Honeywell L8104A Manuel D’Utilisation

Page de 20
11
68-0063—3
L8104A,B,C,D
SETTING AND CHECKOUT  •  OPERATION
TABLE 2—THERMISTOR RESISTANCE AT VARIOUS TEMPERATURES IN CELSIUS.
Operation
L8104A,D
When the temperature at the sensing bulb drops below
the setting on the potentiometer, the relay contacts in the
electronic control module make to open the gas control or
turn on the ignition module. When the temperature rises to
the setpoint, the relay contacts open, closing the gas control
or turning off the ignition module.
The control circuit is accurate to within 
±3.5°F (±1.9°C)
at maximum setpoint. (180
°F (83°C) setpoint controls are
accurate within +7
°F (+3.8°C), -0°F (0°C).
L8104B,C
Operation of the L8104B,C is similar to L8104A,D ex-
cept the electronic control module opens and closes the
relay in response to the average of the temperatures sensed
by the upper and lower sensing bulbs.
ECO LIMIT OPERATION
If the temperature at the ECO switch rises above the
ECO limit setting, the contacts in the ECO switch break and
turn off the water heater.
L8104A,B
The L8104A,B uses a recycling ECO switch that re-
makes once the temperature drops below the ECO tempera-
ture. Before the system will restart, however, the system
must be reset. On a standing pilot system, the pilot must be
relit. On an electronic ignition system, power to the 100
percent lockout ignition module must be off for one minute.
A nonrecycling (one-shot) ECO switch will not remake.
The sensing bulb containing the switch must be replaced.
L8104C,D
The L8104C,D uses a recycling ECO switch. When the
ECO opens, the red LED on the electronic module lights
and the water heater is turned off. To restart the system,
press the black manual reset pushbutton until the red LED
turns off. The ECO switch is closed and the sys-
tem is reset.
Temp-
erature
Resistance (K ohms)
(°C)
0
1
2
3
4
5
6
7
8
9
0
32648
31026
29495
28049
26682
25389
24166
23010
21915
20879
10
19898
18968
18088
17253
16461
15710
14998
14322
13680
13071
20
12492
11942
11419
10922
10450
10000
9572
9165
8778
8409
30
8057
7722
7403
7099
6808
8532
6268
6016
5775
5546
40
5327
5117
4917
4726
4543
4368
4201
4042
3889
3742
50
3602
3468
3340
3217
3099
2986
2878
2774
2675
2579
60
2488
2400
2316
2235
2157
2083
2011
1942
1876
1813
70
1752
1693
1637
1582
1530
1480
1432
1385
1340
1297
80
1256
1216
1177
1140
1105
1070
1037
1005
974
944
90
916
888
861
835
810
786
763
741
719
698