To separate utilities, or not to separate utilities...

[Joey Nakayama]

My situation:

I own a triplex in Chicago, live on the first floor and rent out the upper two.

Cooking gas is separated for each unit, but a single hot water boiler heats the entire building. This last (brutal) winter, whenever the outside temp dipped below 10 degrees the boiler ran constantly and couldn't quite keep up. My gas bill was around $650 during the worst months.

Also, the radiators on the third floor don't work as well as those on the other floors. My third floor tenant is moving out at the end of the month, so now would be my opportunity to install a separate heating system for that unit.

My questions:

Are there simple ways to make my current system effective? (For instance, flush the current pipes to clear out any partial blockages)

What options are worth looking into for a separate system? (Electric baseboard heat, forced air system, hydroponic system?)

Can anyone recommend a great contractor in the Chicago area to speak with about this?

What would you do? Any thoughts from folks with experience in this area would be much appreciated.