oliver

tell us about your furnace-age, brand, model. does it have a var speed blower? if not, you should just stick with a basic 13 SEER mdl like the XC13 with best matching Lennox evap coil.

I do recommend new refrigerant lineset.

you can check Lennox website as to db noise ratings.

IMO

Have you considered upgrading from an A/C to a heatpump? It shouldn't cost that much more. You gain the ability to inexpensively and comfortably heat your house during the milder cold weather. You would also protect yourself in the event natural gas gets expensive again.

The furnace is about 9 years old, and it is also a Lennox, but not sure which model. I'm guessing it is also a basic model since everyone who services them since we bought the house, tells us we have a builder's grade. I haven't done any research on the heatpump, but I am about to! Thank you tigerdunes and neohioheatpump for your replies!

I would go with the 14 SEER over the basic builder's grade 13 SEER, but I wouldn't go higher in SEER because you are limited by your furnace fan. Sometimes the 14 SEER has better btu outputs and EERs (Energy Efficiency Ratios) than the basic 13 SEERs. You should be able to get exact performance numbers for the condenser and indoor coil match from Lennox.

Make sure that the new indoor coil is a certified match with the condenser.

When you refer to noise, the condenser (outdoor unit)of the 14 SEER may be quieter than the 13 SEER. Higher SEER condensers usually use additional sound-deadening materials. The interior noise of the furnace fan, and the noise coming from the vents will not change because the furnace fan is the same.

Take care.