Appraisal value for HVAC vs window unit

[Jeff Williams]

Any one have input one experience with the appraisal value of residence with window units vs. HVAC? My wife and I are in process of purchasing a Quadplex built in 1940s and currently has baseboard electric heat, and window a/c units. When it gets appraised, will it be much lower because of this? Will in benefit to change everything over to central HVAC? I am pretty sure I have heard on a podcast that as long as it is renting out, don't worry about changing. This might be true, but just wondering how the appraisal might look?