Safety And Operating Controls; Table 15: Safety And Operating Controls - Thermal Solutions Arctic Installation & Operation Manual

Arctic Installation and Operation Manual
5.6

Safety and Operating Controls

All of the safety control devices listed in Table 15 are logically linked to the Concert Boiler Control
that supervises the sequence of operation of the boiler for safe and efficient operation. It does so by
ensuring proper light off and firing of the main burner and if need be, will immediately cut-off gas
supply to the main burner when gas pressure, water temperature, water flow or another critical
attribute is outside of the operational settings. It also varies the combustion rate in real time to meet
the desired load of the system.
Do not install, operate, service or repair any components of this equipment unless you are
qualified and fully understand all requirements and procedures. Trained personnel should
refer to those who have completed Thermal Solutions Service School training specific to this
product.
Component
If this switch is in the off position, power is interrupted to the control circuit of the boiler,
Power
which prevents the boiler from operating. If the switch is in the on position, power is
Switch
supplied to the control circuit.
Automatic
If the boiler water temperature exceeds the adjustable set point, power is interrupted to the
Reset
control circuit of the boiler, which prevents the boiler from operating. When the boiler water
temperature drops below the set point minus the adjustable differential setting, power is again
Operating
supplied to the control circuit.
Aquastat
If the boiler water temperature exceeds the adjustable set point, power is interrupted to the
Manual
control circuit of the boiler, which prevents the boiler from operating. Power is interrupted
Reset High
until the control is manually reset pressing the control's reset button. When the button is
Limit
pressed, power will again be supplied to the control circuit, assuming that the boiler water
Aquastat
temperature has dropped below the setpoint minus the differential setting.
If the water flow through the boiler drops below the fixed flow rate required to move the
Water Flow control's paddle enough to close the control's contacts, power is interrupted to the control
Switch circuit, which prevents the boiler from operating. When the water flow rate increased, the
paddle closes the control's contacts and power is supplied to the control circuit.
Pressure /
If the pressure inside the boiler exceeds the fixed set point, the valve opens mechanically and
Safety
discharges water. The valve remains open until the pressure inside the boiler drops below the
set point.
Relief Valve
If the gas pressure reaches a point above or below the adjustable set point, the contacts of
High and
the switch open and power is interrupted to the control circuit that prevents the boiler from
Low Gas
operating. Power is interrupted until gas pressure is between the high and low gas pressure
Pressure
set points and the control is manually reset moving the switch to the reset position. The
Switches
switches will not reset until the gas pressure is within the set point parameters.
Minimum
If the differential air pressure drops below the fixed set point, the contacts of the switch open
Air
and power is interrupted to the control circuit, which prevents the boiler from operating.
Pressure
Power is interrupted until air flow/pressure increases so that contacts close.
Switch
Thermal Solutions, 1175 Manheim Pike, Lancaster, PA 17601 Web:
Phone: 717-239-7642 Fax: 877-501-5212 Email:
38
WARNING

Table 15: Safety and Operating Controls

Function
www.thermalsolutions.com
sales@thermalsolutions.com
Form: 2435
Revision: 8
Date: 9-19-2016