From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Letter from Harrison Radiator Corporation concerning defrosters, car heaters, and vehicle air infiltration.
| Identifier | ExFiles\Box 149a\3\ scan0202 | |
| Date | 12th April 1936 | |
| HARRISON RADIATOR CORPORATION LOCKPORT, NEW YORK Mr. C. S. Steadman, Page 2. 12/4/36. purposes only. Regarding defrosters, we are mounting a separate blower on top of the heater which draws air from the heated side of the core so that with the front doors of the heater closed, the hot air runs through the small blower and is directed to the windshield via suitably arranged pipes and a discharge nozzle. Am enclosing instruction sheets which are sent out with our heater packages. Approximately 20 to 25 cu.ft. of air per minute are handled by the defroster motor. Concerning car heaters, one point which has been sadly overlooked over here has been the fact that regardless of the water temperature, if the heater itself does not have sufficient surface to provide an adequate amount of heat, regardless of the temperature of the water, the car will not be adequately heated. We have found that water circulated through the heater proper in excess of 3 gallons per minute (American gallons) does not increase the heat output from the unit, the limiting factor being the air supply. During some Research Work which was conducted some years ago on air conditioning of automobiles, from an investigation point of view only, we found that body leakage was a very vital factor, the body leakage of course, being equally important from the heating point of view. We measured the body leakage by placing in the rear window frame, a piece of sheet material to which was connected a duct leading to the intake side of an exhaust fan, then maintaining a given depression in the body, the volume of air handled by the fan was measured. In this manner, the most prolific source of leaks could be readily discovered and means taken to correct the air infiltration. Without exception, the greatest source of air infiltration was found to be under the rear cushion and of course, around the doors, windows, windshield, etc. By placing someone in the car while this test is in operation, the worst drafts can be readily discovered. As a matter of interest we found one car of the very low production variety which at a depression of 1/2" of water actually leaked 660 cu.ft. of air a minute. Am passing this information on to you for what it may be worth. We have investigated the absorption type of refrigeration equipment for air conditioning and due to the sensitivity of this type of equipment to liquid levels and the excessive pressures prevailing, we have HEAT TRANSFER PRODUCTS AVIATION . AUTOMOTIVE . MARINE . INDUSTRIAL RADIATORS . SHUTTERS . OIL TEMPERATURE REGULATORS . CAR HEATERS . THERMOSTATS . HEAT EXCHANGERS | ||