The answer is no , If you have to add refrigerant you have a leak some where and need to have a professional technician find and repair it. Why you ask? Because an a/c unit or heat pump is a sealed system and letting refrigerant leak out and constant recharging is bad for the environment and your system. If a system is getting recharged all the time it is probably getting contaminants in it which can cause your system to fail prematurely. Nobody wants to replace their system unless they have to. Also refrigerant is being restricted and some phased out which is causing the prices to skyrocket, its much cheaper and alot less headache to have it repaired properly. So stop recharging your system and save money in the long run by having the leak repaired, save the environment and save money and headaches.