HAI RC-122 Installation Instructions Manual

Manual is about: Two Stage Heat/Cool 2 Stage Heat / 2 Stage Cool Thermostat

Summary of RC-122

  • Page 1

    1 1 rc-122 / rc-122b two stage heat/cool 2 stage heat / 2 stage cool thermostat installation instructions description the rc-122 is a precision digital thermostat designed for 24 vac two-stage heating and cooling systems. It offers programmability, stand-alone operation, and robust, optically isolat...

  • Page 2: Figure 1

    2 2 removing an existing thermostat 1. Disconnect the power to the control transformer. 2. Remove the cover to the existing thermostat. 3. Disconnect the wires going to each terminal on the thermostat. Label each wire with the letter or number at the terminal. 4. Remove the existing plate or base fr...

  • Page 3: Figure 2

    3 3 connect each wire to the terminal strip on the thermostat base per the wiring diagram for your system application - see figures 4 - 5. Form the thermostat wiring so that the cable lies flat between the terminal strip and the center of the base. If a remote system is being used with the thermosta...

  • Page 4: Caution:

    4 4 typical wiring diagrams caution: be sure to disconnect the power to the control transformer before removing or installing thermostat. Do not short gas valve(s), fan, heat relay(s), or cool relay(s)... Even momentarily. This will blow a non- replaceable fuse. Do not attempt to hook up to live cir...

  • Page 5: Figure 5

    5 5 figure 5.

  • Page 6: Figure 6

    6 6 configuring the backlight on the rc-122b the backlight on the rc-122b can be configured to one of three different modes: 1) on for 30 seconds when a key is pressed, 2) always on, or 3) always off. 1) to configure the display backlight to turn on when a key is pressed, then back off 30 seconds la...

  • Page 7

    7 7 installer setup this section describes the items that the installer must setup as part of the thermostat installation. The installer setup mode is used to configure the general operating parameters of the thermostat. When in installer setup mode: 1. The small digits on the top of the display are...

  • Page 8

    8 8 01 communications mode the thermostat can communicate with remote systems in 4 different modes. These modes are: 0 300 baud, rs-232 mode (for use with personal computers) 1 100 baud, system mode (omnilt, omni, omni ii, omnipro, and omnipro ii systems) 8 pesm mode, (use with model 1503 automation...

  • Page 9

    9 9 04 calibration offset this item is used to raise or lower the current temperature reading by 1 degree fahrenheit or 1/2 degree celsius. If this item is set to 30, no change will be made. Each digit below 30 will lower to temperature, and each digit above 30 will raise the temperature. (1 = “- 29...

  • Page 10

    1 1 0 0 12 heating minimum on/off time (minutes) this item is the same as the “cooling minimum on/off time”, but for the heating system. The default setting is 8. 13 stage 2 differential this item specifies the temperature difference between stage 1 and stage 2. The default setting of 2 (degrees f) ...

  • Page 11

    1 1 1 1 anticipation anticipation is performed electronically and is independent of the type and load of the components in the heating and cooling equipment. This thermostat has electronic control based on proportional, integral and derivative components and maintains temperature to within 1 degree ...

  • Page 12

    1 1 2 2 remote system wiring diagrams this thermostat has been preprogrammed with energy saving settings recommended under the epa energy star program. When used with remote systems, hai recommends that the thermostat be configured as "non- programmable" (see setup item 03 - "display options"). Hai ...

  • Page 13

    1 1 3 3 note: do not connect the red comm cable wire to 12v. Figure 7 - hookup to an hai system additional thermostats are connected in parallel. They may be connected in home-run or daisy chain configuration. Remote day/night setback switches the thermostat can be connected to a remote system or re...

  • Page 14

    1 1 4 4 * red and yellow wires are not used. Insulate each using a small piece of tape. Figure 8 - hookup to remote day/night setback switch other systems for connections to personal computers, utility management systems, and other automation systems, refer to connection diagrams provided with perso...

  • Page 15

    1 1 5 5 troubleshooting tips symptom action to take 1. Check power to the thermostat 2. Check wiring diagrams thermostat dead 3. Check thermostat temperature sensor thermostat will not operate with a damaged temperature sensor symptom action to take 1. Check for break in g, w, or y wire 2. Allow min...

  • Page 16

    1 1 6 6 symptom action to take 1. Stage 1 is not able to meet the load due to severe weather stage 2 on too often 2. Eec is disabled symptom action to take 1. System may be equipped with an outdoor thermostat which is overriding stage 2 the when outdoor temperature is mild no stage 2 operation 2. St...