Motion Picture Herald (Mar-Apr 1947)

CAN HELP YOU THROUGH AN EMERGENCY YOUR ALTEC ENGINEER KNOWS YOUR EQUIPMENT INSPECTION REMINDER-GUIDE Air Conditioning and Ventilation 1 — BLOWER If in operation for several months, bearing pillow blocks should be disassembled and cleaned with kerosene; check parts for uneven wear, bad mars, which may indicate improper grease or oil. Check for proper alignment of shaft (a spirit level should be used for this). Examine lag bolts or screws holding frame to foundation to be sure blower does not creep. Inspect connection from mouth of blower to duct for looseness. 2 — MOTORS Inspection follows same procedure for motors in general (variously dealt with in preceding inspection charts). To summarize: Check bearings for wear and signs of poor lubrication, also bad alignment. Examine commutator and rotor windings for cleanliness and, if rotor clearance gauges are available, test clearances between stator windings, especially if uneven operation has been noted. Check stator coil pole pieces for looseness. Tighten loose connections and be sure splices are in good condition. 3 — PULLEYS Check for looseness and travel out of line (keys should be firm in keyways and set-screws around hub turned down hard). Clean grooves. (Never strike pulley directly with hammer.) 4— DRIVE BELTS Make sure tension is not too much or too little. Check for undue flop, which may be due to misalignment of motor shaft and pulley with blower pulley. Examine for wear that may indicate replacement. (It is well to change belts around occasionally so each works in a different groove for a time.) 5 — HYDRAULIC DRIVE Some drives are of this type to provide variable speeds. It principally needs checking for breaks and bends of oil feed lever; also be sure priming pump is in good condition. 6 — AIR WASHERS, DEHUMIDIFIERS, ETC. Inspect spray nozzles for sediment, scale, rust. Check for broken feed pipes and condition of eliminator plates (if dirty, they should be washed down and given coat of rust-resistant paint). Examine makeup water tank or drip pan for cleanliness. Make sure louvres or doors over air intake operate easily and close tight. 7 — WATER PUMPS For thorough checking, housing around pump should be removed and interior drained. It should be free of sediment. Check impeller blades, packing glands, washers and coupling for defects. Give pump motor usual motor inspection. 8 — COOLING COILS Check fin surfaces for dirt and scale (never use a sharp instrument for cleaning). Make sure no fin is bent and all are clean (a steel wire brush is best for cleaning). 9 — COMPRESSORS Check piping for leaks, joints and valves for tightness, diaphragm for corrosion, refrigerant line for cleanliness, controls for proper pressure in system. Be sure expansion valves seat properly and have full charge. See that fans are interlocked with compressor. 10 — CONDENSERS General checkup is similar to that indicated for cooling coils. If putting the equipment in operation after layoff, be sure discharge and suction pressures are correct. 1 1 —THERMOSTATIC CONTROLS Check for cleanliness, tight wiring connections, pitted or fused terminals (use tiny file or sandpaper to smooth off pitted terminals). Be sure there is no penetration of moisture. 12 — DUCT SYSTEM Check for loose joints and dampers, defective sections, and general cleanliness. (NEXT MONTH: CURTAINS, DRAPES AND FABRICS) 26 BETTER THEATRES, APRIL 5, 1947