Ti Series Installation and Operation Instructions
│
Trinity
45
Reset Curve for Res=85 & Setpoint=160
70
90
110
130
150
170
-10
0
10
20
30
40
50
60
70
80
90
100
Outdoor Temperature (deg.F)
W
a
te
r
T
e
m
p
. (
F
)
Outdoor Sensor (10K)
To fully take advantage of the energy saving features of the Trinity boiler, it is necessary to install the outdoor sensor provided.
Install the sensor preferably on the north, or coldest side of the building, not within 10 feet of the discharge of the gas vent outlet,
or other sources of heat. The outdoor sensor connects to the top of the boiler on terminals O and D.
Calculating Outdoor Reset Curve (RES)
Table 12-4
Low Voltage Field Connections
Boiler Set Point – HI
Outdoor Reset – RES
80 – 110
70 – 80
110 – 140
80 – 90
140 – 170
90 – 100
170 – 200
100 – 110
Formula:
Operating Temperature (HI
CALC.
) = {(RES – Outdoor Temp) x (HI – RES) / RES} + RES
Example:
There is a call for heat and no call for domestic hot water (T-C closed & A-C open), the control
uses the programmed HI and RES settings and the current outdoor temperature.
The HI is programmed to be 160°F.
The RES is programmed to be 85°F.
The outdoor temperature is 40°F.
Operating Temperature = {(85 – 40) x (160 – 85) / 85} + 85 =
125°F
The following chart illustrates the effect of changing outdoor temperature on the boiler operating temperature for
the above example.
