MEMPHIS, Tenn. --  As Memphians celebrate Independence Day with barbecues, fireworks, and a day off from work for some employees, severe heat and broken air conditioners mean another day on the job for service technicians at HVAC companies. "Basically what I'm doing is cleaning this thing with chemicals here. We don't want any build-up because the condenser coil is the lungs of the system. If it's clogged up with dirt and debris, it can't cool as it should," said Biafra Warren, Choates Air Conditioning, Heating and Plumbing Service Technician. Central Gardens hosts annual patriotic parade Almost all week long, temperatures in the 90s have almost suffocated the Mid-South making much-needed relief for customers during the sweltering heat. "Yes, a lot of calls like this. In the Mid-South we have high humidity levels and that's very normal. It may be 90 degrees, but it feels like 130 degrees, which is not good for the homeowner," Warren said. WREG Weather Expert Jake Daltons says, "The heat index will feel like upwards of 110 at times. We saw yesterday [Wednesday] it felt as hot as 115. So, another hot day and it's going to be humid as well." Excessive Heat Warning issued across Memphis, Mid-South Service technicians say their best advice to customers is regular maintenance on their A-C units. "It's simple just to have maintenance on it," Warren said. "It's almost like a car, if you don't get the oil changed this thing will crash on you." Warren says he is standing by on call, even on a holiday, to get the AC running again at Memphis area homes during the dog days of summer. "I love what I do. I love meeting customers and it's nothing like bringing the holidays in with cold air," Warren said. The U.S. Department of Energy says using a combination of proper insulation, energy-efficient windows, and doors, day lighting, shading, and ventilation will usually keep homes cool with less air conditioning.