Daikin DBG Series Service Instructions Manual page 28

SERVICING
DCC:
The Electronic Blower Time Delay Relay is used on PSC
and belt driven models.
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.
Checking EBTDR High Voltage Contacts
1. With power off, remove wires from terminals NC, COM,
and NO.
2. Using a VOM, check for resistance from NO to COM.
Should read open. Next, check for resistance from NC
to COM. Should read closed.
3. If not as above, replace EBTDR.
Checking EBTDR Contact Operation
With power on:
1. Set the thermostat to the fan "on" position.
2. Check for 24 volts at the C and G terminals of the EBTDR.
3. If no voltage present, check fan circuit from thermostat.
If 24 volts present, proceed to step 4.
4. Using A VOM check for 24 volts between the NO termi-
nal on the on the EBTDR and C on the EBTDR board. If
voltage is present go to step 5.
5. With a call for continuous fan from the thermostat using
a VOM check for 24 volts between the COM terminal
EBTDR and C on the EBTDR board. If voltage is present
go to step 6 if not replace the EBTDR.
6. Using a VOM check for 24 volts between the green wire
connection and the blue wire connect ion at the Blower
contactor. If 24 volts is present Replace the contactor.
WARNING
Disconnect ALL power before servicing.
Turn power off.
Testing relay holding coil
1. Remove the leads from the holding coil terminals 1 and
3.
2. Using an ohmmeter, test across the coil terminals 1 and
3. If the coil does not test continuous, replace the relay.
28
Testing relay contacts
WARNING
Disconnect ALL power before servicing.
Turn power off.
1. Using a VOM, test resistance across relay terminals 2
and 4. Should read open.
2. Turn power on.
3. Apply 240 volts to coil terminals 1 and 3.
4. Using a VOM, check for 240 volts from terminals 3 and
1 of relay. Should read 240 volts. In no voltage, check
wiring from heater kit to relay. If voltage present, proceed
to step 5.
5. Using a VOM, check for 240 volts from L1 at contactor
to terminal 4 of relay. Should read 240 volts. Next check
from L1 at contactor to terminal 2 of relay. Should read
240 volts.
If not as above, replace relay.
3. Apply 24 volts to coil terminals 1 and 3.
4. Using a VOM, check for 24 volts from terminals 3 and 2
of relay. Should read 24 volts. If no voltage, check low
voltage wiring from transformer to relay. If voltage present,
proceed to step 5.
5. Using a VOM, check for 24 volts from terminals 3 and 4
of relay. Should read 24 volts.
If not as above, replace relay.