SUPCO SLP0520 Pressure Switch – Automatic Reset, High/Low & Condenser Fan Cycling
The SUPCO SLP0520 Pressure Switch is a high-precision, automatic-reset switch designed for refrigeration, air conditioning, and heat pump systems. It offers high reliability, excellent repeatability, and compact design for direct mounting, making it ideal for controlling system pressure and fan operation in commercial and residential HVAC/R applications.
✅ Key Features
✅ High Pressure SPST – opens on pressure rise
✅ Low Pressure SPST – opens on pressure fall
✅ Condenser Fan Cycling SPST – opens on pressure rise
✅ 1/4” female SAE connection – standard for easy installation
✅ Snap-acting stainless steel hermetically sealed sensor – ensures accurate and reliable operation
✅ Compact and lightweight – allows direct mounting in tight spaces
✅ Excellent set point repeatability and stability – maintains system efficiency
✅ Pressure Range: 0 to 650 PSI
✅ Burst Pressure: 5000 PSI
✅ Rated Life: 100,000 cycles at rated load
✅ Voltage Ratings: 24 / 120 / 240V, 50/60 Hz (6 RLA, 36 LRA)
✅ Operating Temperature: Ambient 20°F to 176°F (-30°C to 80°C); Fluid 60°F to 250°F (-50°C to 120°C)
📊 Specifications / Competitive Comparison – Low Pressure
| Feature | Specification |
|---|
| Part Number |
SLP0520 |
| Open PSI |
5 PSI |
| Close PSI |
20 PSI |
| Tolerance |
±5 PSI |
| Klixon Equivalent |
PS80-K2-F0305-020-005 |
| Mars Equivalent |
33329 |
| A-1 Equivalent |
PS-LP05-20 |
| Ranco Equivalent |
MPL-7001 |
| Robertshaw Equivalent |
3101-001 |
| Tecumseh Equivalent |
N/A |
| Johnson Controls Equivalent |
P100AC-1C |
⚠️ Common Symptoms of a Faulty Pressure Switch
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HVAC or refrigeration system fails to start
-
Compressor cycles on/off erratically
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Condenser fan does not activate at correct pressure
-
System trips high/low pressure alarms without apparent cause
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Visible signs of wear, corrosion, or fluid leakage around the switch
Replacing a faulty pressure switch restores system safety, efficiency, and reliable operation.
❓ Frequently Asked Questions (FAQ)
Q: What applications is the SLP0520 designed for?
A: Refrigeration systems, air conditioning systems, and heat pump systems.
Q: What does SPST mean?
A: SPST stands for Single Pole, Single Throw, meaning the switch opens or closes a single electrical circuit.
Q: What is the pressure range of the SLP0520?
A: It operates between 0 and 650 PSI, with a burst pressure of 5000 PSI.
Q: Is it easy to install?
A: Yes, the 1/4” female SAE connection and compact design allow direct mounting in most HVAC/R systems.
Q: How long will the switch last?
A: Rated for 100,000 cycles at the rated electrical load.
🛒 Shopping Tips
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✅ Verify your system’s pressure requirements before ordering
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✅ Check electrical rating (24 / 120 / 240V, 50/60 Hz)
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✅ Inspect the connection type to ensure compatibility (1/4” SAE female)
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✅ Always replace a faulty or worn pressure switch to maintain safety and efficiency
