Mark II Molded Plastic Air Filter Gages - Series-25- 40

FEATURES Dwyer Mark II molded air filter gages are of the inclined and inclined-vertical types. The curved inclined-vertical tube of the Model 25 gage provides higher ranges with more easily read increments at low readings. The Model 40 inclined gage provides linear calibration and excellent resolution throughout its range. When ordered with the Model A-606 AF Kit the Model 40 is ideally suited for stationary air filter gage applications. The Model 25 is excellent for general purpose work and for higher anticipated filter resistances. Both gages are capable of measurements above and below atmospheric as well as differential pressure measurements.
Construction - Mark II air filter gages are economically priced, compact and available in both stationary and portable configurations. Portable stand is standard on Model 40, available as optional A-612 stand for Model 25. Construction is simple with virtually indestructible molded white styrene acrylonitrile housing, indicating tube and fluid wells, molded ABS knobs and zero adjust plunger, shock mounted glass level vial and leak proof "O" ring seals. Moderate overpressures are accommodated by an overflow tank incorporated in the Model 25. Greater protection is provided by float operated overflow traps in the Model 40. Scales are lithograph printed on aluminum and epoxy coated.

CONSTRUCTION Dwyer DURABLOCK® Series 250-AF Gages are precision machined 1" thick solid acrylic plastic, virtually unbreakable and free of distortion. The fluid bore is precision drilled to ±.0002" to assure life long accuracy. A glass spirit level is built into the body and encapsulated to prevent damage or tampering. The scale is mirror polished chrome plated brass to assure parallax free reading by alignment of the miniscus with its reflection. Safety traps are incorporated in the body to prevent loss of fluid due to pressure surges. Red and green signal flags indicate clearly when a filter change is necessary. Gages are suitable for use in ambient temperatures of -20° to +150°F. connection fittings are positively sealed by "O" rings but easily removed for zeroing or addition of fluid. Furnished complete with instructions.

Installation

For normal stationary installations, simply mount the gage on any vertical surface with the two mounting screws provided. A built-in spirit level simplifies leveling before mounting screws are tightened. Fill the reservoir, adjust fluid level to zero, connect the tubing, and the gage is ready for operation.
Accessories - Included with each Mark II air filter gage are two tubing connectors for 1/8" pipe or sheet metal ducts, two mounting screws, ¾ oz. Bottle of indicating fluid, red and green pointer flags and complete instructions. The Model 25 includes 8' of flexible double column plastic tubing. The Model 40 includes two 4 ½' lengths of clear plastic tubing and is equipped with rapid shut-off connectors. The optional Model A-606 AF Kit (for use with the Model 40 only) contains two static pressure tips with integral compression fittings, two 5' lengths of aluminum tubing and two slip-fit gage compression fittings which can be easily removed to zero the gage.
SUGGESTED SPECIFICATIONS An air filter gage for measuring the resistance to air flow through the filters shall be installed: one for each bank of filters. The air filter gage shall be one-piece molded plastic construction, manometer type, with epoxy coated aluminum scale, inclined-vertical indicating tube and built-in spirit level. Red and green signal flags to mark dirty and clean filter indications shall also be provided. Gage shall be Dwyer Instruments, Inc. Mark II Catalog No.____ reading to __inches of water.

FACTORY STOCKED MODELS

	Model	Range Water Column	Fluid Used
	25 26 MM-80 MM-180 M-700Pa	0-3 in. w.c. 0-7 in w.c. 0-80mm w.c. 0-180mm w.c. 10-0-700 Pa	Red oil, .826 s.g. Blue oil, 1.91 s.g. Red oil, .826 s.g. Blue oil, 1.91 s.g. Red oil, .826 s.g.

FACTORY STOCKED MODELS

	Model	Range Water Column	Fluid Used
	40-1 40-25mm 40-250 Pa3 41-2 41-60mm 41-600 Pa	.1-0-1.0 in w.c. 0-26mm w.c. 10-0-250 Pa .2-0-2.4 in. w.c. 0-60mm w.c. 20-0-600 Pa	Red oil, .826 s.g. Red oil, .826 s.g. Red oil, .826 s.g. Blue oil, 1.91 s.g. Blue oil, 1.91 s.g. Blue oil, 1.91 s.g.