Abstract: A water heater is provided for connection to a heated fluid source for transfer of heat from the heated fluid to water in the water heater. The water heater includes a shell having a water storage tank and a heat exchange chamber mounted within the tank. The water heater also has an inlet tube and outlet tube for the introduction and removal of water from the tank. A supply line is connected to the heat exchange chamber to introduce heated fluid into the chamber. A return line, also connected to the heat exchange chamber, removes fluid for reheating. Water stored in the tank is heated by heat exchange from heated fluid recirculated through the heat exchange chamber.

Abstract: A control system for a gas water heater including a fuel rate control valve, a water flow switch to control the fuel rate valve, an inlet water temperature switch to reduce fuel flow when inlet temperature is high, a temperature switch at the water outlet to shut off fuel at a high temperature and a temperature sensor at the water outlet to regulate the fuel valve.

Abstract: A water heater having an insulated water tank with a cold water inlet line, a hot water outlet line and a baffled flue pipe extending vertically through the tank is provided. The flue pipe extends from a combustion chamber housing a burner located beneath the tank, to a flue gas collection chamber positioned above the tank. The collection chamber is in fluid communicatioon with a blower and a flue gas exhaust line for conveying the flue gases through the exhaust line to a direct through-the-wall vent. Control apparatus is provided for sensing the temperature of the water in the tank and controlling the amount of fuel supplied to the burner in response thereto. The control apparatus turns on the blower when fuel is being supplied to the burner and turns off the blower when no fuel is being supplied to the burner.

Abstract: A water heater having an insulated water tank with a cold water inlet line, a hot water outlet line and a baffled flue pipe extending vertically through the tank is provided. The flue pipe extends from a combustion chamber housing a burner located beneath the tank, to a flue gas collection chamber positioned above the tank. The collection chamber is in fluid communication with a blower and a flue gas exhaust line for conveying the flue gases through the exhaust line to a direct through-the-wall vent. Control apparatus is provided for sensing the temperature of the water in the tank and controlling the amount of fuel supplied to the burner in response thereto. The control apparatus turns on the blower when fuel is being supplied to the burner and turns off the blower when no fuel is being supplied to the burner.

Abstract: Apparatus and method for a circuit which is connected in series between the call signal output of a vehicle detector and the call signal input of a traffic controller is disclosed. Under normal operating conditions the invention acts as a signal buffer and input of the invention will be applied to the input of the traffic controller when call signal inputs are continuously present or not present for preestablished times, then test procedures are implemented. During a test or failure condition of the vehicle detector, the detector output signal will be disconnected from the controller. The invention also provides a circuit which is connected between the loop and the loop input of the vehicle detector. The circuit along with the accompanying method is designed to modify the input impedance to the vehicle detector to apply a test or "forced" call signal to the vehicle detector input when a call signal input is not received after a predetermined period of time, a fault condition is established.

Abstract: Dual flow circuitry is utilized to transport fluid held in a tank through a heating means by providing means for carrying both inflow and outflow streams and means for depositing the inflowing stream at a predetermined level in the tank while utilizing only one tank opening. The dual flow circuitry can be used to supplement an ordinary residential or other hot water heating system with a heat pump.

Abstract: A recorder of the states of a traffic control system which stores and visually displays the current operational state of the system. The current states of the command signals produced by the traffic controller of the system and the current states of energization of each traffic signal light, after a predetermined delay, are stored in a bistable device. The occurrence of an error, conflicting or improper timing of the energization of the traffic lights of the system or of the command signals controlling the energization of such lights are sensed by a conflict monitor. Upon the occurrence of an error, the bistable devices are latched, i.e. prevented from thereafter changing state. The state of each bistable device is visually displayed as of the occurrence of an error.

Abstract: A water heater having an insulated water tank with a cold water inlet line, a hot water outlet line and a baffled flue pipe extending vertically through the tank is provided. The flue pipe extends from a combustion chamber housing a burner located beneath the tank, to a flue gas collection chamber positioned above the tank. The collection chamber is in fluid communication with a blower and a flue gas exhaust line for conveying the flue gases through the exhaust line to a direct through-the-wall vent. Control apparatus is provided for sensing the temperature of the water in the tank and controlling the amount of fuel supplied to the burner in response thereto. The control apparatus turns on the blower when fuel is being supplied to the burner and turns off the blower when no fuel is being supplied to the burner.