Overview
Rugged 3/4" multi-jet water meter with reliable accuracy across flow rates.
The MJ20 3/4" is a robust multi-jet water meter that combines best-in-class multi-jet metering technology with a rugged body design, delivering consistent, reliable water flow measurement across a wide range of flow rates.
Available in both hot and cold models, the MJ20 3/4" is purpose-built for multi-family submetering. Each meter undergoes rigorous, state-of-the-art testing during manufacturing to meet both AWWA standards and NTEP certification, providing unwavering quality that you can trust.
Equipped with built-in mounting plates and a pre-wired connector, the MJ20 3/4" easily pairs with a wireless Next Meters Transceiver to integrate with the NextCentury platform. This connectivity, backed by exceptional support, allows for easy water usage monitoring from anywhere.
Designed for flexibility, the MJ20 3/4" can be installed horizontally or vertically without compromising the meter's accuracy or longevity, and its wrench-friendly design streamlines the setup process.
Specifications
Connectivity
| Wired Output | Pulse output – dry contact (1 pulse / 10 gallons) Pre-installed connector and mount for Next Meters Transceiver |
|---|---|
| Wireless Communication | Pairs with the Next Meters Transceiver (TR4) Built-in Transceiver mounting plate and pre-wired connector Integrates with the NextCentury platform |
Physical and power
| Dimensions | Lay length: 7.5” | 190.5 mm Width: 2.75” | 70 mm Height: 3.93” | 100 mm Connection: 1” NPSM |
|---|---|
| Operation Environment | MJ20 3/4” C: 36° F | 2° C to 105° F | 40° C MJ20 3/4” H: 36° F | 2° C to 194° F | 90° C Up to 150 PSI operating pressure Low head loss: less than 5 PSI at 15 GPM Indoor installation only Up to 90% non-condensing humidity |
Certifications
| Approvals | NTEP/CTEP Approval 24-039 Meets AWWA C708 accuracy & performance NSF/ANSI/CAN 61 & 372 certified |
|---|
More details
| Installation | Horizontal or vertical Register facing up or 90º from upright when horizontal Maximum 5º variance from horizontal or vertical Max coupling torque of 15 lb•ft Cold (C) and hot (H) water meter models available |
|---|---|
| Applications | ¾” x ¾” | 1” NPSM Connection | 7 ½” lay length Continuous flow 15 GPM | Max flow 30 GPM Registers flow as low as 0.2 GPM Multi-family and commercial submetering |
| Warranty | 5-year standard warranty from date of manufacture |
Installation
Installation
Confirm a qualifying installation
Before installing, verify that the location and plumbing system meet the following requirements.
- The meter location must have sufficient finished clearance to allow for reading, inspection, and eventual replacement of the meter.
- Building plumbing engineering must comply with local building code and effectively prevent backflow through system design, which may include backflow prevention check valves.
- The plumbing system should include a shutoff valve upstream of the meter to allow for future maintenance of the meter and other plumbing components.
- When electrical grounding of the water supply line is required, an approved bonding jumper should be installed.
Caution
Do NOT use pipe dope on the threads of the meter.
Prepare the supply line
Shut off the water line and carefully remove the spacer tube or existing meter from the line.
Ensure gaskets are in place and undamaged. Replace them if needed.
Note
Each MJ20 3/4” requires two gaskets (sold separately). Use new gaskets any time a meter is installed or replaced. For cold water applications, use EPDM peroxide-cured gaskets. For hot water applications, use fiber gaskets.
Ensure correct spacing
Verify that the water line is parallel and has enough space for the meter. The MJ20 3/4” fits a standard lay length of 7.5” or 190.5 mm.
Caution
Spacing should allow for the meter without pushing, pulling, or kinking the line.
Check flow direction and orientation
The meter must be installed in the correct direction of flow. The flow direction arrows can be seen on both sides of the meter.
The MJ20 3/4” can be installed horizontally or vertically. When installed horizontally, the register must face up or 90º from upright. The maximum degree of variance from precisely horizontal or vertical is 5º.
Caution
Do NOT install the meter horizontally with the register facing down, or at any rotation other than upright / 90º from upright.
Secure the MJ20 3/4”
Place the meter and tighten both ends to a maximum torque of 15 lb•ft. Hold the meter steady to prevent unwanted rotation.
Caution
Do NOT overtighten meter couplings as this may result in the gaskets not forming a proper seal.
Pressurize the line and check for leaks
Before exposing the meter to full flow conditions, ensure all air is expelled from the piping. Gradually turn the water line back on to prevent damage to the meter, then inspect all connection points for moisture to confirm a watertight seal.
Note
The MJ20 3/4” will begin accurately measuring flow once air has evacuated and water has completely filled the line.
(Optional) Integrate with a Transceiver
The MJ20 3/4” seamlessly integrates with a Next Meters Transceiver using its built-in mounting plate and pre-wired connector.
To pair the meter with a Transceiver, consult the Quick Start Guide included with the Transceiver for wiring and programming instructions.
Note
For more information about the Transceiver, including specifications and installation guidelines, visit products.nextmeters.com/tr4 or contact your distributor.
FAQ
The MJ20 3/4” is a robust multi-jet water meter that provides consistent, reliable water flow measurement at a variety of flow rates. Available in both hot and cold models, it is perfectly suited for multi-family submetering and pairs with a Next Meters Transceiver to integrate with the NextCentury platform.
Key benefits
- Hot and cold meter models available
- Built-in Transceiver mounting plate
- Robust body design offers extended meter longevity
- Sealed register prevents tampering
- Best-in-class multi-jet technology
- Manufactured and tested in a state-of-the-art facility
- Designed for easy installation
The MJ20 3/4” has the following:
- NTEP/CTEP Approval 24-039
- Meets AWWA C708 accuracy & performance
- NSF/ANSI/CAN 61 & 372 certified
Here are some tips for installing the MJ20 3/4”:
- Indoor installation only
- Up to 90% non-condensing humidity
- Horizontal or vertical installation
- When installed horizontally, the register must face up or 90º from upright
- Standard 7.5” (190.5 mm) lay length with 1” NPSM connections
- Maximum coupling torque of 15 lb•ft
- Water must flow in the direction indicated by the arrows on the meter
For the full installation process, follow the guide here: MJ20 3/4” Installation
The MJ20 3/4” features a dry contact pulse output rated at 1 pulse per 10 gallons. It also ships with a pre-installed connector and mounting plate for a Next Meters Transceiver, allowing the meter to communicate wirelessly with the NextCentury platform for easy water usage monitoring from anywhere.
The MJ20 3/4” C is the cold water model and the MJ20 3/4” H is the hot water model. Both share the same dimensions and performance characteristics, but they support different water temperature ranges:
- MJ20 3/4” C: 36° F | 2° C to 105° F | 40° C
- MJ20 3/4” H: 36° F | 2° C to 194° F | 90° C
Each MJ20 3/4” requires two gaskets (sold separately). Always use new gaskets when installing or replacing a meter, and replace a gasket anytime a coupling is loosened before it is tightened back down.
- Cold water applications: EPDM peroxide-cured gaskets. Expected life is 10 to 20 years depending on water quality — lower chloramine levels result in longer life expectancy.
- Hot water applications: fiber gaskets. Expected life is 10 years or more.
Fiber gaskets are preferred over EPDM for many hot water meters due to their superior performance under high pressure, high thermal stability, and better torque retention. While EPDM is excellent for cold or moderate-temperature water, fiber gaskets offer better rigidity and resistance to thermal degradation at higher temperatures.
The MJ20 3/4” registers flow as low as 0.2 GPM and supports a continuous flow rate of 15 GPM with a maximum flow rate of 30 GPM. Head loss stays low across the operating range at less than 5 PSI at 15 GPM.
The MJ20 3/4” has a rated maximum operating pressure of 150 PSI, which far exceeds standard water supply specifications. Its pressure endurance is verified using accelerated-life testing, in which the meter is pressurized to 300 PSI across 100,000 cycles (see AWWA C708).
Note
Multi-family and commercial water distribution systems must be designed with careful consideration to prevent pressure spikes that exceed maximum pressure requirements. All plumbing components, fixtures, and appliances typically are required to withstand 2x the nominal static water pressure.
Yes. The MJ20 3/4” is tested and certified to NSF/ANSI/CAN 61 and 372 standards for drinking water system components. These certifications ensure the meter is free from harmful contaminants and can operate efficiently without posing any health risks.
No. The MJ20 3/4” uses a lead-free sealing system, eliminating the traditional lead seal used on most water meters. This removes a known health hazard from the potable water system entirely, reinforcing the same drinking-water safety standard verified by the meter's NSF/ANSI/CAN 61 and 372 certifications.
Note
Because the MJ20 3/4” is sealed with a positive die rather than the negative die common to lead seals, utilities and inspectors should confirm the appropriate sealing tool and die with their local Weights and Measures authority.
The following can be found on the face of the MJ20 3/4”:
- Meter read and unit of measurement (U.S. gallons)
- Meter size
- Unique meter serial number
- Model
- NTEP certification number
- Multiplier, sweep hand, and flow indicator
Next Meters warrants the MJ20 3/4” meter to be free from defects in materials and workmanship for a period of five years from date of manufacture when installed in accordance with the installation instructions and with limitations as detailed in the complete warranty.
For full warranty information, please refer to the Multi-Jet Meter Warranty document.
For additional information or assistance, visit our Support Center or contact our Product Support Team:
- support.nextmeters.com
- (844) 538-8203
- support@nextmeters.com