Step 3 — Install Light Commercial Thermidistat
Before installing Light Commercial Thermidistat, turn off all power to Weathermaster® COBRA units. There may be more than one power disconnect. Electrical shock can cause personal injury or death. Install lockout tags on disconnects.
1.Turn off all power to equipment. Tag disconnect.
2.If an existing thermostat is being replaced:
a.Remove existing thermostat from wall.
b.Disconnect wires from existing thermostat, one at a time.
c.As each wire is disconnected, record wire color and terminal marking.
d.New or additional wire may be needed to accommo- date added humidity outputs transformer common.
e.Discard or recycle old thermostat.
Mercury is a hazardous waste and MUST be disposed of properly.
3.Route wires through large hole in rear plastic. Level rear plastic (separated from front plastic in Step 2 — Set DIP Switches, on page 30). Level rear plastic against wall (for aesthetic value only — Light Commercial Thermidistat need not be leveled for proper operation) and mark wall through 2 mounting holes.
4.Drill two
5.Secure rear plastic to wall with 2 screws and anchors provided. Additional mounting holes are available for more secure mounting if needed. Make sure all wires extend through hole in mounting base.
6.Adjust length and routing of each wire to reach proper connector block and terminal on mounting base with
7.Match and connect equipment wires to proper terminals of each connector block. Remember R and C must be connected for proper operation (see Fig. 14).
Improper wiring or installation may damage Light Commercial Thermidistat. Check to make sure wiring is correct before proceeding with installation or turning on power. Refer to wiring schematic in the Troubleshooting section of this manual.
8.Push any excess wire into wall and against rear plastic. Seal hole in wall to prevent air leaks. Leaks can affect operation.
9.Reattach Light Commercial Thermidistat body to mount- ing base by first reattaching hinge.
10.Close Light Commercial Thermidistat assembly, making sure pins on back of circuit board align with sockets in connector.
11.Turn on power to equipment.
On power up, all display segments will light for 2 seconds. For the next 8 seconds, a
CP — Commercial Product
Step 4 — Set Light Commercial Thermidistat Configuration (Fig. 15 and 16) — Configuration op- tions, like DIP switch settings, are intended to be selected at installation and normally are not modified by the owner. These options must be made as part of the installation. A special procedure allows entry into the Configuration mode. While in configuration mode, up to 10 selections can be made. A description of each selection and how to use the Configuration mode are as follows:
CONFIGURATION OPTIONS — SUMMARY
Option | 1 | — Anticipator adjustment |
Option | 2 | — Clean filter timer adjustment |
Option | 3 | — English/Metric selection |
Option | 4 | — Fan (G) ON with W selection |
Option | 9 | — Holiday heat set point |
Option 10 | — Holiday cool set point | |
Option 11 — Holiday humidity set point | ||
Option 13 | — Room temperature offset adjustment | |
Option 14 | — Heat cool deadband adjustment | |
Option 21 | — Keyboard lock | |
TO ENTER CONFIGURATION MODE — Press and hold FAN button for approximately 10 seconds until COOL set point display indicates a flashing “01”. The Light Commercial Thermidistat is now in Configuration mode. It will automati- cally exit this mode if no button is pressed for 3 minutes. Press- ing HOLD End button will exit the Configuration mode immediately.
WHILE IN CONFIGURATION MODE — The upper small (COOL set point) display indicates selected option number and large display indicates selection made within that option. One of these will be flashing. The up and down set point buttons are used both to move between available options and to make selec- tion for each option. When option number (small display) is flashing, the up and down set point buttons allows for scrolling through options moving between available option numbers. After desired option number has been selected, press SET TIME/TEMP button once. The large display will now flash, indicating that up and down set point buttons now control avail- able choices within that option. Each press of SET TIME/ TEMP button switches between available option (small display) and available selections within each option (large display).
Option 1 — Anticipator Adjustment — This adjustment controls sensitivity and cycle rate of Light Commercial Ther- midistat. Higher numbers decrease sensitivity and slow cycle rate. Lower numbers increase sensitivity and cycle rate. Antici- pator values can range from 1 to 9. Factory default is 3. This default selection provides optimum performance in nearly all installations. Try it first; do not change setting unless there is evidence of need to do so.
Unlike conventional anticipators, this setting is not deter- mined by current draw. There is no need to measure, know, or compensate for current draw. There is also no droop with this Light Commercial Thermidistat. Regardless of setting and number of stages, both heating and cooling will control to their respective set points.
TO ADJUST:
1.Enter Configuration mode. The upper small (COOL set point) display will be flashing 01. If not, use up and down set point buttons to move it to 01.
2.Press SET TIME/TEMP button once to flash current selection of 1, 2, 3, 4, 5, 6, 7, 8, or 9 on large display. Factory default is 3.
3.Use up and down set point buttons to move to desired anticipator setting.
4.Press SET TIME/TEMP button again to flash small upper display for selection of another option, or press HOLD End to exit Configuration mode.
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