Abstract: A portable unit indicates the precise time to close a fireplace damper door. The unit comprises a housing including a power source, and an electronic circuit, and an external heat sensor. The arrangement is such that the heat sensor is placed near the firebox and senses that a fire has been lit by the heat given off. The electronic circuit then stores this information and waits until the heat is no longer present. At this time, a fire extinguished indication is displayed, and a time delay circuit activated. If a fire is restarted before the delay circuit times out, the fire extinguished status is cleared and the process started over. If a fire is not restarted, and the delay circuit does time out, then a audible indication warns that the fireplace damper can now be manually closed to save energy.