HTP sequences of operation

7 sequences for HTP equipment: what the unit does, step by step, with the timings. Pick the equipment type, then the mode.

Boiler (7)

Ignition

• Ignition retries and lockout
  Elite EL

Heating

• Central heat call
  Elite EL
• Outdoor reset and warm weather shutoff
  Elite EL

Domestic hot water

• Indirect water heater call
  Elite EL

Pump/purge

• Pump service mode
  Elite EL

Standby/shutdown

• Standby and over-temperature protection
  Elite EL

Other

• Cascade operation
  Elite EL

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.