My air conditioner (Rudd compressor/heat pump) has started making a sporadic load buzzing noise. This noise often can be heard also coming from the air handler and ceiling areas (pipes?), what would cause this? Ive also noticed that the compressor coils no not get completely cold, is this normal?

If the noise it out side at the heatpump I would say it's the reversing valve coil your hearing.(not uncommon for it to get louder as your unit gets older). As far as the noise in the attic I don't know. Do you hear the noise after shut down of the equipment or when its running? Is the noise louder out side at the unit or inside?

My air conditioner (Rudd compressor/heat pump) has started making a sporadic load buzzing noise. This noise often can be heard also coming from the air handler and ceiling areas (pipes?), what would cause this? Ive also noticed that the compressor coils no not get completely cold, is this normal?
The noise happens when the unit is running, usually after it has run for a few minutes. The noise varies greatly, sometimes times its almost constant and loud other times its almost not there. It sounds just as loud inside as outside, I can hear it at both the heatpump and the air handler (and in-between, pipes run overhead in attic). Should the evaporator coils get completely cold in a heat-pump system (mine are just cold at the bottom)?