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3/4 In Lead Free Boiler Pressure Relief Valve, 100 psi, Threaded Female Connections
LF174A-100 3/4 - spec sheet
LF174A-100 3/4 - spec sheet
Manufacturer Resources
Product Specs
- Buy American Act Compliant:
- USA
- Department:
- Plumbing
- Product Group:
- Plumbing
- Product Subgroup:
- Valves
- Product Type:
- Relief Valve
Watts LF174A-100 3/4 – Frequently Asked Questions
1) What pressure does the Watts LF174A-100 3/4 relief valve open at?
The LF174A-100 3/4 is set at 100 psi. It is a boiler pressure relief valve, so it protects a hot water heating boiler by discharging when system pressure reaches that setting. If your boiler nameplate lists a maximum allowable working pressure below 100 psi, this is the wrong setting and you need a valve set at or below that rating.
2) What size and type of connections does the Watts LF174A boiler relief valve have?
It is a 3/4 inch valve with threaded female connections, so it threads onto 3/4 inch male NPT nipples on both the boiler tapping and the discharge side. No union or sweat adapter is included, so plan on a nipple at the boiler and a nipple plus elbow to run the discharge line down toward the floor.
3) Is the Watts LF174A-100 lead free and can I use it on potable water heating systems?
Yes, the LF174A-100 3/4 is a lead free boiler pressure relief valve, which is what codes require on plumbing that serves potable water. Note it is a boiler relief valve, not a combination temperature and pressure (T&P) valve, so it is not the part for a domestic water heater tank.
4) Is the Watts LF174A-100 3/4 valve Buy American compliant for a government or institutional job?
Yes. The LF174A-100 3/4 is flagged Buy American Act compliant with USA origin, which is what a federal, school district, or municipal procurement spec usually calls for on boiler room trim.
5) What part number do I order for a 3/4 inch 100 psi Watts lead free boiler relief valve?
Order Watts LF174A-100 3/4. That is the manufacturer part number, and it identifies the 3/4 inch lead free version of the 174A boiler relief valve set at 100 psi with female threaded ends. The LF prefix is the lead free construction and the number after the dash is the set pressure.
6) Can I use this Watts relief valve as the safety valve on a steam boiler?
No. The LF174A-100 3/4 is a boiler pressure relief valve for hot water heating systems, set at 100 psi. Steam boilers require a steam safety valve sized and set for steam service, typically at 15 psi on a low pressure system. Do not substitute this valve for one.
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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 LF174A-100 3/4 come with a warranty?
Absolutely. The Watts LF174A-100 3/4 is backed by a manufacturer’s warranty.
For full warranty terms, check the product documentation or Contact Us.
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