Rheem 199,000 Btu/hr, Руководство пользователя, Страница: 62 / 80

INSTALLATION AND OPERATION INSTRUCTIONS
5-2
TANKLESS WATER HEATER 199
5.2 ELECTRONIC COMPONENTS
This section details the method for troubleshooting the non-standard electronic
components on the unit.
5.2.1 Temperature Sensors
The resistance of the temperature sensors varies inversely with temperature. To
test, measure the temperature of the sensed environment and compare with the
value derived from the measurement of the resistance (obtained by connecting a
good quality test meter capable of measuring up to 5,000 KΩ (5,000,000Ω) at the
controller end of the sensor lead).
To obtain a resistance reading, remove power to the unit. For the water sensors,
remove the wire leads by disconnecting their respective Molex connectors. Place
multi-meter probes into the sensor’s male Molex connector socket. Do not apply
voltage to the sensor as damage may result.
12KΩ temperature sensors are supplied with the unit. See Table 14 for resistance
values.
SENSOR TYPE PURPOSE LOCATION
S0
NTC 12KΩ
Heat Exchanger
Temperature
Left side of Heat Exchanger
S3
NTC 12KΩ
Domestic Hot Water DHW Supply Pipe
S4
NTC 12KΩ
Domestic Cold Water DCW Supply Pipe
S5
NTC 12KΩ
Flue Gas Temperature Top of rear Flue passage
PTC1
PTC2
PTC Cabinet Temperature
Left and right Side top of
inner cabinet
Table 13: Temperature Sensors
5.2.2 Cabinet Sensors
The Cabinet temperature sensors ensure that the unit shuts down if the
temperature inside the cabinet is above normal.
The Cabinet temperature sensors are located on the left and right side at the top
of the cabinet. To remove the sensors, unclip the wiring harness and unscrew
from the top cabinet.
TEMPERATURE RESISTANCE TEMPERATURE RESISTANCE TEMPERATURE RESISTANCE
F / C
Ω - ohm
F / C
Ω - ohm
F / C
Ω - ohm
5F / -15C 76,020 77F / 25C 12,000 149F / 65C 2,752
14F / -10C 58,880 86F / 30C 9,805 158F / 70C 2,337
23F / -5C 45,950 95F / 35C 8,055 167F / 75C 1,994
32F / 0C 36,130 104F / 40C 6,653 176F / 80C 1,707
41F / 5C 28,600 113F / 45C 5,522 185F / 85C 1,467
50F / 10C 22,800 122F / 50C 4,609 194F / 90C 1,266
59F / 15C 18,300 131F / 55C 3,863 203F / 95C 1,096
68F / 20C 14,770 140F / 60C 3,253 212F / 100C 952
Table 14: Temperature Sensor Resistance Values – 12KΩ sensors.
Figure 38: Heat exchanger
Temperature Sensor S0
Cabinet sensors
Figure 39: PTC Cabinet
Temperature Sensors