Totaline PA37 & PS021-0004L Low Pressure Switch
Compact fixed-setting low pressure switches for air-conditioning and refrigeration systems, designed to monitor suction-side pressure and provide reliable pressure-responsive switching for compatible HVACR equipment.
PA37 PS021-0004L Low Pressure Fixed Setting R22 R410A❄️ Totaline Low Pressure Switch
The Totaline PA37 and PS021-0004L Low Pressure Switches are compact pressure controls for compatible air-conditioning and refrigeration applications.
A low pressure switch is normally connected to the low-pressure / suction side of a refrigeration circuit. It monitors suction pressure and changes its electrical contact state when pressure falls to its predetermined OFF pressure.
When system pressure rises again to the specified ON pressure, the switch returns to its corresponding operating state, allowing it to form part of a properly designed compressor or equipment control circuit.
The Totaline design combines a compact pressure switch, factory-set switching points and pre-wired cable in a straightforward replacement component for compatible HVACR equipment.
📋 Available Models
Totaline PA37
ON 60 PSI / OFF 30 PSI Low Pressure R22 Fixed SettingFixed-setting low pressure switch for compatible R22 air-conditioning and refrigeration systems.
ON: 60 PSI ≈ 4.14 bar
OFF: 30 PSI ≈ 2.07 bar
Cable Length: 1500 mm
Totaline PS021-0004L
ON 115 PSI / OFF 65 PSI Low Pressure R410A Fixed SettingFixed-setting low pressure switch designed for compatible R410A air-conditioning and refrigeration systems.
ON: 115 PSI ≈ 7.93 bar
OFF: 65 PSI ≈ 4.48 bar
Cable Length: 1000 mm
🔄 How a Low Pressure Switch Works
The switch monitors pressure on the low-pressure side of the refrigeration circuit.
Suction pressure decreases according to the system operating condition.
When pressure reaches the fixed OFF value, the electrical contact changes state.
The equipment control circuit responds to the low-pressure switch signal.
Low-side pressure rises again when system conditions recover.
At the specified ON pressure, the switch returns to its corresponding operating state.
🛡️ Why Low Pressure Control Is Important
Low suction pressure can occur for several reasons in an air-conditioning or refrigeration system. A low-pressure switch provides a pressure-responsive electrical signal that can be incorporated into the equipment's control and protection strategy.
💰 Why Choose Totaline Low Pressure Switch?
For equipment requiring these specific fixed pressure settings, Totaline PA37 and PS021-0004L provide a practical HVACR replacement solution backed by the Totaline parts brand.
🏭 Typical Applications
🔧 How to Select the Correct Model
| Selection Point | PA37 | PS021-0004L |
|---|---|---|
| Pressure Function | Low Pressure | Low Pressure |
| ON Pressure | 60 PSI | 115 PSI |
| OFF Pressure | 30 PSI | 65 PSI |
| Listed Refrigerant | R22 | R410A |
| Cable Length | 1500 mm | 1000 mm |
| Selection | Always match the original equipment pressure setting, refrigerant, pressure connection and electrical requirements. | |
📌 Understanding ON & OFF Pressure
PS021-0004L: 115 PSI ON ← Pressure Recovers | Pressure Falls → 65 PSI OFF
Totaline Low Pressure Switch Supplier Malaysia
RNA Engineering & Trading Sdn Bhd supplies Totaline pressure switches and HVACR spare parts for air-conditioning, commercial refrigeration and cooling-system applications.
Contact our team for pricing, availability, replacement matching and product selection.
Inquiry - Totaline Low Pressure Switch