Since you don't have a var speed blower on your furnace, you are limited to a quality 13 SEER R-410a heat pump with best matching evap coil of same brand. You should want a condenser model that has electronic demand defrost.

A good DF thermostat plus outdoor sensor.

IMO

Based on my model number, on the furnace, I know I have a York Diamond 90 series furnace. Can you tell me if it is a single, 2 stage or a variable blower?

In the pic, the bottom is from the air handler, and has a model number. By chance, could you tell me what evap coil model might be in there and what a 410A coil might be a direct replacement?

Thanks

HE36348C210B2505AP - On Air Handler
P3URC14N09501 - On Furnace

Here is a link that might be useful:

Let Google be your friend.

See link below.

While you have a high eff condensing furnace, it does not have a var speed blower. This limits you to a 13 SEER heat pump. Still a worthwhile strategy.

You will need a matching indoor evap coil with the 13 SEER heat pump. Stay with model that has electronic demand defrost. R-410 a refrigerant.

IMO

Here is a link that might be useful: York Diamond Furnaces

Can anyone explain to my why I can't use a higher than 13 seer heat pump, if my furnace has a single stage blower?

Thanks!

Without going into technical details, your furnace has a conventional blower motor known as a PSC motor. It is not energy efficient when compared to a var speed blower motor or an ECM blower motor.

If you intend to purchase a 15+ SEER condenser, you would be simply wasting your money because you can not achieve the higher SEER condenser's capabilities with the conventional blower.

You should do your homework and at least be willing to accept correct advice when asking questions on this forum.

Go ahead and buy the higher SEER condenser. Doesn't mean a whit to me. It would be just be a bad mistake.

I am done here.

IMO