm will control
Eco Comfort Mode Occupied or Un-Occupied.
P Space Heating Delay after
the boiler reaches the target
temperature
2 min Range 0 – 15 min: The boiler will remain off for X
min to help reduce short cycling when the heating
load is smaller than the min ring rate.
P. Heat Exchanger Size Reference Model Dependent HC 13-50 / HC 23-84 = 24
HC 29-106 = 30
HC 33-124, HC 20-125 and HC 33-160 = 36
PARAMETER 1
SETTINGS
LOAD PRIORITY:
0 = HIGHEST
PARAMETER NUMBER 1: DETAILED DESCRIPTION
0 0 = Tankless DHW
1 = Space Heating
DC Models – Both Space Heating and Tankless DHW
• Internal Boiler Pump is enabled with a call for Space Heating
• Internal Boiler Pump is disabled with a call for Tankless DHW
1 0 = Indirect DHW Tank Sensor
or Aquastat
1 = Space Heating
HC Models – Space Heating and Indirect DHW Tank. DHW must be
turned on by pressing the Tap twice. Bottom LED must be ON.
• Aquastat or Sensor connected to X4.9 and X4.10
• Internal Boiler Pump is enabled for both Space Heating and for DHW
heating
• External Pump Terminals 4,5,6 (120Vac - 1Amp Max) enabled with a
call for DHW
2 0 = Tankless DHW DC Models – Tankless DHW Only
• DHW only, Space Heating Disabled
• Internal Pump disabled
3 0 = Space Heating HC Models – Space Heating Only
• Internal Boiler Pump is enabled with a call for Space Heating
4 0 = DHW Storage Tank Sensor
or Aquastat
1 = Space Heating
DC Models – Space Heating and Tankless DHW with a Storage Tank.
DHW must be turned on by pressing the Tap twice. Bottom LED
must be ON.
• Aquastat or Sensor connected to X4.9 and X4.10
• External Pump Terminals 4,5,6 (120Vac - 1Amp Max) enabled with a
call for DHW
• Internal Boiler Pump is enabled with a call for Space Heating
• Internal Boiler Pump is disabled with a call for Tankless DHW
• External DHW Pump is enabled with a call for Tankless DHW
5 0 = DHW Storage Tank Sensor
or Aquastat
DC Models – Tankless DHW with a Storage Tank Only. DHW must be
turned on by pressing the Tap twice. Bottom LED must be ON.
• Space Heating is disabled
• Aquastat or Sensor connected to X4.9 and X4.10
• External Pump Terminals 4,5,6 (120Vac - 1Amp Max) enabled with a
call for DHW
• Internal Boiler Pump disabled
• Internal Boiler Pump is disabled with a call for Tankless DHW
6 0 = Tankless DHW
1 = Indirect DHW Tank Sensor
or Aquastat
2 = Space Heating
DC Models – Space Heating, Indirect DHW Tank and Tankless DHW
• External Pump Terminals 4,5,6 (120Vac - 1Amp Max) enabled with a
call for DHW
• Internal Boiler Pump is enabled for both Space Heating and for Indirect
DHW
• Internal Boiler Pump is disabled with a call for Tankless DHW
NOTE: The control displays codes that include upper and lower case letter and a combination with a period after the letter.
Example: C, c., c are all valid parameter codes. When adjusting settings, double check that you are in the correct parameter.