Tjernlund Products PS1503 Switch
The Tjernlund Products PS1503 is a high-sensitivity duct pressure switch engineered to automate HVAC accessories by detecting positive air pressure within the supply plenum or trunk lines. As the direct replacement for DFS-221-227, this SPST normally open switch simplifies field installations by eliminating the need for complex interlock wiring with the furnace blower. The PS1503 duct airstat features a snap-acting mechanism triggered by a precise pressure rise of +0.05 +/- 0.02" W.C., ensuring consistent activation of auxiliary equipment such as duct booster fans, humidifiers, and UV air purifiers. Housed in a durable enclosure with an integral sampling tube, this positive pressure switch supports electrical ratings up to 15 Amps non-inductive at 277 VAC or 300 VA pilot duty. Field technicians must ensure the diaphragm is mounted vertically to maintain set-point accuracy and prevent gravity-induced switching errors, providing a reliable control solution for high-performance airflow management systems.
Key Benefits- Universal Compatibility: Serves as a drop-in replacement for DFS-221-227 pressure switches.
- Precision Sensing: Actuates at a low-threshold positive pressure rise for sensitive air detection.
- High Electrical Capacity: Rated for 15 Amps non-inductive and 300 VA pilot duty circuits.
- Flexible Application: Ideal for triggering electronic air cleaners, humidifiers, and in-line booster fans.
- Simplified Integration: Eliminates the requirement to find a 24V or 120V tap on the blower motor.
Can I install the PS1503 on the return air side?
No, the PS1503 is specifically designed to sense positive pressure. For return air applications where negative pressure is present, a vacuum-sensing or differential pressure switch is required.
Why is the mounting orientation critical for this airstat?
The internal diaphragm is calibrated for vertical mounting. Installing the switch horizontally can result in shifting the set-point or failing to reset properly due to the physical weight of the diaphragm mechanism.
Does this switch require a separate power source?
The PS1503 is a non-adjustable mechanical switch that acts as a dry contact. It breaks or makes the "hot" leg of the circuit assigned to the accessory it is controlling, adhering to local HVAC electrical code requirements.
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.
Original: $81.46
-65%$81.46
$28.51Tjernlund Products PS1503 Switch
The Tjernlund Products PS1503 is a high-sensitivity duct pressure switch engineered to automate HVAC accessories by detecting positive air pressure within the supply plenum or trunk lines. As the direct replacement for DFS-221-227, this SPST normally open switch simplifies field installations by eliminating the need for complex interlock wiring with the furnace blower. The PS1503 duct airstat features a snap-acting mechanism triggered by a precise pressure rise of +0.05 +/- 0.02" W.C., ensuring consistent activation of auxiliary equipment such as duct booster fans, humidifiers, and UV air purifiers. Housed in a durable enclosure with an integral sampling tube, this positive pressure switch supports electrical ratings up to 15 Amps non-inductive at 277 VAC or 300 VA pilot duty. Field technicians must ensure the diaphragm is mounted vertically to maintain set-point accuracy and prevent gravity-induced switching errors, providing a reliable control solution for high-performance airflow management systems.
Key Benefits- Universal Compatibility: Serves as a drop-in replacement for DFS-221-227 pressure switches.
- Precision Sensing: Actuates at a low-threshold positive pressure rise for sensitive air detection.
- High Electrical Capacity: Rated for 15 Amps non-inductive and 300 VA pilot duty circuits.
- Flexible Application: Ideal for triggering electronic air cleaners, humidifiers, and in-line booster fans.
- Simplified Integration: Eliminates the requirement to find a 24V or 120V tap on the blower motor.
Can I install the PS1503 on the return air side?
No, the PS1503 is specifically designed to sense positive pressure. For return air applications where negative pressure is present, a vacuum-sensing or differential pressure switch is required.
Why is the mounting orientation critical for this airstat?
The internal diaphragm is calibrated for vertical mounting. Installing the switch horizontally can result in shifting the set-point or failing to reset properly due to the physical weight of the diaphragm mechanism.
Does this switch require a separate power source?
The PS1503 is a non-adjustable mechanical switch that acts as a dry contact. It breaks or makes the "hot" leg of the circuit assigned to the accessory it is controlling, adhering to local HVAC electrical code requirements.
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 Tjernlund Products PS1503 is a high-sensitivity duct pressure switch engineered to automate HVAC accessories by detecting positive air pressure within the supply plenum or trunk lines. As the direct replacement for DFS-221-227, this SPST normally open switch simplifies field installations by eliminating the need for complex interlock wiring with the furnace blower. The PS1503 duct airstat features a snap-acting mechanism triggered by a precise pressure rise of +0.05 +/- 0.02" W.C., ensuring consistent activation of auxiliary equipment such as duct booster fans, humidifiers, and UV air purifiers. Housed in a durable enclosure with an integral sampling tube, this positive pressure switch supports electrical ratings up to 15 Amps non-inductive at 277 VAC or 300 VA pilot duty. Field technicians must ensure the diaphragm is mounted vertically to maintain set-point accuracy and prevent gravity-induced switching errors, providing a reliable control solution for high-performance airflow management systems.
Key Benefits- Universal Compatibility: Serves as a drop-in replacement for DFS-221-227 pressure switches.
- Precision Sensing: Actuates at a low-threshold positive pressure rise for sensitive air detection.
- High Electrical Capacity: Rated for 15 Amps non-inductive and 300 VA pilot duty circuits.
- Flexible Application: Ideal for triggering electronic air cleaners, humidifiers, and in-line booster fans.
- Simplified Integration: Eliminates the requirement to find a 24V or 120V tap on the blower motor.
Can I install the PS1503 on the return air side?
No, the PS1503 is specifically designed to sense positive pressure. For return air applications where negative pressure is present, a vacuum-sensing or differential pressure switch is required.
Why is the mounting orientation critical for this airstat?
The internal diaphragm is calibrated for vertical mounting. Installing the switch horizontally can result in shifting the set-point or failing to reset properly due to the physical weight of the diaphragm mechanism.
Does this switch require a separate power source?
The PS1503 is a non-adjustable mechanical switch that acts as a dry contact. It breaks or makes the "hot" leg of the circuit assigned to the accessory it is controlling, adhering to local HVAC electrical code requirements.
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.
