14 DAY TRIAL // Regularly, when air conditioning (AC) machines run low on internal refrigerants, they need to work over-time in order to compensate for the loss. This translates into a greater strain the machines place on the electrical power grid, and also a significantly increased power bill for the average consumer. Now, experts from the Purdue University have devised a simple analysis technique, which warns when refrigerant levels are low, so that the AC owners can immediately refill them and avoid extra costs.
PU Professor of Mechanical Engineering James Braun, who has been in charge of the current research, said that the find was especially useful for air conditioning devices inside cars, which tended to leak more than any other type of AC, as well as households' central ventilation systems, which were subjected to the same flaw. According to the scientist, the “virtual refrigerant charge sensor” is able to make all that a thing of the past, and to save drivers and homeowners a lot of money.
When AC machines run low on refrigerants, they have to keep operating for longer, in order to achieve the predetermined temperature. With a properly filled unit, this is achieved in considerably less time than with one that is leaking, or that has low levels of refrigerant substances in it. And the thing is that owners rarely realize their machine is working for longer periods of time than it should, which leads to unpleasant surprises when the electricity bill comes in.
“Not only does the energy efficiency go down, but you also reduce the lifetime of the unit because it has to work harder, causing parts to wear out faster. It's also very time consuming and costly to have a technician check the refrigerant and charge it up to specification. To accurately learn how much charge is in the system, you have to remove all of the refrigerant and weigh it, a procedure that requires a vacuum pump and is quite time consuming,” Braun said.
The sensors are fairly simply to attach to the device. Braun explained that they simply had to be placed outside the cooling tubing in the machine, at various established points. A blinking light is then used to indicate if refrigerant levels are low, and a technician could easily connect a PDA to the system, and view the levels without having to take it all out. The finds were presented in Louisville, Kentucky, at the June 22nd meeting of the American Society of Heating, Refrigerating and Air Conditioning Engineers. A paper also appears in a recent issue of the journal HVAC&R Research.