Technical troubleshooting guides, fault code explanations, and diagnostic help for Trane HVAC systems — from Thomas Hoffmann Air Conditioning & Heating in St. Louis.
Trane heat pumps provide both heating and cooling from a single outdoor unit, making them an efficient choice for St. Louis homeowners. But when a heat pump stops working properly — especially in heating mode — diagnosing the problem requires understanding how heat pumps work differently from conventional furnaces and air conditioners. This guide covers …
Short cycling — when your Trane furnace turns on, runs for a few minutes, shuts off, and then starts the cycle again — is one of the most common and damaging furnace problems. The furnace never completes a full heating cycle, your home stays cold, and the repeated starts put excessive wear on the heat …
When you call for heat and nothing happens — the furnace starts but never lights, or the burners ignite briefly and then shut off — you have an ignition failure. On Trane furnaces, this typically triggers a 2-flash fault code after the control board has attempted and failed ignition three times. This guide walks through …
A 3-flash fault code on a Trane furnace indicates a pressure switch fault — specifically, the pressure switch failed to close (or opened unexpectedly) during a heating cycle. This is one of the most common Trane furnace fault codes, and it has several possible causes ranging from a blocked vent (a 5-minute fix) to a …
When your Trane air conditioner is running but your home isn't cooling down, it is one of the most frustrating situations a St. Louis homeowner can face — especially in the middle of a July heat wave. The system is on, the outdoor unit is running, but the house stays warm. This guide covers every …
A 4-flash fault code on a Trane furnace means the high limit switch has opened — the furnace detected that the heat exchanger was getting too hot and shut down the burners to prevent damage. This is one of the most important safety features on your furnace, and it is also one of the most …