My air conditioning outside unit freezes up whenever we use it. We replaced our old unit with a larger one and ever since it has accumulated ice on the pipes whenever it runs for any amout of time? Is our new unit too big or could something have been installed wrong?

Did you match the out side unit with the indoor coil? If you went with a larger tonnage A/C system you may not be moving the amount of air and refrigerant you need to. Its OK to size the indoor coil a half ton bigger when the metering device fits the outside A/C. But the A/C tonnage should never be larger than the evaporator coil tonnage. Quick check is to check your return air filters and supply grills for air flow restrictions.