A-90 Pressure Switches 2013 TSA Meeting UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Single Stage Pressure Switches Single stage furnaces have 2 pressure switches Housing Pressure Switch (HPS) Tapped into Inducer Housing Connects electrically to the CPU of the furnace control board Collector Box Pressure Switch (LPS) Tapped into Collector Box Connects electrically to GVR via furnace control board The HPS has a lower set point than the LPS HPS functions as a blocked vent switch LPS functions as a blocked drain switch UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Single Stage Wiring Diagram Refer to the legend HPS Inducer Housing Pressure Switch, SPST (N.O.) LPS Collector Box Pressure Switch, SPST (N.O.) UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Single Stage Pressure Switches UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Single Stage & Two Pressure Switches UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Two Stage Pressure Switches Two stage furnaces have 2 pressure switches Each switch has its own reference point Not connected by pressure internally High Heat Pressure Switch (HPS) Tapped into Inducer Housing Connects electrically to high heat stage of gas valve Low Heat Pressure Switch (LPS) Tapped into Collector Box Connects back to GVR contact via furnace control board The HPS has a lower set point than the LPS UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Two Stage Wiring Diagram Refer to the legend HPS High-Heat Pressure Switch, SPST (N.O.) LPS Low Heat Pressure Switch, SPST (N.O.) UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Two Stage Wiring Diagram UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Modulating Furnace Pressure Switches Modulating Furnace uses 3 pressure switches Low Tapped to Medium & High pressure switch Medium Tapped to Collector Box & Low pressure switch High Tapped to Low pressure switch Set points are progressive higher Low to High UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Modulating Furnace Pressure Switches Modulating Furnace uses 3 pressure switches Low Tapped to Medium & High pressure switch Medium Tapped to Collector Box & High pressure switch High Tapped to Low pressure switch Set points are progressive higher Low to High UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Modulating Furnace Wiring Diagram UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Modulating Furnace Wiring Diagram UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Modulating Furnace Pressure Switch Labels UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
Modulating Furnace Pressure Switches Low High Medium To Collector Box Switches are linked so one reference hose pulls on the diaphragm of each switch UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
A-90 Pressure Switch Settings Single and Two Stage Pressure Switches Part Number Collector Box Pressure Switch Housing Pressure Switch Max Make-IWC Nom Break-IWC 1184413 0.83 0.68 +/- 0.05 0.49 0.34 +/- 0.05 1184414 0.90 0.75 +/- 0.05 0.45 0.30 +/- 0.05 1184415 0.93 0.78 +/- 0.05 1184951 0.93 0.56 0.41 +/- 0.05 UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
A-90 Pressure Switch Settings Modulating Pressure Switch Settings Maximum Heat Pressure Switch Intermediate Heat Pressure Switch Minimum Heat Pressure Switch Input Max Make-IWC Nom Break-IWC Nom Break- IWC 60,000 17” casing 1.21 1.05 +/- 0.06 0.85 0.70 +/- 0.05 0.62 0.47 +/-0.05 21” casing 1.46 1.29 +/- 0.07 1.00 0.85 +/- 0.05 0.64 0.49 +/- 0.05 80,000 1.58 1.40 +/- 0.08 0.75 0.60 +/-0.05 100,000 1.08 0.93 +/- 0.05 0.87 0.72 +/- 0.50 120,000 1.05 0.90 +/- 0.05 0.80 0.65 +/-0.05 UTC Climate | Controls | Security Proprietary and Confidential Information Not for Further Distribution
A little demo time