---
product_id: 537407633
title: "MFG 3/4\" Brass Pressure Relief Valve – 100 PSI Water System Safety Valve, NPT Thread, Durable Corrosion-Resistant Design for Well, Plumbing & Irrigation Systems"
brand: "merrill"
price: "R896"
currency: ZAR
in_stock: true
reviews_count: 4
category: "Merrill"
url: https://www.desertcart.co.za/products/537407633-mfg-3-4-brass-pressure-relief-valve-100-psi-water
store_origin: ZA
region: South Africa
---

# 100 PSI Max Pressure 3/4" NPT Threaded Connection Lead-Free Brass & Stainless Steel Springs MFG 3/4" Brass Pressure Relief Valve – 100 PSI Water System Safety Valve, NPT Thread, Durable Corrosion-Resistant Design for Well, Plumbing & Irrigation Systems

**Brand:** merrill
**Price:** R896
**Availability:** ✅ In Stock

## Summary

> 🛠️ Elevate Your Water Safety Game — Because Your System Deserves the Best!

## Quick Answers

- **What is this?** MFG 3/4" Brass Pressure Relief Valve – 100 PSI Water System Safety Valve, NPT Thread, Durable Corrosion-Resistant Design for Well, Plumbing & Irrigation Systems by merrill
- **How much does it cost?** R896 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.co.za](https://www.desertcart.co.za/products/537407633-mfg-3-4-brass-pressure-relief-valve-100-psi-water)

## Best For

- merrill enthusiasts

## Why This Product

- Trusted merrill brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Universal 3/4" NPT Thread:** Seamlessly integrates with standard plumbing, well, and irrigation systems for hassle-free installation.
- • **Certified Safety Assurance:** IAMPO and NSF/ANSI 372 certified for trusted quality and peace of mind in every use.
- • **Precision Pressure Control:** Engineered to safely relieve excess pressure up to 100 PSI, protecting your plumbing system with confidence.
- • **Cold Water System Optimized:** Specifically designed for cold water applications, ensuring reliable operation without compromise.
- • **Premium Lead-Free Brass Construction:** Durable, corrosion-resistant design ensures long-lasting performance and compliance with health standards.

## Overview

The Merrill MFG 3/4" Lead-Free Brass Pressure Relief Valve is a high-quality, corrosion-resistant safety valve designed for cold water systems. Featuring a 3/4" NPT threaded connection and a maximum pressure rating of 100 PSI, it ensures reliable pressure relief to protect plumbing, well, and irrigation setups. Certified by IAMPO and NSF/ANSI 372, this valve combines durability with compliance, making it an essential upgrade for professional-grade water system safety.

## Description

Buy Merrill MFG 3/4" Brass Pressure Relief Valve – 100 PSI Water System Safety Valve, NPT Thread, Durable Corrosion-Resistant Design for Well, Plumbing & Irrigation Systems: Relief Valves - desertcart.com ✓ FREE DELIVERY possible on eligible purchases

Review: Good quality - Item worked as new original
Review: So far, so good - Does what it should (I hope). Amazingly, my well pump system did not have a safety relief valve.

## Features

- Pressure relief valves are for protection against excessive pressure
- 3/4 in. male NPT x 3/4 in. female FPT
- Lead free brass with stainless steel control springs - IAMPO Certified
- 3/4" Line Connection, 100 PSI
- Not for use with water heaters -Cold water systems only
- CALIFORNIA PROP 65 WARNING: Product may expose you to chemicals known to the State of California to cause cancer and reproductive harm. See P65Warnings.ca.gov for details

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0BW4Z38VV |
| Best Sellers Rank | #90,201 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #64 in Relief Valves |
| Brand | Merrill |
| Brand Name | Merrill |
| Connector Type | Threaded |
| Customer Reviews | 4.4 out of 5 stars 41 Reviews |
| Exterior Finish | Stainless Steel |
| Inlet Connection Size | 0.75 inches |
| Inlet Connection Type | National Pipe Tapered |
| Item Dimensions | 2.47 x 1.45 x 1.05 inches |
| Item Type Name | No Pressure Relief Valve |
| Item dimensions L x W x H | 2.47 x 1.45 x 1.05 inches |
| Manufacturer | Merrill Manufacturing Company |
| Manufacturer Part Number | PRVNL757100-A |
| Material | Brass |
| Material Type | Brass |
| Maximum Operating Pressure | 100 psi |
| Model Number | PRVNL757100-A |
| Number of Items | 1 |
| Number of Packs | 1 |
| Number of Pieces | 1 |
| Number of Ports | 2 |
| Outlet Connection Size | 0.75 inches |
| Outlet Connection Type | MNPT |
| Size | 0.75 Inch |
| Specification Met | IAMPO, NSF/ANSI 372, AB 1953 |
| Thread Size | 3/4 inch |
| Thread Type | NPT |
| UPC | 642367453541 |
| Unit Count | 1 Count |
| Valve Type | Pressure Relief Valve |

## Product Details

- **Brand:** Merrill
- **Exterior Finish:** Stainless Steel
- **Inlet Connection Size:** 0.75 inches
- **Inlet Connection Type:** National Pipe Tapered
- **Item dimensions L x W x H:** 2.47 x 1.45 x 1.05 inches
- **Material:** No lead Brass
- **Maximum Operating Pressure:** 100 psi
- **Number of Ports:** 2
- **Outlet Connection Size:** 0.75 inches
- **Outlet Connection Type:** MNPT

## Images

![MFG 3/4" Brass Pressure Relief Valve – 100 PSI Water System Safety Valve, NPT Thread, Durable Corrosion-Resistant Design for Well, Plumbing & Irrigation Systems - Image 1](https://m.media-amazon.com/images/I/214dX4hFjNL.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ Good quality
*by E***P on March 29, 2026*

Item worked as new original

### ⭐⭐⭐⭐⭐ So far, so good
*by A***T on September 17, 2025*

Does what it should (I hope). Amazingly, my well pump system did not have a safety relief valve.

### ⭐⭐⭐⭐⭐ I was told by my plumber that these should be inspected yearly.
*by G***4 on October 20, 2023*

Well who knew these things should be inspected yearly and replaced after 10 years. They stop your pipes or water heater from going boom splash. This one is for cold water only and was fitted to our pump. In the event that our filters get blocked it lets the excess water pressure out preventing the above mentioned water disaster. We had to buy a different version with a test handle for our hot water heater.

## Frequently Bought Together

- Merrill MFG PRVNL757100-3/4" Lead-Free Pressure Relief Valve, 100 PSI, Brass, NPT,
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- SENCTRL 100 Psi Lead-Free Glycerin Liquid Filled Low Pressure Gauge, 2.5" Dial Size, 1/4" NPT Lower Mount, Stainless Steel Case, for Home Potable Water Pump, Air, Well, RV Hose, Pressure Test

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*Product available on Desertcart South Africa*
*Store origin: ZA*
*Last updated: 2026-10-31*