This article will target refrigeration systems that utilize air cooled condensers, but the efficiencies to be gained apply to the users of evaporative condensers as well.
First, let us remember a couple of important principles of refrigeration; 1) heat (energy) always flows from higher to lower temperatures, and 2) the function of the condenser is to remove the heat that was picked up by the refrigerant in the evaporator and condense the vapor back to a liquid.
So, if heat is to be removed from the refrigerant in the condenser, the temperature (and corresponding saturated pressure) of the refrigerant as it condenses from vapor to liquid must be greater than the temperature of the air flowing across the fins & tubes in the air cooled condenser. This temperature difference, generally referred to as the TD, is normally in the range of 10° to 20° above ambient. The TD is the driving factor that moves the energy from the refrigerant, through the tubes & fins of the condenser, back to Mother Nature’s air.
If the fins & tubes of the condenser are covered with dust, dirt, cottonwood fuzz, grass clippings, or worse, the air flow through the condenser will be reduced and the heat flow will be restricted. As a result, the TD between the condensing refrigerant and the ambient air will increase. The driving factor to move the energy has to become greater in order to make the exchange. In short, the condensing pressure rises, the compressor(s) work harder, the overall efficiency drops, and the electric meter spins faster. $$$
The spring of the year is an opportune time to clean your air cooled condensers, and it is a relatively simple procedure. Here’s how:
- Shut down the entire refrigeration system. (This is assuming that you don’t have a complex system with multiple compressors and coolers.)
- Disconnect the electrical power sources that supply the air cooled condenser – we don’t want folks getting a shock.
- Gain access to the condenser fins & tubes by removing any sheet metal covers, louvers and the like.
- On small air cooled condensers, use compressed air and / or a vacuum cleaner to remove the debris.
- On larger condensers wash out the coil section with a garden hose. Use care that you don’t flatten the fins with a high pressure nozzle.
- Once the coil section is clean you can re-assemble the unit and turn it back on.
It is a relatively simple process, but if you don’t want to tackle the project just give us a call; we’ll do it for you.