Grundfos JP User Manual

Remedy
Repair or replace the pressure manager.
Find more information in the service instructions
at https://product-selection.grundfos.com.
8.4.5 The "Pump on" indicator light is on, but the
pump does not start
Cause
The power supply to the pump is disconnected.
Remedy
Check the plug and cable connections, and make
sure that the built-in circuit breaker of the pump is
switched off.
Cause
The motor protection of the pump has tripped due to
overload.
Remedy
Make sure the motor or pump is not blocked.
Cause
The pump is defective.
Remedy
Repair or replace the pump.
Cause
The pressure manager is defective.
Remedy
Repair or replace the pressure manager.
Find more information in the service instructions
at https://product-selection.grundfos.com
8.4.6
The pump does not start when water is
consumed
The "Pump on" indicator light is off.
Cause
There is too big a difference in height between the
pressure manager and the tapping point.
Remedy
Adjust the installation, or increase the start
pressure.
Cause
The pressure manager is defective.
Remedy
Repair or replace the pressure manager.
Find more information in the service instructions
at https://product-selection.grundfos.com.
8.4.7
The pump does not stop
Cause
The pump cannot deliver the necessary outlet
pressure.
Remedy
Replace the pump.
Cause
The start pressure is set too high.
Remedy
• PM 1: The start pressure is factory set. Make
sure that your product is dimensioned
correctly.
• PM 2, PM TWIN: Decrease the start pressure.
Cause
The non-return valve is stuck in open position.
Remedy
Clean or replace the non-return valve.
Cause
The pressure manager is defective.
Remedy
Repair or replace the pressure manager.
Find more information in the service instructions
at https://product-selection.grundfos.com.
8.5 Fault finding boosters with a pressure
tank
8.5.1 The booster starts and stops too frequently
Cause
Incorrect precharge pressure.
Remedy
Adjust the diaphragm tank pressure.
Cause
Leakage in pipes.
Remedy
Check and repair the pipes.
Cause
The diaphragm is broken. Water escapes if the air
valve is pushed down.
Remedy
Replace the pressure tank.
8.6 Fault finding the pressure switch
8.6.1
The motor does not start
Cause
Problem with the pressure switch
Remedy
• Check that the pressure switch is live. Verify
power at the switch terminals.
21
English (GB)

Grundfos JP Specifications

General

Power supply	Electric
Material	Stainless Steel, Cast Iron
Applications	pressure boosting
Pump Type	Self-priming centrifugal pump
Horsepower	1.5 HP
Phase	Single-phase
Inlet Size	1 inch
Outlet Size	1 inch