In Cave Creek, near East El Sendero Road and North 36th Place performing Fall preventative maintenance on an Amana and Carrier split systems. Upon arrival, removed and cleaned flame sensors and reinstalled. Checked ignitors and burners. Cycled systems on into heating mode. Checked volt and amp draws. Cleaned and tightened electrical connections. Checked back pressure safety switch and safety shut down. Both systems are new and running properly at this time. Recommended hard start kits for compressor start up.