Completed gas furnace replacement. Disconnected and removed old furnace. Set new furnace on blocks and reconnected the ductwork and gas piping. Installed new 2â€ pvc pipes for the intake and exhaust and ran to exterior of the home through the wall. Installed a new T4 thermostat and connected the wiring to the new furnace. Capped off the old furnace vent hole into the chimney. Thank you for choosing Black-Haak Heating. Please take a moment to fill out our online survey.