EWC Controls ST-3-E Control Panel
The EWC Controls ST-3-E Control Panel is a rugged, relay-based 3-zone control system engineered for single-stage heating and cooling applications utilizing manual changeover. As the direct replacement for ST-2-E, this 24VAC zone controller is field-proven for reliability in gas, electric, and hydro-air systems. The "E" revision introduces an integrated thermal polyfuse, eliminating the need for traditional 3-amp glass fuses and providing self-resetting over-current protection against field wiring shorts. Zone 1 acts as the master interface, requiring a thermostat with "O" and "B" terminals to dictate the system mode. Slave zones (2 and 3) operate efficiently with standard non-power stealing thermostats, providing a cost-effective solution for multi-zone residential or light commercial ductwork. The ULTRA-ZONE ST-3-E supports both 2-wire and 3-wire motorized dampers and can be "twinned" with a second panel to expand capacity up to 6 zones for more complex floor plans.
Key Benefits:- Direct Retrofit Compatibility: Perfectly replaces legacy ST-2-E and ST-3 models with zero modifications to existing 24V wiring.
- Enhanced System Protection: Features an onboard thermal polyfuse that protects the logic board from thermostat or damper shorts.
- Flexible Damper Control: Compatible with EWC URD, ND, RSD, and SID series, or any standard 24VAC power-open/power-close dampers.
- Adjustable Airflow Logic: Onboard switches allow technicians to set default damper positions (open or closed) during system idle periods.
- Expandable Architecture: Master/slave circuitry allows for easy interconnection of two panels to manage up to 6 independent zones.
Is the ST-3-E compatible with heat pump systems?
No, this panel is designed specifically for 1-stage heat / 1-stage cool conventional systems. It utilizes master/slave logic via "O" and "B" terminals for manual changeover and cannot control heat pump reversing valves.
What thermostats should be used with this panel?
The master zone requires a thermostat with dedicated "O" and "B" terminals. All zones should use mechanical or digital non-power stealing thermostats; high-draw Wi-Fi thermostats are generally not recommended without an isolation relay.
How do I reset the board if it stops responding?
If the thermal circuit breaker trips due to a short, remove the 24VAC power source for approximately 30 seconds to allow the polyfuse to cool and reset.
This item is not eligible for free shipping.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
EWC Controls ST-3-E Control Panel
The EWC Controls ST-3-E Control Panel is a rugged, relay-based 3-zone control system engineered for single-stage heating and cooling applications utilizing manual changeover. As the direct replacement for ST-2-E, this 24VAC zone controller is field-proven for reliability in gas, electric, and hydro-air systems. The "E" revision introduces an integrated thermal polyfuse, eliminating the need for traditional 3-amp glass fuses and providing self-resetting over-current protection against field wiring shorts. Zone 1 acts as the master interface, requiring a thermostat with "O" and "B" terminals to dictate the system mode. Slave zones (2 and 3) operate efficiently with standard non-power stealing thermostats, providing a cost-effective solution for multi-zone residential or light commercial ductwork. The ULTRA-ZONE ST-3-E supports both 2-wire and 3-wire motorized dampers and can be "twinned" with a second panel to expand capacity up to 6 zones for more complex floor plans.
Key Benefits:- Direct Retrofit Compatibility: Perfectly replaces legacy ST-2-E and ST-3 models with zero modifications to existing 24V wiring.
- Enhanced System Protection: Features an onboard thermal polyfuse that protects the logic board from thermostat or damper shorts.
- Flexible Damper Control: Compatible with EWC URD, ND, RSD, and SID series, or any standard 24VAC power-open/power-close dampers.
- Adjustable Airflow Logic: Onboard switches allow technicians to set default damper positions (open or closed) during system idle periods.
- Expandable Architecture: Master/slave circuitry allows for easy interconnection of two panels to manage up to 6 independent zones.
Is the ST-3-E compatible with heat pump systems?
No, this panel is designed specifically for 1-stage heat / 1-stage cool conventional systems. It utilizes master/slave logic via "O" and "B" terminals for manual changeover and cannot control heat pump reversing valves.
What thermostats should be used with this panel?
The master zone requires a thermostat with dedicated "O" and "B" terminals. All zones should use mechanical or digital non-power stealing thermostats; high-draw Wi-Fi thermostats are generally not recommended without an isolation relay.
How do I reset the board if it stops responding?
If the thermal circuit breaker trips due to a short, remove the 24VAC power source for approximately 30 seconds to allow the polyfuse to cool and reset.
This item is not eligible for free shipping.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
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Description
The EWC Controls ST-3-E Control Panel is a rugged, relay-based 3-zone control system engineered for single-stage heating and cooling applications utilizing manual changeover. As the direct replacement for ST-2-E, this 24VAC zone controller is field-proven for reliability in gas, electric, and hydro-air systems. The "E" revision introduces an integrated thermal polyfuse, eliminating the need for traditional 3-amp glass fuses and providing self-resetting over-current protection against field wiring shorts. Zone 1 acts as the master interface, requiring a thermostat with "O" and "B" terminals to dictate the system mode. Slave zones (2 and 3) operate efficiently with standard non-power stealing thermostats, providing a cost-effective solution for multi-zone residential or light commercial ductwork. The ULTRA-ZONE ST-3-E supports both 2-wire and 3-wire motorized dampers and can be "twinned" with a second panel to expand capacity up to 6 zones for more complex floor plans.
Key Benefits:- Direct Retrofit Compatibility: Perfectly replaces legacy ST-2-E and ST-3 models with zero modifications to existing 24V wiring.
- Enhanced System Protection: Features an onboard thermal polyfuse that protects the logic board from thermostat or damper shorts.
- Flexible Damper Control: Compatible with EWC URD, ND, RSD, and SID series, or any standard 24VAC power-open/power-close dampers.
- Adjustable Airflow Logic: Onboard switches allow technicians to set default damper positions (open or closed) during system idle periods.
- Expandable Architecture: Master/slave circuitry allows for easy interconnection of two panels to manage up to 6 independent zones.
Is the ST-3-E compatible with heat pump systems?
No, this panel is designed specifically for 1-stage heat / 1-stage cool conventional systems. It utilizes master/slave logic via "O" and "B" terminals for manual changeover and cannot control heat pump reversing valves.
What thermostats should be used with this panel?
The master zone requires a thermostat with dedicated "O" and "B" terminals. All zones should use mechanical or digital non-power stealing thermostats; high-draw Wi-Fi thermostats are generally not recommended without an isolation relay.
How do I reset the board if it stops responding?
If the thermal circuit breaker trips due to a short, remove the 24VAC power source for approximately 30 seconds to allow the polyfuse to cool and reset.
This item is not eligible for free shipping.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
