A.O. Smith T-H2-DV User Manual

T-H2-DV/T-H2-OS Service Manual
Ver. 1.01
70
CONFIDENTIAL
12-7. (B) ON/OFF conditions: BTU requirements
A. Calculating the ON/OFF conditions of the T-H2-DV or T-H2-OS
【Condition needed to turn the T-H2-DV or T-H2-OS ON】
 ( T
set
– T
in
) × GPM × 500 > 14,880
【Condition needed to turn the T-H2-DV or T-H2-OS OFF】
( T
set
– T
in
) × GPM × 500 < 11,900 or T
in
= T
set
Where: T
set
= Set temperature and T
in
= Inlet temperature
B. Calculation example
Set temperature: T
set
= 120˚F    Flow rate = 2.5 GPM
【Condition needed to turn the T-H2-DV or T-H2-OS ON】
(120 – T
in
) × 2.5 × 500 > 14,880 T
in
< 108.1˚F
【Condition needed to turn the T-H2-DV or T-H2-OS OFF】
(120 – T
in
) × 2.5 × 500 < 11,900 T
in
> 110.5 ˚F
The output temperature at that moment will be 120˚F
C. ON/OFF table
Set temperature
(˚F)
Flow rate (GPM)
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
100
ON 40.5 70.2 80.2 85.1 88.1 90.1 91.5 92.6
OFF 52.4 76.2 84.1 88.1 90.5 92.1 93.2 94.0
115
ON 55.5 85.2 95.2 100.1 103.1 105.1 106.5 107.6
OFF 67.4 91.2 99.1 103.1 105.5 107.1 108.2 109.0
120
ON 60.5 90.2 100.2 105.1 108.1 110.1 111.5 112.6
OFF 72.4 96.2 104.1 108.1 110.5 112.1 113.2 114.0
135
ON 75.5 105.2 115.2 120.1 123.1 125.1 126.5 127.6
OFF 87.4 111.2 119.1 123.1 125.5 127.1 128.2 129.0
145
ON 85.5 115.2 125.2 130.1 133.1 135.1 136.5 137.6
OFF 97.4 121.2 129.1 133.1 135.5 137.1 138.2 139.0
155
ON 95.5 125.2 135.2 140.1 143.1 145.1 146.5 147.6
OFF 107.4 131.2 139.1 143.1 145.5 147.1 148.2 149.0
165
ON 105.5 135.2 145.2 150.1 153.1 155.1 156.5 157.6
OFF 117.4 141.2 149.1 153.1 155.5 157.1 158.2 159.0
185
ON 125.5 155.2 165.2 170.1 173.1 175.1 176.5 177.6
OFF 137.4 161.2 169.1 173.1 175.5 177.1 178.2 179.0

A.O. Smith T-H2-DV Specifications

General

Brand	A.O. Smith
Model	T-H2-DV
Category	Water Heater
Language	English