Neglect is an enemy plotting against the life of your fan; lubrication, a few turns of a screw at the proper time, and an automatic timer will increase its life

Keep the (an blade well-tightened on its shaft; continuous operation tends to loosen it.
 
Fans mounted in windows, on floor stands, in attics, etc., for the purpose of keeping air in a house in motion and thus creating a feeling of comfort, must be kept well lubricated and adjusted. Because they turn over at fairly high speeds, sometimes for periods of ten or twelve hours, they must be watched for signs of loosening due to vibration.

Large attic exhaust fans are usually belt driven, and contain two or three set screws that need occasional inspection. The belt itself should be adjusted just like the fan belt of a car: with not more than about an inch of "give" at the center point. Examine the surface of the belt for signs of shredding; this is a sure indication that the pulleys are a little out of line. On practically all belt-driven exhaust fans the motor position is adjustable, and the pulleys can be lined up in a matter of minutes.

Some motors have sealed-for-life bearings.   Most   have   grease   or   oil   fittings.
 
Grease is usually used on the sleeve bearing of the fan blade shaft, and oil on the motor bearings. Small squeeze-tubes of lubricant, which cost only a few cents, are now being sold especially for fan purposes. Don't drown the motor bearings. Read the instruction sheet that came with the fan or the information on the name plate, and take it easy with the oil can. Three or four drops of light machine oil every month or so are usually enough. Too much oil can cause trouble with the internal starting contacts of some types of electric motors.

Extra Protection for Fingers

The guards or grilles fitted to most fans offer very little discouragement to inquisitive children who are attracted by the whirling blades. They'll poke in fingers, pencils, knives and forks, odd pieces of sticks, and anything else that happens to be within reach. Disaster can be discouraged by the addition of ordinary 1/16 mesh metal screening, trimmed to fit all around the existing guard and held in place with little twisted loops of any thin wire. In the case of a window fan, the screening serves the additional purpose of keeping out insects when the machine is not operating. The importance of this feature apparently is overlooked by fan manufacturers.

Diagram shows connections of timer and extra switch which give flexible control of the remote fan; see text.
 
Better Fan Control

Many excellent fans in the larger sizes ... 16 inches and up ... are equipped with automatic timers. These usually are set for any desired numbers of running hours up to 12, after which the motor shuts off by itself. They are designed primarily to operate a fan during the late evening and early morning hours, and to cut it off without requiring the owner to get out of bed to throw a manual switch. However, there are many times when manual control by a hand switch is desirable. This is easily added without    affecting    the    automatic    timer action.   The diagram (above) shows how.

The timer is usually a small electric motor with a pair of contacts. When at the 12 noon or "off" setting, the contacts are open and no current from the power line reaches either the fan motor or the timer motor. When the knob is turned, the contacts close, and both motors start. When the timer motor returns to the starting point, it separates the contacts and the whole system shuts off.

Manual control is provided by a single-pole, double-throw toggle switch. This is widely sold as a "three-way" switch, and is usually used in pairs to control a stair or hall light from either of two positions. This switch does not have an "off" setting. The contact arm, represented by the arrow line 1 in the diagram, touches either contact point 2 or 3. The new connections are very simple. To identify the timer connections without opening the unit, use the Clicktester or the Handitester. The open contacts will, of course, register nothing; the motor will be in the neighborhood of several hundred ohms. No. 1 of the switch goes to one side of the fan; No. 2 to the black or "hot" side of the power line and to the free contact of the timer; No. 3 goes to the common junction of the other contact and one end of the timer motor; the free end of the latter goes to the white or "ground" side of the power line and also to the other side of the fan motor.

Squeeze-tube of lubricant make it a simple matter to   keep   the   blade   bearing   properly   lubricated.

In using  an  oilcan, keep a light thumb—a few drops at a time are enough. Use light machine oil.

An extra screen covering  over a  fan will keep insects  out  and  will  protect  pets  and  children.

Combination automatic-manual control for attic fan has  timer  at  left,  features  a  three-way switch.

If no fan operation is desired, leave the switch handle down. This connects the arm 1 to the terminal 3, but it does not complete the power circuit. To obtain automatic timing, turn the timer knob as usual. This closes the timer contacts and puts current into both the fan and the timer. To turn the fan on for short periods by hand, merely snap the switch up. This sends current to the fan without putting any through the timer. ·

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