Miele T1 heat-pump dryer (24-inch, ventless): field service manual

Covers: Miele T1 compact heat-pump dryers sold in the US (TWI180WP and related T1 WP models). Series names only.

Single sourceBrands: Miele6 components

A 24-inch ventless heat-pump dryer that runs on 120 V. Air passes through two door fluff filters, then a plinth (foam) filter in front of the heat exchanger behind a lower access panel. Condensate goes to a container in the control area or out a drain hose. Almost every drying complaint traces back to lint in one of these filter stages.

Safety first

Unplug before opening panels.
Heat exchanger fins are sharp: avoid bare hands.
Sealed system: refer to an EPA 608-certified technician.

How it works

Air loop: the drum fan pushes warm, moist air through the door fluff filters, then the plinth filter and the heat exchanger. The cold side of the heat pump condenses moisture; the warm side reheats the air before it returns to the drum.

Water: condensed water is pumped to the condensate container (shown as Empty container when full) or, if fitted, to a drain hose. Some steam features use collected condensate water.

Monitoring: when airflow drops, the control shows a Clean out airways message at the end of the program. The dryer will only run with the plinth filter fitted correctly and the heat-exchanger access panel closed.

Electrical: listed as a 120 V / 60 Hz appliance, about 15 A on retailer spec data, so it plugs into a standard outlet.

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work. © 2026 OnCall Tech. Original content; not a reproduction of any manufacturer document.Generic part photos (not of this brand): Clothes dryer with its vent duct in a small laundry closet by Introspectivedsgn, Pexels License

Diagnostic guides for this appliance

Guide · Dryer

Ventless dryer not drying: cleaning the filters, condenser and heat exchanger

Ventless dryers depend on clean air passages. Lint that gets past the door filter settles on the condenser or heat exchanger and drying time climbs. Clean every filter stage first, then the condenser or exchanger, then check the water path.

8 steps ~40 mineasy

Guide · Dryer

Dryer squeaks, squeals or thumps: drum rollers, idler pulley, glides and rear bearing

Drum noise usually comes from four wear parts: the drum support rollers (thump, squeak), the idler pulley (squeal or whine), the front glides or bearing slides (scraping) and, on some designs, a rear drum bearing (squeal, drum moves front to back). Take the belt off and turn the drum by hand to find which one it is. Replace rollers as a set.

9 steps ~75 minmoderate

Guide · Dryer

Replacing a broken or slipping dryer drum belt

A broken belt leaves the motor spinning with no drum movement. Open the cabinet, put the new belt around the drum with the ribbed side against the drum, then route it through the idler and onto the motor pulley. Inspect the idler and rollers while you are in there.

7 steps ~50 minmoderate

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Whirlpool HybridCare heat-pump dryer (27-inch, ventless): field service manual

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