Standard Duty Flow Test Kit – Model 843


Range: 0-10" H2O thru 0-100 PSID
Rugged (2) gauge medium duty portable flow test kit. This kit is equipped with two differential pressure gauges with complimentary dials ranges, enabling it to cover a broad range differential pressures and accuracies from ±5% to ± 3-2-3% full scale (ascending). Both gauges are protected against over-range to the maximum working pressure of the test kit. While primarily used for balancing HVAC systems it has numerous other applications which include but are not limited to: checking pump performance, checking pressure drop across filters, leakage, etc…

Product Features and Benefits

  • Over 30 Years of Input from Professional Testing Technicians
  • Combination kit includes both 820 & 841 Flow test gauges
  • 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
  • Test Procedures are Laminated in Clear Plastic
  • 5 Year Warranty


  • Gauge Type: (2) "Diaphragm" Differential Pressure
  • Dial size: (2) 4-1/2"
  • Range: 0-10" H2O thru 0-100 PSID ranges available
  • Differential Pressure Accuracy: ±5% Full Scale (Ascending) 0-10" thru 0-400" H2O
    ±3-2-3% Full Scale (Ascending) 0-400" H2O thru 0-100 PSID
  • Working Pressure: 300 PSIG (Standard)
  • Gauge Material: (1) Engineered Plastic Body (1) Aluminum Body & 316 S.S. Internals
  • Wetted Internals: Buna-N Seal & Diaphragm, Plastic, Aluminum & S.S., Brass
  • Hoses & End Fittings: Nitrile Jacket and liner. Schrader 1/4" brass coupler (Connects with 1/4" 37° Flare Male Fittings).
  • Tubing & Fittings: Nylon & Brass
  • Hose Length: 5' long (1.5 meter)
  • Filters: 90 Micron Brass (Order Replacement Filter Kit No. 98008)
  • Aproximate shipping wgt: 12 lbs / 5.5 kgs
  • Case: Polyethylene
  • Dimensional Data: 16.5" x 7.25" x 9"
  • Temperature Limitations: Maximum 150°F/65°C

    Freezing Temperatures must be avoided


Standard Duty Flow Test Kit - Model 843

  Your Price: $1,035.00 Quantity:
  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 and green low pressure hose downstream
  2. Open valves on device being tested and read differential.
  3. Upon completion of test close valves, disconnect hoses and store them in test kit case.

NOTE: The 843 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 843 Test Kit Schematic Diagram