Run the heat and the cooling before showings
Turn each system on, listen for a short cycle, and change a dirty filter.
Turn the heat on and wait. Stand at a supply vent until the air is actually warm, not merely until the thermostat clicks. Write the time it took and whether every vent you can reach did the same. A system that blows cold at one room and warm at another is a line on the repair list, not a story you tell at the showing.
If the house has cooling, switch to it after the heat test and wait again until a vent is cool. Do not run both claims on the same minute. Listen for a short cycle: the blower starts, stops, and starts again before the room has changed. A short cycle can be a clogged filter. Slide the old filter out, read the size printed on the frame, and write that size down. A common one-inch filter is often about $10 to $30 depending on the size. Write the size on the new frame or on a card in the closing folder so the next change is not a guess.
Replace the filter before photo day if it is grey and packed. A clean filter does not fix a system that will not start. If the heat or the cooling refuses to run, stop and put that on the repair list before you schedule photos. A quiet system is easier to explain than a dead one, and a technician's written note is what you want in the folder. Ask what they found and what it will cost before you approve the work.
On showing day, set the temperature to something ordinary and leave it. Do not shut the system off to hide a noise. If a bedroom vent is closed, open it so the room is not stale. Check the condensate line or the pan if you know where it is and you have seen a drip there before. A small drip goes on the function list. Do not wipe it and hope. The test you already wrote down is the one you repeat the morning of the first visit.
What to do
- Run the heat until a vent is warm, and note any room that stays cold.
- Run the cooling until a vent is cool, if the house has it.
- Replace a dirty filter and write the size down.
- Put any system that will not start on the repair list before photo day.