A complete York Affinity system, 2-Ton 2-Stage Heat Pump and matching air handler, were installed about a month ago. The air handler is very quiet so no complaints there, but when I go to bed there is a vibration noise from the heat pump that sometimes keeps me up. I read an excellent post by Kevin O'Neill under a related topic referring to his writing about quiet installations for a trade journal but I'm hoping to get more specific comments/suggestions this way.
The heat pump was installed outside the window of the bathroom that's off the side of my bedroom. It was installed in the same location as my 13 year old Trane 2-Ton Heat Pump, but a little further from the house (18" vs 12"). I never had this problem with the Trane and the headboard of my bed is along an opposing inside inside wall as it's always been.
I don't believe it's the fan, but a vibration from the compressor. If I stand in the bathroom I can hear the fan, but the sound I hear standing in a particular area of the bedroom, and while I'm in bed, is completely different... not a steady sound but a low pitch intermittent noise that speeds up and slows down along with the 2-Stage compressor. Per York's instructions the Heat Pump was replaced 2 weeks ago but the noise is still there. The installer is returning in 2 days.
Between the installation instructions Kevin O'Neill's post I at least understand this better but I'm open to any other comments or ideas. For example, an issue that concerns me involves the liquid and vapor lines... the vapor line is insulated but it's fastened up against the bottom of the basement joists with metal J-Clamps and the uninsulated liquid line is up against the outside of the J-Clamp... a source of the vibration? Kevin also mentioned installing a 360 degree loop in the liquid line outside to stop the sound from traveling to the house. And he also mentioned installing the outside unit on a concrete pad, whereas mine is on a cement coated plastic pad. I assume I could change this next summer by using 2x4's to support the bottom of the Heat Pump, raising the unit onto blocks, removing the existing pad and pouring a concrete slab.
Feel free to fire away.