Mississauga, Ontario is a large city by Canadian standards, and it hosts a very grand commercial and industrial community. As such, it comes with its own housing issues, homeless populations, and when those combined, let to me being a witness to a suspected murder.
High rise buildings cannot operate without support, and a key member of ensuring comfort for everyone in the building’s superintendent. For a reduced living expense, and a pay check, they maintain the land, survey the parking, and deal with emergencies as they arise.
One autumn day, I, the controls contractor, was working in an apartment’s basement when the building’s new superintendent runs into the mechanical room. They’ve only just started two weeks prior, and it’s their first time working such a job.
When I first met him, he was happy, and excited to help, but when he found me he was panting, and his eyes are wild with panic and fright.
“You have to help me!” He begged, leaning on the wall for support. “Oh, God, you have to! I think I killed someone!”
Unwilling to abandon the clearly traumatized man in such a time of obvious need, I followed him to the elevator and we begin the ascent. When the elevator opened onto the top floor, I was greeted with crimson fluid dropping from the hallway ductwork.
“I didn’t look. I should have checked. Oh God, I’m going to get fired for this!” the superintendent moaned. Trying to be a voice of reason, I asked him to tell me what happened as we climb the stairs to the roof.
A paper had been circulated within the landholding company. It stated, “Please be advised that, due to the rapidly cooling temperatures, people without lodgings may seek warmth and shelter in all parts of the buildings. This includes HVAC equipment. Before starting up any air handling system, please ensure that all doors are sealed and that no one is in a position to endanger themselves or the occupants.”
I was beginning to understand.
A Makeup Air Unit (MAU or MUA) is a ventilation system that draws in outside air using a fan, treats it so it’s not too cold, and projects it into the structure so the occupants don’t spend all day breathing each other’s smells, farts, and exhalations.
I’d already seen the Makeup Air Unit in suspect. Most MAU’s have a bird screen, but this particular one had been without since it had been removed months ago. Most MAU’s had filters, but they had been sucked in and had ruined the fan, and they had not yet been replaced although the fan and belt had been. Most MAU’s had dampers that closed when not in operation, to prevent unwanted infiltration, but those had been locked open as the actuator had failed.
The unit had been offline all summer and the ductwork that traveled across the roof had been separated because they were installing a new electric heater downstream of the MAU. It had only been replaced earlier that week, and with the cold weather approaching, the new superintendent had been given the order to start the unit.
“I turned on the disconnect switch,” He gasped, “And there was this horrible grinding noise, and splattering over by the new coil, and then blood just started pouring from the unit.”
Dread and morbid curiosity led me to the service hatch just upstream of the heating coil. Twisting the catches, I pulled out the maintenance door and peered inside with my flashlight.
Blood and flesh and shattered bones were stuck to the coil, but they were not the only culprits; feathers were mixed into the nightmarish miasma.
Relief flooded my body, and I laughed as I walked back to the unit and opened the fan-chamber’s doors. There, ground into the scroll-cage, were twigs, eggs, and the broken bodies of dozens of pigeons.
It wasn’t hard to guess what he had killed.
Without a screen, filters, or dampers, and with no one inspecting the belt for months, a plague of pigeons had made the MAU their home, but they had done so in the worst possible spot, because the moment the superintendent had flipped on the power the MAU had started without warning, and had blended the birdies into the gory paste that now saturated the ductwork.
Apparently it took quite the cleanup effort to ensure no one got sick from the various bird bits that had infiltrated the ductwork, but, on the positive, no human was harmed, and the MAU got a full retrofit, so there were some good things to come out of that, including the lesson to always inspect the fan chamber before a startup.