Maintenance; Precautions Before Maintenance - Lennox LI012CO-230P432 Service Manual

9. Maintenance

9.1 Precautions before Maintenance

There are high-capacity electrolytic capacitors on the outdoor mainboard. Thus, even the power is cut off, there is high voltage inside
the capacitors and it needs more than 20min to reduce the voltage to safety value. Touching the electrolytic capacitor within 20min after
cutting the power will cause electric shock. If maintenance is needed, follow the steps below to discharge electricity of electrolytic ca-
pacitor after power off.
(1) Open the top cover of outdoor unit and then remove the cover of electric box.
(2) As shown in the fig below, connect the plug of discharge resistance (about 100ohm, 20W) (if there is no discharge resistance, you
can use the plug of soldering iron) to point A and B of electrolytic capacitor. There will be sparks when touching them. Press them forc-
ibly for 30s to discharge electricity of electrolytic capacitor.
outdoor mainboard
(3) After finish discharging electricity, measure the voltage between point A and B with universal meter to make sure if electricity dis-
charging is completed, in order to prevent electric shock. If the voltage between the two points is below 20V, you can perform mainte-
nance safely.
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cover of electric box
discharge resistance or
plug of soldering iron
B
A
B
A
Service Manual
outdoor mainboard
Installation and Maintenance