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Manufacturer Resources
Product Specs
- Application:
- Boiler
- Body Material:
- Bronze
- Country Of Origin:
- United States
- Inlet Connection Size:
- 3/4 IN
- Inlet Connection Type:
- Female Threaded
- Inlet Thread Type:
- NPT
- Maximum Temperature:
- 250°F
- Maximum Working Pressure:
- 30
- Outlet Connection Size:
- 3/4 IN
- Outlet Connection Type:
- Female Threaded
- Outlet Thread Type:
- NPT
- Pressure Range:
- 30 to 150 PSI
- Pressure Relief Setting:
- 40 PSI
- Pressure Steam Discharge Capacity:
- 800,000 BTU per hour
- Protection Type:
- Pressure
- Series:
- 174A
- Test Lever:
- Yes
- Department:
- Plumbing
- Product Group:
- Plumbing
- Product Subgroup:
- Valves
- Product Type:
- Relief Valve
Watts 274479 – Frequently Asked Questions
1) Will the Watts 0274479 thread straight into a 3/4 inch tapping on my boiler?
Yes, if the tapping is 3/4 inch NPT male. Both the inlet and the outlet on the 0274479 are 3/4 inch female NPT, so it screws onto a 3/4 inch male nipple off the boiler and takes a 3/4 inch male-threaded discharge pipe on the outlet. No adapters or unions come with it.
2) Is this Watts relief valve big enough for my boiler's BTU input?
The 0274479 has a steam discharge capacity of 800,000 BTU per hour. Size by the boiler's gross output rating on the nameplate: as long as that number is at or below 800,000 BTU/hr, this valve relieves the full output. A larger boiler needs a higher-capacity valve.
3) Does this Watts boiler relief valve have a test lever for annual maintenance?
Yes, the 0274479 comes with a manual test lever, so maintenance staff can lift and flush the seat on the routine check without breaking any piping. That matters on multi-family and institutional boiler rooms where the relief valve gets exercised on a schedule.
4) Do I need a shutoff valve or reducer between the boiler and this relief valve?
No shutoff of any kind goes between the boiler and the relief valve, and nothing may reduce the 3/4 inch line. Pipe the 0274479 directly off a full-size 3/4 inch tapping, then run the discharge full size in 3/4 inch down to within a few inches of the floor, terminating open so it can't be plugged or capped.
5) What relief settings does the Watts 174A series cover if 40 psi isn't what my boiler calls for?
The 174A family spans settings from 30 to 150 psi, and model 0274479 is the 40 psi version. Match the valve's set pressure to the maximum allowable working pressure stamped on your boiler, never above it.
6) What temperature can the Watts 174A relief valve handle?
250 degrees F maximum. That covers normal hot water heating boiler operation. The body is bronze, which holds up to continuous hot water and the mineral content typical of make-up water better than a plated steel body would.
7) Is the Watts 0274479 made in the USA?
Yes. Country of origin on the 174A 0274479 bronze relief valve is the United States, which matters for public and institutional jobs carrying domestic-content procurement language.
How fast can I get the Watts 274479 delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the
continental
U.S.
Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit,
reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Watts 274479 come with a warranty?
Absolutely. The Watts 274479 is backed by a manufacturer’s warranty.
For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Watts 274479?
You can call, text, or email our expert support team for fast answers. We’re here to help with
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selection,
installation tips, and troubleshooting. Contact Us
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