T-D2-IN / T-D2-OS Service Manual
Ver. 1.00
57
CONFIDENTIAL
12-7.(B) ON/OFF conditions: BTU requirements
A. Calculating the ON/OFF conditions of the T-D2-IN or T-D2-OS
【
Condition needed to turn the T-D2-IN or T-D2-OS ON
】
( T
set
– T
in
) × GPM × 500 > 14,880
【
Condition needed to turn the T-D2-IN or T-D2-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
= 122
˚
F
Flow rate = 2.5 GPM
【
Condition needed to turn the T-D2-IN or T-D2-OS ON
】
(122 – T
in
) × 2.5 × 500 > 14,880 T
in
< 110.1
˚
F
【
Condition needed to turn the T-D2-IN or T-D2-OS OFF
】
(122 – T
in
) × 2.5 × 500 < 11,900 T
in
> 112.5
˚
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
113
ON
53.5
83.2
93.2
98.1
101.1
103.1
104.5
105.6
OFF
65.4
89.2
97.1
101.1
103.5
105.1
106.2
107.0
122
ON
62.5
92.2
102.2
107.1
110.1
112.1
113.5
114.6
OFF
74.4
98.2
106.1
110.1
112.5
114.1
115.2
116.0
131
ON
71.5
101.2
111.2
116.1
119.1
121.1
122.5
123.6
OFF
83.4
107.2
115.1
119.1
121.5
123.1
124.2
125.0
140
ON
80.5
110.2
120.2
125.1
128.1
130.1
131.5
132.6
OFF
92.4
116.2
124.1
128.1
130.5
132.1
133.2
134.0
158
ON
98.5
128.2
138.2
143.1
146.1
148.1
149.5
150.6
OFF
110.4
134.2
142.1
146.1
148.5
150.1
151.2
152.0
167
ON
107.5
137.2
147.2
152.1
155.1
157.1
158.5
159.6
OFF
119.4
143.2
151.1
155.1
157.5
159.1
160.2
161.0
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
