Description of 1952 Buick Heater and Defroster

The 1952 Buick heater and the defroster are separate units which may be used together or independently as desired. The 1952 Buick underseat heater provides circulation of heated air at floor level. The defroster provides circulation of heated air at shoulder level as well as defrosting of the windshield.

Both units contain water cores which are connected by hoses to the engine cooling system.

The hot water supply is taken from the radiator thermostat housing on the outlet side of engine water pump and is returned to engine cooling system on the inlet side of pump. The volume of hot water flowing through the heater and defroster cores is regulated by a thermostatically actuated temperature control valve mounted on the dash and connected into the water supply line. See figure 11-2.

The 1952 Buick heater is mounted in the floor of body under the right side of front seat. It contains an electric blower which draws air from the body through the hot water core and recirculates the heated air at floor level.

The 1952 Buick defroster is mounted on the right side of cowl under the hood. Outside air is supplied to the defroster by the right hand ventilator duct, which contains an electric blower to provide forced circulation when required. The volume of air passing through the defroster core is controlled by a fly valve inside the defroster housing which is connected by a wire to the control knob on instrument panel. The heated outside air then flows through ducts to openings along the base of windshield where it moves upward against the windshield, which deflects the flow rearward into the body at shoulder level.

1952 Buick Heater and Defroster Controls

The 1952 Buick heater blower is controlled by a “HEATER” switch mounted on the radio speaker grille. When heater switch knob is turned fully counterclockwise the blower is turned off. Turning knob clockwise, the first step gives high speed blower operation and the second step gives low speed operation.

The 1952 Buick defroster blower switch and the air valve control are combined in one unit mounted on the radio speaker grille. Pulling out the “DEFROSTER” knob opens the air valve and turning the knob clockwise turns on the defroster blower. The defroster blower has only one speed.

The heater temperature control is manually set to the desired body air temperature by moving the “HEATER CONTROL” lever located below the radio speaker grille. The control lever has four marked positions: “OFF”, “LOW”, “NORMAL”, and “HIGH”, which are self-explanatory. Once set for a desired body temperature the temperature control unit will automatically maintain this temperature without further adjustment of the control lever.

When the car is cold the temperature control valve stands open to permit maximum flow of water through the heater and defroster cores. As the body air temperature comes up to the level for which the temperature control is set the valve operates to reduce the water flow and maintain the desired air temperature. Since the air temperature will come up to the level as rapidly as existing water temperature will permit it is unnecessary and undesirable to attempt quick warm-up by manipulating the temperature control lever.

When 1952 Buick heating system is in operation a front door ventilator should be opened about %” to let out old air. The opened ventilator should be on opposite side from which wind may be blowing.

Hot water flow through the heater and defroster cores is completely shut off when the temperature control lever is in the “OFF” position. This shuts off all heat when not desired, such as for summer driving. This feature eliminates the need for a shut-off valve in water line at engine.

On Series 40, the control valve for the right hand outside air ventilator is mounted in the defroster housing and ventilator air flows through the defroster core. When it is desirable to warm the incoming air, the temperature control lever may be set at one of the “open” positions. When maximum cooling is desired, however, it is important to set the temperature control lever in the “OFF” position to shut off hot water circulation through the defroster core.

NOTE: To keep out offensive traffic odors and exhaust gases when traveling in congested traffic or when parked behind a car having its engine running, all ventilator and defroster control knobs must be pushed forward to close the valves, and the defroster blower must be turned off.


Avoid inhaling exhaust gases when any concentration of these is present in the air, i.e., in a garage, in congested traffic, or when stopped closely behind a vehicle with its motor running. Exhaust gases may have strong odors which normally should give warning of their presence. However, the exhaust gases from some vehicles may not be noticeable under certain conditions and the senses of people react differently. Exhaust gases contain a percentage of carbon monoxide which is a poisonous gas that, by itself, is tasteless, colorless, and odorless.

Temperature Control Lever Adjustment

The 1952 Buick temperature control valve is operated by a lever through a sheathed operating wire. To insure full range of temperature control, the valve must act as the stop at both ends of lever travel. Since the operating wire is of fixed length with loops at each end, full range of operation is obtained by clamping the operating wire sheath in proper location on the control lever support and the temperature control assembly, as follows:

  1. Connect operating wire to control lever and clamp end of sheath flush with edge of clamp on the lever support. Center the control lever under the “0” at “OFF” position, approximately two notches from the end of the lever travel.
  2. Turn temperature control valve all the way clockwise until the cam locks against the roller. This is the extreme “off” position. Connect operating wire to brass post on valve and clamp the sheath to valve assembly. See figure 11-1.
    1952 Buick Temperature Control Lever Adjustment

    1952 Buick Temperature Control Lever Adjustment

  3. Operate the control lever through full range to make certain that the valve provides the stop at both ends.

1952 Buick Heater and Defroster Wiring and Hose Connections

The 1952 Buick heater and defroster blower motors are supplied with current from the “Accessories” terminal of the ignition switch. The supply wire extends from the ignition switch to the fuse block under the cowl where a fuse is located to protect the circuit. Wires from the fuse block connect to the 1952 Buick heater and defroster switches and from the switches to the motors. See 1952 Buick chassis wiring circuit diagrams in Section 10-J.