A.O. Smith 240 T-H3J Service Manual page 73

12-9. Multi-unit system ON/OFF conditions
Only 540 (T-H3) models
RATE and the SET TEMPERATURE.
Flow rate required to activate additional 540 (T-H3) models = A × n
Where n
and A is dependent on the set temperature. See table below:
Set temperature
°F
100 - 120
125 - 130
135 - 140
145
150 - 185
A. In the case of reducing down from two units of 540 (T-H3) models to one unit of 540
Flow rate = A / 1.7
B.
To activate additional
540 (T-H3) models
Unit No.
No.1 ON
No.2 ON
No.3 ON
No.4 ON
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
°C
38 - 49
52 - 54
57 - 60
63
66 - 85
Factor "A"
GPM L / min
0.5 1.9
3.4 13
6.8 26
10.2 39
73
Factor "A"
GPM
3.4 13
3.2 12
2.9 11
2.6 10
2.4 9
To reduce number of activated
540 (T-H3) models
Unit No.
GPM
No.4 ON 6.8
No.3 ON 3.4
No.2 ON 2.0
No.1 ON 0.37
Page
CONFIDENTIAL
Ver. 1.00
FLOW
Factor "A"
L / min
26
13
7.6
1.5