Speed Queen Dryer tH Error Code: Causes & Fix

What is the Speed Queen Dryer tH error?#

tH on a Speed Queen dryer means the exhaust thermistor is reading open or shorted — the sensor that monitors exhaust-air temperature has failed or lost its connection. An open sensor throws tH the instant you start the dryer. It is a moderate sensor repair; the machine is not dangerous to be near, but it will not regulate drying until the thermistor is restored.

tH on a Speed Queen Dryer: likely causes and repair cost#

On a Speed Queen Dryer, the tH code signals: thermistor open or shorted — exhaust temperature sensor fault.

Typical professional repair: $75–$175 · Difficulty: moderate · usually a technician job

Technician diagnostic sequence for tH:

1. Locate the exhaust thermistor on the blower housing or exhaust duct
2. Measure resistance — should read approximately 10K ohms at room temperature
3. Inspect the two-wire connector for green oxidation or moisture intrusion
4. Check wiring harness routing to ensure it is not near the heating element

Parts a technician may check or replace: Exhaust thermistor

Field note: Speed Queen dryer thermistors monitor exhaust air temperature to regulate the drying cycle. An open thermistor (infinite resistance) causes tH immediately on startup. A shorted sensor (near zero ohms) may cause the dryer to overheat before displaying tH.

How to troubleshoot the tH error yourself#

tH is an exhaust-sensor fault. Owner steps are inspection; the measurement and replacement are for a technician. With the dryer unplugged:

1. If you can reach the blower housing or exhaust duct, locate the exhaust thermistor.
2. Check its two-wire connector for green oxidation or moisture intrusion — as the table above notes, corrosion there is a common cause.
3. Confirm the wiring harness is routed away from the heating element so heat has not damaged it, and that the sensor has not dislodged from its housing.

Stop and hand it to a technician to measure the sensor and replace it. As the table above shows, a healthy exhaust thermistor reads about 10K ohms at room temperature; an open sensor reads infinite and a shorted one near zero, and confirming that needs a meter. A shorted sensor is worth prompt attention because, as the table above warns, it can let the dryer overheat before tH appears — so do not keep running it while you wait for service.

Is the Speed Queen Dryer tH error worth fixing?#

tH is the least expensive Speed Queen dryer repair in this group. The table above lists $75 to $175 for a professional fix, essentially the exhaust thermistor plus modest labor. That is a small sum next to a new dryer, and Speed Queen machines are built for long service, so restoring a working exhaust sensor is clearly worth it on a sound unit. This code almost never justifies replacing the dryer — the part is cheap and central to safe, well-regulated drying. Only consider a new machine if this one is already old and failing in several places.

Speed Queen Dryer tH: frequently asked questions#

What does the tH error mean on a Speed Queen Dryer?#

It means the exhaust thermistor is reading open or shorted, so the control has lost its exhaust-temperature signal. An open sensor triggers tH right at startup. The thermistor needs replacing.

Is it safe to keep using a Speed Queen Dryer that shows the tH error?#

An open sensor just stops the dryer regulating properly, but a shorted one can let it overheat before flagging tH, so do not keep running it. Have the sensor checked before relying on the machine.

Can I clear the tH error myself, or do I need a technician?#

You can inspect the connector for corrosion and the harness routing, but measuring and replacing the thermistor needs a meter and disassembly — a technician job.

How much does it cost to repair the tH error on a Speed Queen Dryer?#

The table above shows $75 to $175 for a professional repair, covering the exhaust thermistor and the labor to reach it.

Which parts usually fail when a dryer throws the tH code?#

The exhaust thermistor itself is the most common failure. Damaged wiring, a corroded connector, or a sensor dislodged from its housing cause the same reading.

Is a Speed Queen Dryer with the tH error worth repairing?#

Yes. At $75 to $175 for a cheap, essential sensor, it is well worth fixing on a long-lived Speed Queen dryer.

Why does an exhaust thermistor failure trigger the tH error?#

The control depends on the exhaust thermistor to regulate the drying cycle. When the sensor reads open or shorted instead of its normal value near 10K ohms, the board cannot trust the temperature and posts tH.