"WASHED, IRONED AND STARCHED"

New Zealand Listener, Volume 5, Issue 121, 17 October 1941, Unnumbered Page

"WASHED, IRONED AND STARCHED"

How IZB’s Air Conditioning Works

of 1ZB is a space which the prying visitor would be pardoned for mistaking for the boiler room of a ferry boat. To one side, as you enter, is a huge bulbous cylinder, about 30 feet long and 12 feet high; facing you is a frightening bank of electric switches, fuses and buttons marked "Stop" and "Start"; to the right are several iron boxes with glass windows which distantly resemble incubators; and from these lead square galvanised iron pipes which distantly resemble huge parcel chutes. It is a bewildering place, and although the electric motors make no noise or vibration, you come away with the impression that a lot of work is done there. It houses, in fact, the machinery which atténds to the air conditioning and heating of the new 1ZB building. These systems-there are two, one for the studios, one for the radio theatreare as complete, the people who designed them claim, as it is possible to make them. A descripition of how they work would involve an expedition into the highfalutin’ terminology of the air-condition-ing expert, which is scattered with words like "humidifier"? ‘"hygrostat" and "thermostat." Perhaps it is most simply explained by stating that the air in the 1ZB studios and radio theatre is kept at a constant temperature of about 65 degrees to 70 degrees in summer, and about 65 degrees in winter, and at a constant humidity, summer and winter, down in the "Zpnards"

of about 50 per cent.; and that when the temperature or relative humidity shows signs of varying from _ these figures, thermostatic control automatically brings the air-conditioning plant into operation and adjusts it in a jiffy. All air which enters the studios and theatre is first of all sucked down a shaft which has its outlet away up in the roof of the building. Once arrived in the basement, it is "washed, ironed and starched " as the air-conditioning experts jocularly put it, and passed through the ceilings, the stale air being withdrawn through vents near the floor. The washing, ironing and starching involves passing the air through oil filters (which extract a. surprising amount of debris from Auckland’s atmosphere, by the way); then, in summer, dehumidifying it by cooling to a lower temperature than necessary and re-heating, or, in winter, humidifying by passing it through a fine mist of water; and finally bringing it to the correct temperature and forwarding it on by means of big electric fans. A Lot Of Refrigeration The refrigerating engine, which will be kept pretty busy during an average Auckland summer, represents about 15 tons of refrigeration, or enough to run more than 100 medium-sized kitchen refrigerators. The bulbous boiler, used for heating 1ZB’s offices and the offices of the other Government departments in the building, has an internal diameter of 10 feet, an internal length of 26 feet 6 inches, and contains 11,500 gallons of water which expands by 500 gallons when heated by an element of 390 kilowatsthe average household heating element is approximately one kilowat.