RO Low Pressure Switch (LPS)

Inclusive of 18% GST • Free standard delivery on orders above ₹499

Role in the Purification Chain

The safety sensor guarding your booster pump. If your overhead water tank runs dry or municipal tap pressure drops to zero, the LPS cuts off electrical power immediately, preventing the booster pump from running dry, overheating, and burning its motor.

Physical & Mechanical Principle

A pressure-sensitive diaphragm held against an internal micro-switch. When feed water pressure exceeds 4 PSI, the diaphragm flexes and closes the electrical contact, allowing the machine to start. When water cuts out, it opens the circuit instantly.

The 'Dead Pump' Diagnosis When Tap Pressure Is Just Low

When a purifier refuses to turn on, technicians often falsely diagnose a burned booster pump. In reality, the pump is in perfect health; the LPS simply disconnected power because the overhead tank water level is slightly low.

Temporarily bridge the two LPS wires with a paperclip or jumper. If the pump immediately turns on, the pump is 100% fine. The issue is simply low water pressure or a faulty ₹59 switch.

Locate LPS

Find the small pressure switch on the raw water inlet tube before the pump.

Test with Jumper

Disconnect two electrical terminals and touch them together briefly. If machine starts, LPS is the culprit.

Swap 1/4" Tubes

Push collar ring and transfer inlet pipe to the new LPS switch.

Reconnect Terminals

Plug the two spade terminals onto the new switch.

How to Bypass and Test a Low Pressure Switch (LPS) in 2 Minutes

Diagnose why your purifier won't turn on without paying for an unnecessary pump replacement.

Can I run my purifier with LPS bypassed permanently?

Not recommended. Bypassing permanently means if your water supply runs dry, your booster pump will run dry, overheat, and burn out its motor.