HVAC - Split Units

Usually there's a condensing unit outdoors and an air-handling unit indoors. Two pieces. Does your "also installed" mean there's a third unit?

Maybe if you tell us what the nameplates on the second or third units say, we can google it for you.

Slight correction - it is a condensate pump and not condensing unit next to the split unit.

Ah OK. There's no drain close enough for the condensate, so there's a pump to convey it there. Those are usually tin

y little motors, and only run when there's enough condensate to pump. I'd have the HVAC contractor start with that.

Agreed, the condensate pump can be replaced with a different (quieter) model. Might be helpful to get a larger pump/reservoir too; bigger motors are usually quieter and a larger reservoir would mean it runs less often.

There is also some possibility it could be relocated to an intermediate position between the indoor air handler and the final drain location -- the water would gravity-drain to a reservoir/pump at a more suitable intermediate location, and then be pumped to the final drain. So if there is a closet nearby it could be hidden there and muffled better. But it depends on your particular situation.

Most split systems use a gravity drain to get rid of the condensate, so a pump isn't necessary.

If pumps are installed improperly (not fastened securely), cheap, or dirty, they'll be loud.

http://www.hvacquick.com/products/residential/Condensate-Pumps/Condensate-Removal-Pumps/Aspen-Mini-Aqua-Condensate-Pump-Kits

I like uptown_joe's idea of moving the pump somewhere hidden. The pump will fail at some point and if you can move it somewhere out of the way (i.e. quiet) but still have it accessible for maintenance, that would be a good outcome.