Table of Contents
Advertisement
25VNA4: Installation Instructions
Status Codes
Table 8
shows the status codes flashed by the amber status light. Most
system problems can be diagnosed by reading the status code as flashed
by the amber status light on the control board.
The codes are flashed by a series of short and long flashes of the status
light. The short flashes indicate the first digit in the status code,
followed by long flashes indicating the second digit of the error code.
The short flash is 0.25 seconds ON and the long flash is 1.0 second ON.
Time between flashes is 0.25 seconds. Time between short flash and first
long flash is 1.0 second. Time between code repeating is 2.5 seconds
with LED OFF.
Codes are easily read from user interface (UI) or the 5x7 LED display on
the PCM
EXAMPLE:
3 short flashes followed by 2 long flashes indicates a 32 code.
shows this to be low pressure switch open.
Status Code Recall Mode
Active status codes are stored in memory even when power is absent.
The most recent flashing status code (highest priority active) can be
recalled from memory via Status Code Recall Mode is accessed by
shorting (use a clip wire) the "force defrost" connector (labeled J2 on the
board, see
Fig.
32) and then power ON the unit.
Please make sure the unit is turned OFF before shorting the pins. Status
Code Recall Mode will continue as long as the "force defrost" terminals
remain shorted. The unit will not attempt to heat or cool while the
terminals remain shorted. Once the status code is read, power-down the
unit and remove the short.
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Emergency Mode Connections with a Conventional
Thermostat
The conventional thermostat inputs is designed to work for emergency
operation only. Connections are Y1, Y2, O, W and C. When Y1 is
energized the outdoor unit will operate at speeds equivalent to 1.5, or
median, demand. When Y1 and Y2 are energized, the system will
operate at maximum capacity.
In an emergency, it is possible to replace the UI with a conventional heat
pump thermostat (must be dual fuel capable if using a furnace), see
Fig. 32
for wiring. Refer to Step 14 for more information.
Table 8
Fig. 32 – Variable Speed Unit Connected to a Conventional Dual
Fuel Thermostat in an Emergency Mode
18
A160125
Hide quick links:
Advertisement
Table of Contents
