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$56.65 each
In Stock
Get 40 Tomorrow, Jun 18
Order by 6PM, receive Tomorrow
This item replaces: 0342671
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Product Highlights
–
3/4"
30 psi
510000 BTU Capacity
Description
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Watts 0342692 M335M2 3/4" Male Pressure Relief Valve is a bronze boiler pressure relief valve used on low pressure hot water and steam heating boilers to provide automatic overpressure protection at a 30 psi set point.
Key Features:
Compatibility & Applications:
Installation & Operation Notes:
Maintenance & Troubleshooting:
Key Features:
- OEM Watts 335 series safety relief valve for hydronic and steam heating equipment
- 3/4" male NPT inlet with 3/4" female NPT outlet for direct connection at the boiler tapping and relief line
- Factory set relief pressure of 30 psi for typical residential and light commercial boiler applications
- Bronze body construction with stainless steel spring and guided stem for consistent operation
- Nonstick seating surfaces designed to promote reliable reseating after lift events
- Rated discharge capacity suitable for boilers up to 510,000 BTU when applied per Watts sizing information
Compatibility & Applications:
- Intended for use on residential and light commercial hot water or low pressure steam boilers where a 30 psi relief valve is specified
- Compatible with boiler outlets that accept a 3/4" male NPT relief valve connection
- Used in hydronic systems that require an ASME safety relief valve sized to the boiler input or output rating
- Appropriate for new boiler installations and replacement of older Watts 335 series valves where model M335M2 is specified as the current equivalent
Installation & Operation Notes:
- Install the valve in a vertical position at the boiler relief tapping, following boiler and Watts instructions
- Pipe the discharge outlet to a safe, visible termination point with appropriately sized tubing or pipe and minimal restrictions
- Do not install any shutoff valve between the boiler and the relief valve or in the relief discharge line
- After installation, verify that the system is filled, purged, and operating within design pressure limits while the valve remains closed
- Test operation and inspect for leaks according to local codes and maintenance practices
Maintenance & Troubleshooting:
- Inspect the relief valve periodically for corrosion, leakage at the seat, or signs of discharge on the outlet piping
- Replace the valve if leakage persists at normal operating pressure, if corrosion is present, or if there is any sign of mechanical damage
- If nuisance lifting occurs, verify system operating pressure, expansion tank sizing, and control settings before replacing the valve
- Do not attempt to repair or modify internal parts; relief valves are typically replaced rather than rebuilt in field service
Specs
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| Size: | 3/4" |
|---|---|
| Pressure Set Point: | 30 psi |
| Capacity (BTU): | 510000 |
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Product Reviews
4.75 out of 96 reviews
96% would recommend this product
5 star
88%
4 star
7%
3 star
1%
2 star
1%
1 star
3%
Customer Images
Most Liked Positive Review
New Pressure Relief Valve Arrives Quickly
The 4 year old boiler pressure relief valve (Watts 3/4" M330-M1 30psi 375000 BTU/hr rating) was leaking a little water when the boiler system was at low temperature and normal pressure of about 16 to 18 pounds. This Watts M335-M2, 3/4" Male Pressure Relief Valve, 30psi, 510000 BTU/hr rating, was used to replace the old leaking valve. This new valve stopped the boiler water leak out of the pressure relief valve.
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Most Liked Negative Review
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Didn't Last
I purchased this relief valve for my boiler back in late 2013 and it worked for just under 29 months. Now it releases pressure at under 10 psi and caused my boiler to shut off. Seems like this valve should have lasted longer. Trying an Apollo brand this time.
Showing 1-10 of 96 reviews
Great replacement
Exact replacement for an older version
Steve
San Antonio TX
3 months ago
Verified Buyer
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Bad relief valve
This product is bad it's leaking water.
Alaa
Baltimore, MD
6 months ago
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Quick and dependable
Relief valve for my boiler
Jerry
Chicago ill
7 months ago
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Perfect replacment
It was a perfect fit for my oil burner.
Ricky
nj
7 months ago
Verified Buyer
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Perfect
Works well and easy to install
GdH
Momma's house
1 years ago
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H yes
Easy installation only took me about 15 minutes
Mike
Manchester pa
2 years ago
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I would buy this product again.
Part was a perfect fit. No issues
John
Ohio
2 years ago
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Great product - great service - would buy again
on my boiler - works great as it should
Old Biker
Maine
2 years ago
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I would buy again
Fit / Worked perfect
FLC
Bozeman, MT
2 years ago
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I would buy the male next time
Quality product, but needed a nipple due to my error in ordering
Bion
Webster, NH
2 years ago
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Product Q&A
5 Questions5 Questions
Q: Is this suitable for steam?
Asked by Tyler 8 years ago
Add your answer
Verified Reply- Supplyhouse.com TeamYes, this pressure relief valve is suitable for steam. If you want more specs, please check out this link to Watts' page: https://www.watts.com/products/plumbing-flow-control-solutions/relief-valves/asme-safety-valves/335/m335m2-030-34
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Verified Reply- Supplyhouse.com TeamYes, this pressure relief valve is suitable for steam. If you want more specs, please check out this link to Watts' page: https://www.watts.com/products/plumbing-flow-control-solutions/relief-valves/asme-safety-valves/335/m335m2-030-34
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Q: is this pressure valve used on hot water tanks only? Can it be used on Utica furnaces?
Asked by frankie 9 years ago
Add your answer
Verified Reply- SupplyHouse StaffThis relief valve has a 30psi setpoint, which is typical for boilers. As long as the BTU capacity meets or exceeds that of the boiler it should work fine.
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Q: My pressure relief valve leak will replace with same will this replacement of a new valve stop the leak
Asked by Boil 10 years ago
Add your answer
Verified Reply- SupplyHouse StaffTypically relief valves will drip or leak when the pressure in the system is nearing, but not reaching the valve set point. If this is the case, the new one would leak as well because there is a problem elsewhere in the system.
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Q: Will this work on a Vaillant oil fired boiler closed hydronic heating system?
Asked by Stasha 10 years ago
Add your answer
Verified Reply- SupplyHouse StaffYes, so long as the BTU capacity meets or exceeds that required by the boiler manufacturer.
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Q: how do i know if i need the male or the female Watts m335 pressure relief valve?
Asked by Tim the plumbers son 13 years ago
Add your answer
Verified Reply- PexSupply StaffIt depends on the piping/threading to which you plan to connect the valve. Male connections would be needed to connect to female threads, etc.
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- charlie
supplyhouse used the same picture to describe both the male and female m335m2 relief valve. it is my opinion that the female would appear to have both female inlet and outlet. The picture shows the male which has a male inlet and female outlet. calling the sales rep when you place the order is normal procedure. happy holidays.
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