Goodman Mfg RT6100004R13 - Manual (Page 50)

SERVICING
50
1. Remove the wiring from the control terminals.
2. Using an ohmmeter, test for continuity across the nor-
mally closed contacts. No reading indicates the control
is open - replace if necessary.
IF FOUND OPEN - REPLACE - DO NOT WIRE AROUND.
S-61B CHECKING HEATER FUSE LINK
(OPTIONAL ELECTRIC HEATERS)
Each individual heater element is protected with a one time
fuse link which is connected in series with the element. The
fuse link will open at approximately 333°.
WARNING
Disconnect ALL power before servicing.
1. Remove heater element assembly so as to expose fuse
link.
2. Using an ohmmeter, test across the fuse link for continu-
ity - no reading indicates the link is open. Replace as
necessary.
NOTE: The link is designed to open at approximately 333°F.
DO NOT WIRE AROUND - determine reason for failure.
S-62 CHECKING HEATER ELEMENTS
WARNING
Disconnect ALL power before servicing.
1. Disassemble and remove the heating element.
2. Visually inspect the heater assembly for any breaks in
the wire or broken insulators.
3. Using an ohmmeter, test the element for continuity - no
reading indicates the element is open. Replace as
necessary.
S-100 REFRIGERATION REPAIR PRACTICE
DANGER
Always remove the refrigerant charge in a proper
manner before applying heat to the system.
When repairing the refrigeration system:
WARNING
Disconnect ALL power before servicing.
1. Never open a system that is under vacuum. Air and
moisture will be drawn in.
2. Plug or cap all openings.
3. Remove all burrs and clean the brazing surfaces of the
tubing with sand cloth or paper. Brazing materials do not
flow well on oxidized or oily surfaces.
4. Clean the inside of all new tubing to remove oils and pipe
chips.
5. When brazing, sweep the tubing with dry nitrogen to
prevent the formation of oxides on the inside surfaces.
6. Complete any repair by replacing the liquid line drier in the
system, evacuate and charge.
BRAZING MATERIALS
IMPORTANT NOTE: Torch heat required to braze tubes of
various sizes is proportional to the size of the tube. Tubes of
smaller size require less heat to bring the tube to brazing
temperature before adding brazing alloy. Applying too much
heat to any tube can melt the tube. Service personnel must
use the appropriate heat level for the size of the tube being
brazed.
NOTE: The use of a heat shield when brazing is recommended
to avoid burning the serial plate or the finish on the unit. Heat
trap or wet rags should be used to protect heat sensitive
components such as service valves and TXV valves.
Copper to Copper Joints - Sil-Fos used without flux (alloy
of 15% silver, 80% copper, and 5% phosphorous). Recom-
mended heat 1400°F.
Copper to Steel Joints - Silver Solder used without a flux
(alloy of 30% silver, 38% copper, 32% zinc). Recommended
heat - 1200°F.
S-101 LEAK TESTING
(NITROGEN OR NITROGEN-TRACED)
To avoid the risk of fire or explosion, never use
oxygen, high pressure air or flammable gases for leak
testing of a refrigeration system.
WARNING