Inventors:
James Fuller - Zionsville IN, US
David M. Stedham - Reno NV, US
Assignee:
Wessels Company - Greenwood IN
International Classification:
G08B 21/00
Abstract:
An expansion tank which comprises a tank having a predetermined volume capacity; a flexible diaphragm in the tank, partitioning tank volume into a liquid-containing portion for holding liquid and a gas-containing portion for holding a gas under a pressure that defines a normal pressurized gas volume when the liquid-containing portion holds a predetermined liquid volume; and a proximity sensor suspended in the gas-containing portion of the tank and adapted to energize an alarm signal when volume of the gas-containing portion is reduced a predetermined amount as indicated by proximity of the diaphragm.