US Patent 7318735 Standoff heater housing

A circulation heater has a tank with heater tubes located within. The heater tubes are mounted to a header plate, and each contains an electrical resistance heater wire. A standoff plate is mounted to an exterior side of the header plate. Standoff tubes are secured to the standoff plate, each of the standoff tubes registering with one of the heater elements and containing an electrical conductor. A standoff housing is mounted to the opposite ends of the standoff tubes. The electrical conductors in the standoff tubes extend into the standoff housing for connection to electrical power wiring. Detaching the standoff plate from the header plate allows the standoff housing, standoff plate and standoff tubes to be removed as a unit from the tank.