Are there shorter communication cables? I purchased a 3 zone, 30,000 BTU perfect air system.

There are 25' communication cables included with each indoor air handler. This 70' option is for when you have lineset runs from the air handler to condenser that are longer than the included 25'. If you have any more questions regarding your specific order please call us at 888-377-2850 and we will be glad to assist you.