How much value would central heating and cooling add to an appraisal?

[Param Patel]

Hi everyone, 

I am a very new investor, and purchased my first multi-unit with the intention of updating the inside while I lived there... and later doing a cash out refinance. Forgive me if this is a novice question...

The home is approximately 100 years old, and had radiators throughout the entire property, as well as 2 boilers and a large oil tank in the basement. 

After purchasing, I removed all the radiators, boilers, and the large oil tank, then installed 2 central heating/cooling system's with air duct's throughout the entire home. I plan on doing more updates, such as finishing the basement into more livable square footage, but my question is just regarding the HVAC system's... 

Typically, how much value will the HVAC and ductwork improvement add to the appraisal amount later?