Initial costs for the two systems are $350,000 and $500,000, respectively.
The presentation will address cost-effectiveness and maintenance costs.
According to Monica Sumner with the firm, the steering committee settled on the conventional system in June.
However, at Wednesday's steering committee meeting, Mayor Hugh Coomer made several inquires and elicited discussion on potentially making the building as green as it can be.
"We're a very environmentally-conscious community," said Coomer, also expressing his desire to explore full-on geothermal systems.
The mayor cited Centre College and its new buildings as being beacons and examples of being green-conscious.
Renovation more difficult
However, several concerns were raised about the possible change in HVAC.
City Engineer Earl Coffey pointed out it's easier to make brand-new buildings green, but harder to do so with renovated space. Because the project includes renovating the current city hall for use by the police department, Coffey said it would be substantially more difficult.
Though Sumner was hesitant to use the word "delay," changing plans now could delay the project by six weeks.
Several committee members voiced their hope of seeing substantial progress before the winter months come. Coomer, though, disagreed.
"I don't think we're under any deadline," he said.
The issue of being cost-effective also proved to be a contentious one.
"The government is promoting energy efficiency, and I think it behooves us to set an example," said Coomer.
"At any cost? We're using taxpayer dollars," responded Commissioner Janet Hamner.
Sumner said her firm was to send the design for the conventional system out for bids in three weeks, but the firm wants to do whatever the city deems necessary.
"We work for the city and will do anything the committee asks us to. But realize that if we switch systems now, at 80 percent (completion of the design), there will be additional time and money spent. But we will accommodate that," she said.
In the end, the committee did, however, vote to recommend the conventional water source heat pump system to the City Commission, which is expected to vote on which type of system to go forward with at Tuesday's meeting.