Harman PB 105 - Page 25

25
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Pellet Boiler Outdoor Air Reset Operation
When the outdoor sensor is installed, at 20° F. or below OAT (Outdoor Air Temperature), the boiler will operate at the temperature set on the Maximum Temperature knob. The boiler water temperature will decrease by 1 degree for every 1 degree in temperature rise of the Outside Air. Example 1 OAT Water Temp Degree Change Max set at 185
o
65
o
140
o
-45°
Min set at 140
o
60
o
145
o
-40°
55
o
150
o
-35°
50
o
155
o
-30°
45
o
160
o
-25
o
40
o
165
o
-20
o
35
o
170
o
-15
o
30
o
175
o
-10
o
25
o
180
o
-5
o
20
o
185
o
0
o
15
o
185
o
0
o
10
o
185
o
0
o
5
o
185
o
0°
0
o
185
o
Example 2 OAT Water Temp Degree Change Max set at 180
o
65
o
150
o
*
Min set at 150
o
60
o
150
o
*
55
o
150
o
*
50
o
150
o
-30
o
45
o
155
o
-25
o
40
o
160
o
-20
o
35
o
165
o
-15
o
30
o
170
o
-10
o
25
o
175
o
-5
o
20
o
180
o
0
o
15
o
180
o
0
o
10
o
180
o
0
o
5
o
180
o
0
o
0
o
180
o
0
o
* No change in boiler temperature after reaching minimum setpoint temperature.