Graco 259079 Operation Manuals page 83

Error Error Type
Code Position
T6AE Heat ALARM
Exchanger
T6BE Heat
Exchanger
T6DA Boost A
T6DB Boost B
T6DE Heat
Exchanger
T6DH Hose
T8AE Heat ALARM
Exchanger
T8BE
3A1705E
Name Cause
RTD Fault A The module is reading
infinite resistance.
RTD Fault B Bad RTD.
RTD Fault A
RTD Fault B
Coolant Outlet
RTD Fault
RTD Cable or FTS Broken RTD cable in
hose or bad FTS.
Fault
Temperature Not No coolant flow
Rising Hx A
Temperature Not Bad valve solenoid.
Rising Hx B
Bad load center.
Troubleshooting
Solution
Check port on module and
wiring to RTD.
Switch the RTD with another
and see if the error message
follows the RTD. Replace
RTD if the error follows the
RTD. See System Repair
manual for instructions.
Expose each hose RTD
connection to check
and retighten any loose
connector. Measure
hose RTD cable and
FTS continuity. See system
repair manual. Order
RTD Test Kit 24N365 for
measurement.
See Temporary Manual
Hose Temperature Control,
page 58, to finish job until
repair can be completed.
Check coolant level. Check
for coolant flow in sight
glass.
Ensure that the circulation
pump has 240 VAC. If not,
replace the circulation pump.
See System Repair manual.
Turn on the manual valve
switch (MV), on the load
center, and see if the valve
solenoid shifts. If not replace
solenoid.
Red, blue, and green LEDs
should light up on load
center board. If not, replace
load center.
83