HVACCONT-A Controls Heating and Air-Conditioning Central System - Annual

                                                      Man Hours .25
Special Instructions:

1.  Read and understand manufacturer's instructions before making adjustments or
2.  Obtain control system diagrams.
3.  Before calibrating or adjusting pneumatic controls, adjust the pressure of
    the main control air supplying pneumatic sensors, thermostats, and
    controllers to manufacturer's specifications.
4.  Servicing of pneumatic air compressors and control air reducing stations
    shall be performed at the same time to prevent duplication of some service
    check points.

Items to Check & Initial Completion:

1. ___ Check set point of controls (temperature, humidity, or pressure).
2. ___ Compare control point with an external measuring device, note deviations,
       and adjust.
3. ___ Check the unit over its range of control.  If possible, impose simulated
       conditions to activate controls and check operation.
4. ___ Check for control point cycling.
5. ___ Check for correct pressure differential on all two position controllers
6. ___ Check condition and action of primary elements in the controllers
       (bi-metallic strips, and or sealed bellows with capillary tubing for
       remote sensing.
7. ___ Note the action of the controlling device (thermostats, humidistats, and
       pressurestats) which changes the action of the controlled device (motors,
       valves, dampers, etc.)
8. ___ On electronic controls check the source of the signal and its
9. ___ Check air systems for leaks, check for correct main control air pressure
       to control devices.  Check units for proper closing and loose connections.
10.___ Check the condition and the ability of humidity sensing
       control elements (hair, wood, leather, or similar substances) to  read the
       moisture changes and their action on the control  mechanism.
11.___ Check resulting action of the pressure sensing primary
       control elements such as diaphragms, bellows, inverted bells, and similar
       devices when activated by air, water, or similar pressure.  Check
       operation of all relays, pilot valves, and pressure regulators.
12.___ Replace air filters in sensors, controllers, and thermostats as required.
13.___ Use test kits and manufacturer's instructions whenever
       possible.  Replace rather than rebuild a control installed in the system.
       Take control to shop for repair.

Tools & Materials:

1.  Standard Tool Kit
    Plus  Insulated pliers and screwdrivers
          Wire strippers
          Wire crimpers
          Voltmeter - Ohmmeter - Milliammeter
          Clamp on meter(volt - ohm - amp meter)
          Soldering kit
          1/8" 25' fish tape
          Burnishing tool
2.  Pressure gauge, psychrometer
3.  Volt Ohm Meter
4.  Air filter replacements
5.  Control spares as needed

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