Gasmaster boilers incorporate a number of safety features. In addition to the commonly used high-temperature cut-off switch, the following sensors are installed as standard features:
A flow switch is installed to monitor the rate of water flow through the system. If this flow rate through the boiler falls below a specified rate of flow, then the flow switch will shut-off the boiler and automatically close the fuel supply valves.
Each Gasmaster unit is equipped with a high-temperature limit switch. If the outlet water temperature exceeds the temperature set-point, which is manually set, the boiler is shut-off and lock-out occurs.
A safety relief valve is installed on the water outlet manifold and supplied as standard equipment. The valve automatically releases the water when the system pressure exceeds the preset limits.
Low Water Cut-Off
A single Low Water Cut-Off sensor and switch is installed on the outlet manifold and monitors the level of water within the piping. It must be reset manually. If for any reason the water level drops below the position of the sensor, the entire system is immediately shut off. A manual reset of the switch is required before the system is once again operational.
Combustion Air Pressure Switch
A single air pressure switch is installed on the blower and measures the air pressure entering the burner. If the combustion air pressure drops by more than 20% below the nominal air pressure (minimum pressure of 0.4″ wc), the burner controller will undergo lock-out and the main gas valves will subsequently and immediately close.
Gas Pressure Switches
One manual reset low gas pressure switch is installed on the gas train in between the gas pressure regulator and the first safety shut off valve. If the line pressure drops below the set-point, the switch will open and the unit will immediately shut down. A second gas pressure switch is also installed on the side of the Riello burner, and should the gas manifold pressure increases above the set-point, the switch will open and the unit will immediately shut down. Additionally, if the exhaust path is at any point clogged, resulting in back pressure generated within the housing, the system will be shut-off.