Flojet 02090-103 Pressure Switch Kit, 32-45 PSI
The Flojet 02090-103 is the genuine pressure switch kit with a 32-45 PSI operating band, supplied in the unthreaded configuration. The two figures are the switch’s cut-in and cut-out points: the pump starts when line pressure falls to about 32 PSI and stops again once it has built to about 45.
That gap between the two numbers is called the differential, and it is doing something important. If a switch turned the pump off and on at the same pressure it would chatter constantly, hammering its own contacts and the pump with it. The differential gives the system somewhere to sit — open a tap and the pressure has to fall a useful amount before the pump bothers to start, and once it does start it runs long enough to do meaningful work rather than blipping on and off.
A 32-45 PSI band is the comfortable middle of the range for general fresh water service: enough pressure at the outlets for a decent shower and a properly working tap, without the strain on plumbing and fittings that a high-pressure system imposes. The unthreaded version mounts to the pump without a threaded port connection, so check which mounting arrangement your pump uses before ordering.
Key Features
- Genuine Flojet (Xylem) service part — correct switch and mounting for the pump
- 32-45 PSI cut-in and cut-out band for general fresh water service
- Sensible differential that prevents the contact-hammering chatter of a narrow band
- Unthreaded configuration — check which mounting your pump uses
- Supplied as a kit rather than as separate components
Applications
- Flojet demand water systems specifying a 32-45 PSI switch
- General fresh water service with taps and a shower
- Replacing a switch that has lost calibration or cycles rapidly
- Systems where high pressure would strain older plumbing
- Marine, RV and mobile pressurised water systems
Specifications
- Brand: Flojet (Xylem)
- Manufacturer Part Number: 02090-103
- Part Type: Pressure switch kit
- Cut-In Pressure: Approximately 32 PSI
- Cut-Out Pressure: Approximately 45 PSI
- Configuration: Unthreaded
- Condition: New
Frequently Asked Questions
Q: What does the differential between the two pressures do?
It stops the switch chattering. Without a gap between cut-in and cut-out, the pump would start and stop continuously around a single pressure, destroying the contacts and the pump.
Q: Is a wider differential better?
Not necessarily. A wide band means fewer starts but a more noticeable change in flow at the tap as pressure falls; a narrow one gives steadier pressure but more cycling. The factory setting is the balance the pump was designed around.
Q: What is the difference between the threaded and unthreaded versions?
How the switch connects to the pump body. They are not interchangeable, so identify which your pump takes before ordering rather than after.
Q: Does altitude or temperature affect the settings?
Marginally. Neither is worth compensating for in a domestic-scale water system; if the pressures have genuinely drifted, the switch itself has aged rather than the conditions.
Not sure this is the right part? Send us a Picture of the pump plate on your pump and the CLR Marine team will confirm the correct part before you order.
CLRMarine
