Method and apparatus for testing low water fuel cut-off switches

Claim 2

In a controller unit for inspecting the operation of hot water boiler systems, a plurality of means comprising sensing means responsive to a low water level in a boiler to provide an indicating signal, upper and lower equalizing pipes connecting upper and lower parts of said sensing means to a boiler, first flow restricting means including a velocity check valve positioned in said upper equalizing pipe, second flow restricting means including a velocity check valve positioned in said lower equalizing pipe, a vacuum breaker connected to the upper equalizing pipe between the sensing means and the first flow restricting means, and draining means including a drain valve connected to the lower equalizing pipe between the sensing means and the second flow restricting means, whereby the sensing means may be inspected by opening the draining means and observing the reaction in the system.

Claim 3

A unit as claimed in claim 1, in which the sensing means includes a low water fuel cut-off switch.

Claim 4

A unit as claimed in claim 1, in which said velocity check valves are spring loaded to be normally open to permit easy clean-out by rodding of the associated equalizing pipes.

Claim 5

A unit as claimed in claim 1, in which said velocity check valves incorporate openings to permit establishment of pressure equalization when the draining means is closed.

Claim 6

A unit as claimed in claim 1, in which the velocity check valves include means permitting pressure to be equalized in said equalizing pipes when the draining means are closed, and the velocity check valves include spring means to restore the valves to an open position when the pressure is equalized.

Claim 7

A unit as claimed in claim 1, in which said velocity check valves are spring loaded to be normally open to permit easy clean-out by rodding of the associated equalizing pipes, and said velocity check valves include openings permitting restoration of equal pressure on opposite sides of the valves, enabling them to return to the normally open position after closing.

Claim 8

Apparatus as claimed in claim 1, in which the sensing means responsive to a low water level includes a float movable in a float chamber to activate signal means in response to a drop in water level in the boiler below a certain level, and said velocity check valves operate to close and limit flow to said float chamber in response to flow induced by opening said draining means.

Claim 9

Apparatus as claimed in claim 1, in which the sensing means responsive to a low water level includes a float movable in a float chamber to activate signal means in response to a drop in water level in the boiler below a certain level, said velocity check valves operate to close and limit flow to said float chamber in response to flow induced by opening said draining means, and said vacuum breaker releases fluid in said float chamber to permit said float to drop and activate the signal means.

Claim 10

Apparatus for inspecting the operation of a low water fuel cut-off switch in a hot water boiler system, in which the low water fuel cut-off switch includes a float movable in a float chamber to activate signal means in response to a drop in water level in the boiler below a certain level, comprising upper and lower equalizing pipes connecting respective upper and lower parts of a low water fuel cut-off switch to a boiler, first flow restricting means in said upper equalizing pipe, second flow restricting means in said lower equalizing pipe, the first and second flow restricting means including velocity check valves, said velocity check valves operating to close and limit flow to a float chamber in response to flow induced by opening said draining means, and said vacuum breaker releasing fluid in said float Chamber to permit said float to drop and activate the signal means, a vacuum breaker connected to the upper equalizing pipe between the switch and the first flow restricting means, and draining means connected to the lower equalizing pipe between the sensing means and the second flow restricting means, whereby the operation of the switch may be inspected by operating the draining means and observing the reaction of the system.

Claim 11

Apparatus for inspecting the operation of a low water fuel cut-off switch in a hot water boiler system, in which the low water fuel cut-off switch includes a float movable in a float chamber to activate signal means in response to a drop in water level in the boiler below a certain level, comprising upper and lower equalizing pipes connecting respective upper and lower parts of a low water fuel cut-off switch to a boiler, first flow restricting means in said upper equalizing pipe, second flow restricting means in said lower equalizing pipe, the first and second flow restricting means including velocity check valves, said velocity check valves operating to close and limit flow to a float chamber in response to flow induced by opening said draining means, and said vacuum breaker releasing fluid in said float Chamber to permit said float to drop and activate the signal means, a vacuum breaker connected to the upper equalizing pipe between the switch and the first flow restricting means, and draining means connected to the lower equalizing pipe between the sensing means and the second flow restricting means, whereby the operation of the switch may be inspected by operating the draining means and observing the reaction of the system.