Reasons Why I Cannot Get a Good Vacuum on My Condensing Unit

Vacuum Holding

• Vacuum holding refers to measurements you take from your condenser when checking it for proper pressure. Some vacuum pumps are designed to measure pressure in refrigerant lines while keeping the lines free of air and water vapor. For example, the manual for a condenser might say it needs to maintain a vacuum of 1,500 microns while equalizing pressure, then drop to 500 microns. Tests for problems are even simpler. If the vacuum cannot hold for a long period, such as 12 hours, you have a problem with the unit.

Quality Checks

• The lack of a proper or even vacuum force in the condenser could stem from the refrigerant in the system. A small amount of water can affect refrigerant efficiency. If dirt or air has entered the system, the vacuum might fail more easily or shift as a result of these new elements. If the vacuum is not constantly changing or slowly dropping but has simply changed, this could be a sign that particles have entered the system.

Leaks

• If vacuum force is consistently dropping, then the loss is often caused by leaks. Refrigerant leaks can be difficult to find because the refrigerant often escapes as a gas through small cracks or faulty connectors. You might want to call in a expert to fix the leak before trying to properly charge the system again. Restoring refrigerant pressure will not solve the problem if the leak persists.

Pumps

• A poor vacuum reading could also be the result of a failing pump. Old pumps or jammed pumping components might not be able to produce the proper amount of suction in the refrigerant lines to complete the cycle. The refrigerant levels and the pump force work together to create good flow, but if the vacuum is constantly failing, the pump itself might be at fault.