Step 4 — understand thermostat operation, Step 5 — check thermostat operation – Bryant LEGACY LINE--RNC T1--PHP User Manual

Page 3

Advertising
background image

3

Option 13 -- Room Air Temperature Offset
Selections: ±5_F/±3_C. Default is 0.
The number of degrees to be added to the displayed temperature to
calibrate or deliberately miscalibrate the measured room

temperature. This option is in _F even if Option 3 is set for _C.

Step 4 — Understand Thermostat Operation

Temperature Display
Thermostat will display room temperature until UP or DOWN
button is pressed. The words SET TEMP appear when these

buttons are pressed and the current setpoint is displayed. If no

buttons are pressed for 5 sec, the display will change back to show
room temperature.
Backlighting
Continuous backlighting is not available. The backlight will come

on for 10 seconds after any button press. Without AC power and
when the battery is low, the backlight will remain off with button

presses.
Battery Indicator
A battery indication icon on the display shows nothing, half, or
low/no battery condition. If the battery is full or operation is from

AC power, no icon appears. Under battery operation, if the battery

is half full, a half full battery icon appears. As the battery depletes
below half, the icon remains at half, but the 10 second backlight

disappears. When the battery is absent or depleted, the display goes
blank except for an empty battery icon and all outputs are turned

off.
Timeguard Timer
A 5--minute timeguard is built into the thermostat immediately
upon power up, and any time the compressor turns off. The

compressor will not turn on until the timeguard has expired. The

timeguard affects only compressor operation. Pressing UP and
FAN buttons simultaneously will override the timeguard for 1

cycle. If PTAC operation (PH or PC) is selected under Option 1,
the timeguard timer is eliminated.
Cycle Timer
In normal heating and cooling operation the thermostat will not

allow more than 4 equipment cycles per hour (or 1 cycle every 15
minutes). Both the Y and W outputs have a 15--minute timer that

starts counting down when the output is turned on, (e.g., if Y

output is turned on for 9 minutes and then satisfies, it cannot turn
back on for another 6 minutes regardless of demand). However,

pressing UP and FAN buttons simultaneously or changing the
setpoint will override the timer for 1 cycle.
Minimum on Timer
Once the equipment has turned on, it will remain on for a

minimum of 3 minutes regardless of demand. However, the
equipment can turn off in less than 3 minutes if a change in

setpoint, or a change in mode occurs.
Staging Timer
If the thermostat is a heat pump model, it has 2--stage heat

capability. In normal operation there is a 15--minute delay between
the first and second stages of heat. The Y output will energize first,

then 15 minutes later, W is allowed to come on if the thermostat
determines it is not satisfying the demand.

However, if the heating demand is greater than 5_F/2.8_C, there
will be only a 30 second delay before bringing on W.
Auxiliary Heat Indicator
When operating a heat pump and either auxiliary heat or

emergency heat is active, a front mounted LCD indicates this
condition.

A07821

Error Messages
If the room temperature sensor fails, two dashes (----) will appear in

the temperature display and all heating and cooling outputs will be
turned off. The thermostat must be replaced.
If the internal non--volatile memory fails, E4 will alternately flash

with the temperature on the display and all heating and cooling
outputs will be turned off. The thermostat must be replaced.

Step 5 — Check Thermostat Operation

Fan Operation

1. Press FAN button. This will start continuous fan operation.

FAN ON icon will turn on.

2. Press FAN button again. This will stop continuous fan

operation. FAN ON icon will turn off.

Heating Operation

1. Press H/C button until HEAT is displayed.
2. Press UP button until LCD readout reads 3_F/1.7_C above

room

temperature.

Press

UP

and

FAN

buttons

simultaneously to defeat timers. Heating system should

begin to operate immediately.

3. For HP thermostats only, press H/C button until EMHT

(emergency heat) appears. Press UP and FAN buttons
simultaneously to defeat timers. Emergency heating (W is
ON, Y is OFF) should begin immediately.

Cooling Operation

1. Press H/C button until COOL is displayed.
2. Press DOWN button until LCD readout reads 3_/1.7_C

below room temperature. Press UP and FAN buttons
simultaneously to defeat timers. Cooling system should

begin to operate immediately.

Table 1 shows the thermostat outputs for each available stage of

heating or cooling. It may be useful in checkout or
troubleshooting.

T1

--

PA

C

/T1

--

PH

P

Advertising
This manual is related to the following products: