Watts ST500 Float Valve 1/2 In Bronze Pipe Mount Bathware
Bronze float valve for horizontal pipe mounting with 20 gpm flow at 50 psi and 31 gpm at 100 psi
- Size1/2 in
- Delivers 20 gpm flow at 50 psi for efficient tank filling
- Provides 31 gpm flow at 100 psi to handle higher demand
- Withstands up to 125 psi maximum pressure for durable service
- Operates reliably up to 180 °F maximum temperature for hot water use
- Bronze body and brass rod resist corrosion for long service life
Watts ST500 Float Valve 1/2 In Bronze
The Watts ST500 is a bronze float valve with a 1/2 inch MNPT connection for horizontal pipe mounting. It controls water flow in tanks or cisterns using a brass rod with 1/4-20 threading. The valve body is bronze and rated for a maximum pressure of 125 psi and a maximum temperature of 180 Degrees F. It suits residential and light commercial plumbing installations.
Installing the 1/2 In MNPT Valve
Thread the valve onto the horizontal supply pipe using the 1/2 inch MNPT connection and secure the brass rod to the float mechanism. Apply thread sealant to the male threads to prevent leaks at the joint. Ensure the rod moves freely without binding against the tank wall or other fittings. Overtightening the bronze body can crack the casting or strip the threads.
Check Your Tank and Supply Before Ordering
Verify the supply line uses a 1/2 inch female NPT thread to match the valve inlet. Confirm the system operating pressure does not exceed 125 psi and water temperature stays below 180 Degrees F. The valve delivers 20 gpm at 50 psi and 31 gpm at 100 psi, so ensure the flow capacity meets the tank refill requirement. California Proposition 65 warnings apply for cancer and reproductive harm.
How it compares
Measured against everything we stock in Bath Accessories & Soap Dispensers, at today’s prices. Recalculated every night.
- Price $43.99
- Typical for this category: the median of 1,499 items is $39.99.
Specifications
| Product | |
|---|---|
| Brand name | WATTS |
| Product type | Other |
| Size & build | |
| Size | 1/2 in |
Questions about this item
How do I verify the float valve is operating correctly once installed?
Check that water flow stops when the float reaches its set level and confirm the supply pressure stays within the 50 psi to 125 psi range marked on the body.
What comes in the box and what must I supply myself?
The valve body with 1/2 in MNPT threaded outlet and brass rod with 1/4 in -20 threads are included; you will need to provide the float and any pipe fittings.
Which pressure rating should I select for my system?
The valve delivers 20 gpm at 50 psi and 31 gpm at 100 psi, so choose based on your normal supply pressure up to the 125 psi maximum.
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