Description
The Armstrong Furnace R37520B009 SPST Rollout Switch M/R is an electrical control component used in systems to monitor normal heat conditions within the burner compartment. It is installed on gas furnace assemblies where it detects excessive temperature rise associated with flame rollout events near the burner space. When the setpoint of 300F is reached, the switch opens the electrical circuit, interrupting gas valve operation in HVAC systems. In residential and light commercial heating systems, it operates as part of the furnace safety chain alongside other limits and controls. It is used during service repairs and replacements to restore proper safety operation in furnace models.
