Dad has run that dryer for years and does not need a lecture about lint. What he probably does not have is a system that catches the part he cannot see. The lint trap is the part he sees. The duct behind the machine and the flap on the outside wall fill up with no warning, and a dryer that cannot move air runs hot, takes longer on every load, and is the machine that causes trouble in the middle of the night.
Local option: New Plan Care gives families in the St. Louis area in-home help so a parent can stay home: companionship, help with bathing and dressing, meals, and overnight care. Call (314) 405-0887.
Name one owner for each part of the run
The vent has three stretches, and each one needs a name beside it. The trap at the door of the machine is Dad's job on every load. It takes a few seconds, and it holds best when it is tied to the same moment each time, such as pulling the trap before the first load of the day. The duct from the back of the dryer to the wall, and the cap or flap on the outside of the house, are not Dad's job. Put a family member or a hired service on them and write the name down. If nobody is written down, the duct will not get cleaned, because each person will assume someone else has it.
Check the run on the first visit
Pull the dryer out from the wall far enough to see the connector. If the machine runs on gas, shut the gas valve off first and reconnect the line before you leave. Then look at what connects the machine to the wall. Is the hose metal, or is it a thin foil or plastic flex hose? Foil and plastic flex hoses sag, trap lint, and collapse, and they are the first thing to replace. Is the hose kinked, crushed, or pushed against the wall with the machine sitting on it? Measure the run if you can, because a long path with bends moves less air than a short straight one. Check the manual for the maximum duct length the maker allows.
Go outside and see whether the exterior flap opens freely when the dryer runs. A flap that stays shut, sticks, or is packed with lint or nesting material is restricting the whole system. Then check the symptoms Dad can report without climbing behind anything. A load that takes noticeably longer than it used to, a laundry room that feels warm after a run, a hot smell, or a dryer that shuts off mid-cycle all point to restricted airflow. Keep a short note of each change so you can see the trend rather than guessing at it.
What to ask the duct service before you book
When you compare services, ask the questions that show what they will actually do. Ask whether the cleaning covers the whole run from the back of the dryer to the outside cap, or only the part they can reach easily. Ask whether they will check the hose material and length and tell you in writing if it should be replaced. Ask whether they will open, test, and clear the exterior flap. Ask what the written record will contain: the condition of the hose, what was cleared, and what they recommend next. A service that will not put that in writing has not told you what you bought.
Keep the schedule on paper
Write the interval on the calendar or the fridge with the owner's name beside it. Set the interval by how much the machine runs. A dryer used every day needs a shorter gap than one used once a week, and any change in drying time moves the next check up. Keep the trap reminder in the same visible spot every time. If a hired non-medical caregiver is in the house on laundry days, emptying the trap can be part of the list they already work through, but the duct and the flap stay with the family or the service.
If the machine smells of burning, feels hot on the outside, or stops with a load still wet, switch it off and leave the door shut. Do not run it again until someone has looked at the whole run.
Next move tonight
Tonight, pull the dryer out, look at the hose, and write down its material and whether it kinks. Clear the trap, and check the outside flap if you can reach it safely. Then write two names on the fridge: the trap owner and the duct owner. If the hose is foil or flexible plastic, or the drum is taking longer than it used to, book the duct service this week. For a starting point on local options in the St. Louis metro, go to Local Help in St. Louis.