Beckett 7600 Boiler User Manual


 
31
AquaSmart Boiler Control Manual
75
50
100
125
150
175
200
225
250
275
300
75
50
100
125
150
175
200
225
250
275
300
How a Boiler Control Works
Figure 19 - Cold Start Operation (Low Limit OFF)
Figure 20 - Warm Start Operation (Low Limit ON) (To maintain domestic hot water temperature)
High Temperature Limit
(Adjustable 100° to 240°F)
Shuts burner off at HIGH LIMIT set point.
High Temperature Differential
(Adjustable 5° to 45°F)
Starts the burner when temperature drops to the
HIGH LIMIT DIFFERENTIAL setting.
Example Shown:
High Limit = 200°
Differential = 20°
During a call for heat, the burner will be
shut off at 200° and be turned back on at
180° (200°-20°). The circulator will
continue to operate until the call for heat
is satis ed.
Low Temperature Limit
(Adjustable 100° to 220°F)
Starts the burner at LOW LIMIT
set point.
Low Temperature Differential
(Adjustable 10° to 45°F)
Shuts burner off when temperature rises to
the LOW LIMIT DIFFERENTIAL setting.
High Temperature Limit
(Adjustable 100° to 240°F)
Shuts burner off at HIGH LIMIT set point.
High Temperature Differential
(Adjustable 5° to 45°F)
Starts the burner when temperature drops to the
HIGH LIMIT DIFFERENTIAL setting.
Example Shown:
Low Limit = 140°
Differential = 10°
During the OFF cycle with no call for
heat, the burner is turned on at 140° to
maintain the boiler water temperature
and is shut off at 150° (140°+10°).
Example Shown:
High Limit = 200°
Differential = 20°
During a call for heat, the burner will be
shut off at 200° and be turned back on at
180° (200°-20°). The circulator will
continue to operate until the call for heat
is satis ed.