Precision Flow Test Kit – Model 805


Range: 0-10" H2O thru 0-79.9" H2O
High accuracy portable test kit for precise flow indication and leak detection. This kit is equipped with a precise (±1% of full scale) accuracy differential pressure gauge. Popular applications include but are not limited to: measuring the pressure drop across various types of equipment i.e. filters, balancing HVAC systems, checking pump performance, orifice plates, checking calibration of transmitters, or reading flow directly when ordered with a square root dial etc.

When being used the gauge should be placed in as nearly vertical position as possible. This gauge is position sensitive and accuracy may be less than stated, if not in a vertical position.

Product Features and Benefits

  • Over 30 Years of Input from Professional Testing Technicians
  • Soft-Seated Brass Needle Valves (with replaceable valve seats)
  • Test kit is protected with 90 micron filters to minimize plugging with scale, sand, etc. Filter elements can be cleaned or replaced
  • Durable Molded Plastic Carrying Case with Removable lid
  • Test Procedures are Laminated in Clear Plastic
  • 5 Year Warranty


  • Gauge Type: "Bellows" Differential Pressure
  • Dial Size: 4-1/2" Standard (6" Optional)
  • Range (4-1/2") 0-10" thru 0-79.9" H2O ranges available
  • Accuracy: ±1% Full Scale (Ascending) Std. (Accuracy: ±1/2% Full Scale available)
  • Working Pressure: 500 PSIG (Standard)
  • Gauge Material: Aluminum Body & Copper Alloy Internals
  • Wetted Internals: Buna-N Seals, Aluminum & Copper Alloy
  • Hoses & End Fittings: Nitrile Jacket and liner. Schrader 1/4" brass coupler (Connects with 1/4" 37° Flare Male Fittings)
  • Valves: Soft-Seated Brass
  • Tubing & Fittings: Nylon & Brass
  • Hose Length: 10' long (3 meter)
  • Filters: 90 Micron Brass (Order Replacement Filter Kit No. 98008)
  • Approximate Shipping Wgt: 15 lbs / 6.8 kg
  • Case: Polyethylene
  • Dimensional Data: 13.75" x 15.5" x 8.5"
  • Temperature Limitations: Maximum 150°F/65°C

    Freezing Temperatures must be avoided

Model 805 plumbed for water service only. Please contact the factory for assistance on kits for use with other liquids or gases.


Precision Flow Test Kit - Model 805

  Your Price:
(Range: 0-10", 0-20", 0-25") $1,928
(Range: 0-30", 0-40", 0-50", 0-60", 0-70") $1,697.00
  Ranges offered are some of the most popular requested today.
Mid-West Instrument can provide special dial range requirements.
Such as multiple scale dials, multiple color dials and special decals.
Please consult factory for complete information.

Replacement Filter Kit "90 Micron Brass"(Set of Six)
  No. 98008 $32.00 each Quantity:  


Functions and Applications

  1. Connect hoses to test connections – red high pressure hose upstream, green low pressure hose downstream.
  2. Open balance valve (bottom of panel)
  3. Pull free end of clear plastic tubing from kit.
  4. Open high and low bleed valves alternately to purge air from system. Bleed water discharges from convenient clear plastic flexible tubing.
  5. When bleeding shows all air removed – close bleed valves, balance valve and read differential pressure.
  6. When test is complete – open balance valve before disconnecting hoses from test connections.
  7. Hoses are stored by coiling them around the test gauge panel.
  8. Place clear plastic tubing inside case before closing lid.

For convenience in handling, the cover of the test kit is removable. Depress the pin spring of the top hinge, pull the hinge slightly apart and slide the cover off. To reinstall, reverse this procedure.

NOTE: The 805 Test Kit is equipped with in line filters near the ends of the hoses. If the gauges respond slowly to changes in the differential pressure the filter elements may be partially plugged.

To remedy this, unscrew the two halves of the filter housing and remove brass filter element. It may be cleaned by flushing with mild detergent and water. If, after reassembly this has not satisfactorily improved the response time a replacement filter element kit #98008 should be installed.

MODEL 805 Test Kit Schematic Diagram