This is a virtual building tour of the Atwater. Actual tours are done every several months or so (more in good weather, less in inclement weather). However, some folks aren’t available when we do our tours, so I created this page.
Rooftop
Cooling Tower
The A/C in the Atwater works by taking the water line that goes into your unit’s HVAC, and uses a heat exchanger to cool that by the water loop that goes to the cooling tower. While water drips down from inside, air is sucked in through the grates and evaporation cools the water, which then cools your unit’s HVAC water via the heat exchanger.

This is how it looks now under Spectrum – the old media was so clogged it couldn’t be cleaned, it had to be replaced

From CMI’s time – A leak in the cooling tower allowed algae to grow into a river of slime. This also indicates the water wasn’t being treated properly
Equipment Room
The equipment room on the roof is where the boilers for your hot water and HVAC heating are kept, and where the heat exchanger for your HVAC cooling connects to the cooling tower. The water lines that go into your unit, and the cooling tower water loop both need to be treated with chemicals to prevent corrosion and growth of micro organisms.

Water treatment chemicals. Note there is no containment to prevent leaks, and there are stains on the floor which indicate leaks have happened.
We can see the water leaving the rooftop is at about 70F – coming back, after units have pulled heat from the water to heat their units, the temperature is now 67F or so.
When the cooling tower is used to cool the water during a hot day, it looks like this:
Water from the cooling tower exchanges heat with the water that goes into your unit via a heat exchanger – here’s a shot of it all assembled:
The old heat exchanger exceeded the normal resistance to pump water through, so it was rebuilt.
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Our building “talks” to itself via a control system (that’s outdated and is scheduled for replacement/upgrade)