Abstract: A heater for fluids including a housing made of a non-metallic material and having an internal cavity. The housing has an inlet and an outlet, each of which are in fluid communication with the internal cavity. An elongated electrical heating element is disposed within the cavity for heating fluid flowing through the cavity. The heating element has a generally circular cross-sectional shape and has a U-shaped portion disposed in the cavity. The electrical heating element has electrical connectors at opposite ends extending through the housing. The electrical heating element has a titanium outer surface.

Abstract: An electrical heater for fluid including a generally tubular housing have a wall portion made of a titanium material, and an elongated electrical heating element having electrical connectors on opposite ends thereof extending through the wall portion. The electrical heating element has an outer sheath made of a titanium material, and an inner sheath made of a stainless steel material. The electrical heating element has an electrical resistance line disposed within the inner sheath and connected to the electrical connectors at opposite ends thereof. The electrical heating element includes a dielectric material disposed within the inner sheath around the electrical resistance line to facilitate heat transfer from the electrical resistance line to the inner sheath.

Abstract: A fitting for connecting to an end of tubing. The fitting includes a fitting body having a generally tubular construction with a first end adapted for leakproof connection to another component. A second end has a socket connector with tapered interior sidewall portions forming a truncated conical shape such that an end of a tube can be inserted into the socket connector and tightly wedged therein to form a leakproof seal. At least a portion of the fitting body is made of a light-transmitting material such that material lodged within the fitting body is visible from the exterior of the fitting body.

Abstract: A spa system includes a tub, a pump, an electrical heater, and a tubing system interconnecting the tub, pump, and electric heater to provide recirculating flow of water through the spa system. The electrical heater includes a housing made of a polymer material and defining an internal passageway adapted for fluid flow through the housing. The housing has a first opening in fluid communication with the passageway, and a pair of access openings. The housing further includes a second opening in fluid communication with the tubing system. The heater also includes a heater tube defining a first end connected to the first opening in the housing. An elongated electrical heating element is at least partly disposed within the outer tube, and has opposite ends extending out of the first end of the heater tube and through the pair of access openings. The electrical heater includes compressions fittings sealingly connecting the heater tube and the elongated heating element to the housing.

Abstract: A pressure switch is provided for opening and closing an electrical switch based on a pressure set point. The pressure switch includes a housing having walls defining a fluid chamber adapted to receive a fluid. The pressure switch also includes a snap disc having a front surface in pressure communication with the fluid chamber and responsive to switch states between first and second shapes. The pressure switch further includes a circuit board having printed circuitry and first and second electrical terminals. The snap disc has a rear conductive surface that forms a closed circuit between the first and second terminals when in the first shape and forms an open circuit when in the second shape.

Abstract: A heater having a shut off device is provided which prevents false over temperature lockouts. The heater comprises a body having walls defining a volume for holding water, a heating element thermally coupled to the body for heating water within the body, and a temperature sensor for sensing temperature of the material. The heater also has a shut off switch for shutting off electric current in the heater when the sensed temperature of the water exceeds a predetermined maximum temperature limit, and a manually actuated reset input for resetting the shut off switch to allow current to be applied to the heater. The heater further includes a controller coupled to the shut off switch and the reset switch, wherein the controller determines the presence of a false over temperature event and overrides the need to manually actuate the reset input.

Abstract: A fitting for connecting to an end of tubing. The fitting includes a fitting body having a generally tubular construction with a first end adapted for leakproof connection to another component. A second end has a socket connector with tapered interior sidewall portions forming a truncated conical shape such that an end of a tube can be inserted into the socket connector and tightly wedged therein to form a leakproof seal. At least a portion of the fitting body is made of a light-transmitting material such that material lodged within the fitting body is visible from the exterior of the fitting body.

Abstract: An electric water heater is provided which includes a polymeric body having an elongated hollow and an inlet opening and an outlet opening in communication with the hollow for flowing water to pass therethrough. An electrical resistance heater having a heating element of a material exhibiting a positive temperature coefficient of resistance is disposed in the hollow of the polymeric body and in heat transfer communication with water flowing through the hollow. An electrical source supplies electrical power to the heating element to generate heat. A controller senses current flow through the heating element and determines a resistance related value, such as current or resistance of the heating element. The controller also determines a first derivative of the resistance related value over time, and determines a second derivative of the resistance related value over time, and controls power supply to the heating element as a function of the first and second derivatives and/or absolute resistance.

Abstract: A pulsed shaker shocker is provided in which an intermittent pulsed action is provided to the containers carrying liquid to enhance the shaking action for the liquid carried in the containers. Such shaking action is found for separatory type shakers, and the pulsed action enables a more efficient shaking action to be obtained. The pulsed nature of the shaker shocker more closely resembles the manual shaking action, and this way, more efficient shaking may be obtained.