There was a dark, oily puddle on the concrete floor beneath the main valve.

“The main line has been tampered with,” Carl said.

He knelt down, careful not to touch the wet floor.

“The emergency release valve is gone,” he said.

“Gone?” I asked.

“Someone removed the safety cap,” Carl said. “And the pressure regulator is cracked.”

“Was it Jake?” I asked.

“It had to be,” Carl said. “This isn’t wear and tear. This was done with a wrench.”

He stood up, his face dark in the shadow of the flashlight.

“If the system starts up without that regulator, the pressure will build until the tank ruptures,” he said.

“That would ruin the whole heating system,” I said.

“It would do more than that,” Carl said. “It could crack the building’s foundation.”

“The city would condemn the building,” I realized.

“Exactly,” Carl said. “A condemnation order would force everyone out, and the repairs would cost more than the building is worth.”

“She wants to destroy it so you can’t have it,” I said.

Carl didn’t answer.

He shone the light back on the copper pipes, his hand steady but his jaw clenched.