SERVICING
25
S-40B DV**PEC HEATER CONTROL
Description
The DV**PEC models utilize an electronic control that pro-
vides ECM blower motor control and control of up to two
electric heat sequencers. The control has thermostat inputs
for variable stage of cooling/heating, two stages of electric
heat, reversing valve, and dehumidification. Control input is
24 VAC.
Features
The new air handler control includes advanced diagnostic fea-
tures with fault recall, estimated CFM display via 7 segment
display of control board, Daikin One+™ and ComfortNetTM
ready. Diagnostics includes heater kit selection diagnostics,
open fuse, internal control fault, data errors, and blower motor
faults. Data errors are not included in the fault recall list. Diag-
nostic error codes are displayed on a single red LED.
The estimated CFM is displayed on an on-board 7 segment
display. For example, if the CFM is 1240CFM, 7 segment
display shows "FC...A...12...40...".
The DV**PEC air handlers may be used in a fully communi-
cating system when matched with a compatible outdoor unit
and the communicating thermostat. A fully communicating
system offers advanced setup and diagnostic features.
Basic Operation
The air handler control receives operation demand inputs
from the thermostat. The control operates the variable
speed blower motor at the demand as determined from the
thermostat input(s). If a demand for electric heat is received,
the control will provide a 24VAC output for up to two electric
heat sequencers.
Troubleshooting
Motor Control Circuits
WARNING
HIGH VOLTAGE
DISCONNECT ALL POWER BEFORE SERVICING OR
INSTALLING THIS UNIT. MULTIPLE POWER SOURCES
MAY BE PRESENT. FAILURE TO DO SO MAY CAUSE
PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
1. Turn on power to air handler or modular.
WARNING
LINE VOLTAGE NOW PRESENT.
2. Check voltage between pins 1 and 4 at the 4-wire motor
connector on the control board. Voltage should be be-
tween 9 and 15 VDC. Replace control if voltage is not
as specified.
Electric Heat Sequencer Outputs
WARNING
HIGH VOLTAGE
DISCONNECT ALL POWER BEFORE SERVICING OR
INSTALLING THIS UNIT. MULTIPLE POWER SOURC-
ES MAY BE PRESENT. FAILURE TO DO SO MAY
CAUSE PROPERTY DAMAGE, PERSONAL INJURY
OR DEATH.
1. Turn on power to air handler or modular blower.
WARNING
LINE VOLTAGE NOW PRESENT.
2. Disconnect the 3-circuit harness connecting the control
to the electric heater kit.
3. Provide a thermostat demand for low stage auxiliary
heat. Measure the voltage between pins 1 and 3 at the
on-board electric heat connector. Voltage should mea-
sure 24VAC. Replace control if no voltage is present.
NOTE
: Allow for any built-in time delays before making
voltage measurements. Any electric heater faults that are
present may prevent the heater output from energizing. Ver-
ify that no heater faults are present before making voltage
measurements.
Communications
The integrated air handler control has some on-board tools
that may be used to troubleshoot the network. These tools
are: red communications LED, green receive (Rx) LED, and
learn button. These are described below:
a. Red communications LED – Indicates the status of the
network. Refer to the Network Troubleshooting Chart for
the LED status and the corresponding potential problem.
b.
Green receive LED – Indicates network traffic. Refer to
the Network Troubleshooting Chart for the LED status
and the corresponding potential problem.
c. Learn button – Used to reset the network. Depress the
button for approximately 2 seconds to reset the network.
For detail, see NETWORK TROUBLESHOOTING section.
WARNING
LINE VOLTAGE NOW PRESENT.
S-50 CHECKING HEATER LIMIT CONTROL(S)
(OPTIONAL ELECTRIC HEATERS)
Each individual heater element is protected with an auto-
matic rest limit control connected in series with each ele-
