Arkansas HVACR NewsMagazine November 2020

S tate, National, Chapter News Tech News

system overcharged, particularly during heating season with a heat pump.

ACCA Standard for Charging

Outdoor Temperature Indoor Temperature

Local Data 75-degree 63-degree

Indoor Wet Bulb Temperature

Solutions for past problems- Unfortunately, with incorrect duct configuration and insufficient air flow, equipment will not last and economy and comfort are not obtainable. The customer expected an expert to have installed the previous system correctly and you must convince the customer that the expert is now sitting across the table. When we formulate solutions for homeowners, we must take the time to educate our customers with understandable facts using everyday terms. It is the contractor ’s responsibility to explain that an air conditioning system with poorly designed duct costs them in comfort and economy. If the system is over 10 years old, technology sometimes outstrips its useful life. Just as cell phones are updated several times a year, the HVAC industry takes substantial steps about every two years that make an investment in updated equipment attractive every 12 to 15 years. A responsible contractor makes sure the entire package delivers comfort, economy and reliability.

Photo 4: Duct Sizing

Finally, the fourth question is “Did I charge the system properly?” Charging the system at completion of installation or a service call is a complicated process. ACCA standards for charging the system stand at an indoor temperature of 75 degrees with a wet bulb of 63 degrees. Your technicians or start up crews will most likely never see these conditions, so it remains imperative that the air flow is correct, so the charge is as close as possible. We should have a basic understanding when we charge the system and ambient and or indoor temperatures are higher than ACCA standards, we are leaving the system slightly undercharged. When we charge the system and ambient and or indoor temperatures are cool, we leave the