The Dwyer LFMF-16-I2 is a Series LFM polycarbonate variable area flowmeter that measures water flow from 5 to 45 GPM (20 to 180 LPM) on an 11 in. (279 mm) dual-scale, direct-reading body with 2 in. in-line male NPT connections.
The LFMF-16-I2 pairs an injection molded polycarbonate body with a 316 SS rod and float, a polypropylene float stop and standard 2 in. male NPT fittings in PA66 nylon, weighing 40 oz (1.1 kg). An adjustable set point indicator option is offered for this body size. Series LFM flowmeters are for indoor use only or areas without direct sunlight, because polycarbonate is adversely affected by ultraviolet light.
Specifications sourced from the Dwyer Series LFM catalog page (LFM_1, p. 253) and the Series LFM instruction manual, Bulletin V-31 (FR# R4-443531-00 Rev. 1). Last verified October 14, 2026.
Best For
- Direct reading of water flow from 5 to 45 GPM (20 to 180 LPM)
- Chill water flow monitoring
- Reverse osmosis systems
- Deionized water systems
- Indoor installations away from direct sunlight
Warranty
DwyerOmega limited warranty: free from defects in material and workmanship under normal use for one year from delivery to the buyer, or such other period as specified in a product-specific warranty supplied with the product.
Key Features
Dual GPM and LPM Scale
The 11 in. (279 mm) scale reads 5 to 45 GPM and 20 to 180 LPM directly, with a textured background behind the scale for easier reading.
Polycarbonate Body, 316 SS Float
Heat and chemically resistant injection molded polycarbonate body with a 316 SS rod and float, fluoroelastomer O-rings and an ABS flange nut.
Male NPT In-Line Connections
Standard 2 in. male NPT connections on both ends install directly in-line. Optional A-565 63 mm metric union fittings and A-574 2 in. female NPT fittings are available.
Adjustable Set Point Indicator Option
An adjustable set point indicator option is offered for the LFMF body size, giving a quick visual reference that reduces flow reading errors.
Removable Body for Cleaning
The body removes quickly with all fittings left intact. Clean with mild soap and a bottle brush; no other routine maintenance is required.
NIST Calibration Certificate Option
Order code NISTCAL-FL2 adds an NIST traceable calibration certificate for variable water flowmeters.
ZOT Supply is an authorized distributor of Dwyer products.
Technical Specifications
| Model | LFMF-16-I2 |
| Series | LFM (LFMF body) |
| Service | Water |
| Flow Range | 5 to 45 GPM water |
| Metric Flow Range | 20 to 180 LPM water |
| Scale | 11 in. (279 mm), dual GPM and LPM, direct reading |
| Accuracy | ±5% full scale |
| Pressure Limit | 87 psi (6 bar) at 68°F (20°C) |
| Temperature Limits | Varies with pressure; see the temperature vs. pressure chart in the instruction manual |
| Process Connection | 2 in. male NPT, both ends |
| Standard Fittings | 2 in. male NPT (A-571), PA66 nylon |
| Optional Fittings | A-565 63 mm metric union fittings (ABS); A-574 2 in. female NPT fittings (nylon) |
| Mounting | In-line |
| Body | Polycarbonate |
| Flange Nut | ABS |
| Float Stop | Polypropylene |
| Rod and Float | 316 SS |
| O-Rings | Fluoroelastomer |
| Set Point Indicator | Adjustable set point indicator option |
| Overall Length | 15-3/4 in. (400.05 mm) |
| Diameter | 3-15/16 in. (100.01 mm) |
| Weight | 40 oz (1.1 kg) |
| Calibration Option | NISTCAL-FL2: NIST traceable calibration certificate for variable water flowmeters |
| Installation | Indoor use only or areas without direct sunlight |
Documentation
Frequently Asked Questions
What is the flow range of the Dwyer LFMF-16-I2?
The LFMF-16-I2 measures 5 to 45 GPM (20 to 180 LPM) of water on an 11 in. (279 mm) dual GPM and LPM scale.
What process connection does the LFMF-16-I2 have?
The LFMF-16-I2 has 2 in. male NPT connections on both ends. Optional fittings: A-565 63 mm metric union fittings (ABS); A-574 2 in. female NPT fittings (nylon).
How accurate is the LFMF-16-I2?
Accuracy is ±5% full scale.
What is the pressure limit of the LFMF-16-I2?
The pressure limit is 87 psi (6 bar) at 68°F (20°C). The limit varies with temperature. Ball valves and solenoid valves can create a water cannon effect on opening that exceeds the rated limits and damages the flowmeter.
Is a set point indicator available for the LFMF-16-I2?
Yes. An adjustable set point indicator option is offered for the LFMF body size for visual set point indication.
Can the LFMF-16-I2 be installed outdoors?
No. Series LFM flowmeters are for indoor use only or areas without direct sunlight, because polycarbonate is adversely affected by ultraviolet light.
How should the LFMF-16-I2 be installed?
Install it in an exact vertical plane aligned with the existing plumbing, with wall or structural supports at the top and bottom so the flowmeter does not carry the weight of the pipes. Hand-tighten the flange nut connection rings and use plumbers tape, not pipe dope, which can craze and crack the housing.
Is NIST traceable calibration available for the LFMF-16-I2?
Yes. Order code NISTCAL-FL2 adds an NIST traceable calibration certificate for variable water flowmeters.
What are the wetted materials of the LFMF-16-I2?
Polycarbonate body, ABS flange nut, polypropylene float stop, 316 SS rod and float, fluoroelastomer O-rings, and PA66 nylon standard fittings.
- Series:
- LFM
- Product Type:
- Variable Area Flowmeter
- Media:
- Water
- Flow Range:
- 5-45 GPM
- Connection Type:
- Male NPT
- Connection Size:
- 2 in.
- Body Material:
- Polycarbonate
- Max Pressure:
- 87 psi
- Accuracy:
- ±5% FS
- Mounting:
- Vertical
- NIST Calibration:
- Available
