8F" - Backup Heater Outlet Water Temperature Error During Domestic Hot Water Operation; 8H" - Backup Heater Outlet Water Temperature Error; 80" - R4T Entering Water Thermistor Abnormality; 81" - Leaving Water Thermistor R1T Abnormality - Daikin EGSQH10S18AA9W Service Manual

ESIE13-03 | Part 2. Troubleshooting
2.46. "8F" – Backup heater outlet water temperature error during domestic
hot water operation
Trigger
R2T (A1P) detects temperature above
75°C during domestic hot water operation.
Possible cause
Increased water temp by external heat
source.
Faulty thermistor R2T / hydro PCB A1P.
Faulty backup heater contactors (sticking)
K1M, K2M or hydro PCB A1P.
2.47. "8H" – Backup heater outlet water temperature error
Trigger
R2T (A1P) (thermistor after backup
heater) detects temperature above 75°C.
Possible cause
Increased water temp by external heat
source.
Faulty thermistor R2T / hydro PCB A1P.
Faulty backup heater contactors (sticking)
K1M, K2M or hydro PCB A1P.
2.48. "80" – R4T entering water thermistor abnormality
Trigger
Thermistor detects an abnormal value
(open or short circuit).
Possible cause
Faulty entering water thermistor R4T
(A1P) / hydro PCB A1P.
2.49. "81" – Leaving water thermistor R1T abnormality
Trigger
Thermistor detects an abnormal value
(open or short circuit).
Possible cause
Faulty leaving water thermistor R1T /
hydro PCB A1P.
Page 36
Ground source heat pump
Effect
Unit will stop operating.
Check
Check if another heat source is installed
on the same water circuit.
Check thermistor R2T (see page
Check backup heater control contactors
K1M, K2M (see page 54).
Effect
Unit will stop operating.
Check
Check if another heat source is installed
on the same water circuit.
Check thermistor R2T (see page
Check backup heater control contactors
K1M, K2M (see page 54).
Effect
Unit will stop operating.
Check
Check thermistor R4T (see page
Effect
Unit will stop operating.
Check
Check thermistor R1T (see page
2. Error code based troubleshooting
Reset
Via user interface.
Corrective action
Correct hydraulic field circuit. Refer to the
Installer Reference Guide.
58). Replace thermistor R2T (see
hydro PCB A1P (see
Replace the contactor(s) K1M, K2M.
Reset
Via user interface.
Corrective action
Correct hydraulic field circuit. Refer to the
Installer Reference Guide.
58). Replace thermistor R2T (see
hydro PCB A1P (see
Replace the contactor(s) or hydro PCB
A1P (see page 93).
Reset
Auto-reset when problem is solved.
Corrective action
58). Replace thermistor R4T (see
hydro PCB A1P (see
Reset
Auto-reset when problem is solved.
Corrective action
58). Replace thermistor R1T (see
hydro PCB (see page
page 143) or
page 93).
page 143) or
page 93).
page 143) or
page 93).
page 143) or
93).
13/05/15 | Version 2.0