UniMac QN Washer Error Code E Hd: Too Hot to Drain
On UniMac QN washer-extractors, E Hd is the too hot to drain message, shown when that option is enabled: the water in the drum is hotter than the control allows it to drain. Press any key to clear the display and wait for the water to cool. If E Hd shows often, call us.
Low: an operator message; the cycle waits and the load stays safe.
What does UniMac error code E Hd mean?
Some laundries protect their drain lines from very hot water, and the QN control can be set to hold off draining until the water has cooled below a limit. When that option is on and the drum water is hotter than the limit, the control waits and shows E Hd. Pressing any key clears the display. The cycle waits for the water to cool, and the load stays safe. It is not a breakdown. If it appears often, the water in the drum may simply be hotter than the limit allows, a temperature sensor may be reading the water as hotter than it is, or the hot water supply setting may fill the drum too hot to start with. The message is a reminder of a limit that someone chose, so check whether the limit still suits your plumbing before assuming the machine is to blame.
Affected models and control systems
This applies to UniMac QN washer-extractors of 20 to 100 lb, such as the UCA020QN, in the CHM1792C family, only when the too-hot-to-drain option is enabled.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- E Hd on the display
- Cycle pausing before the drain step
- Water in the drum that is too hot to touch
Possible causes
Listed in UniMac's documentation
- Water in the drum still hotter than the drain limit allows
- A temperature sensor reading the water as hotter than it is
- A hot water supply setting that fills the drum too hot
Other likely causes — what usually sits behind error code E Hd on this control. A technician confirms which one it is before any part is replaced.
- A building water heater turned up high so wash water arrives very hot
- A cool-down step in the program that is too short for the limit
- A limit set lower than the program's wash temperature
Safe checks before calling for service
- Press any key to clear the display.
- Wait for the water to cool before the machine drains.
- Keep the door closed while the water is hot.
- Try again.
- If E Hd shows often, note which program and call us.
How a technician diagnoses error code E Hd
- Ask which program was running and what the wash temperature is set to.
- Compare the drum water temperature with a thermometer reading.
- Check the limit setting against the program wash temperature.
- Test the temperature sensor circuit against the actual temperature.
- Check the hot water supply temperature at the machine.
- Adjust the setting or replace the sensor that fails.
- Measuring hot water inside a washer carries a scald risk.
- Changing the temperature limit is a service-menu setting for this machine.
- Telling a bad sensor from hot supply water needs a thermometer and a meter.
Technical reference
- Document
- Washer-Extractor Programming CHM1792C_SVG, Part No. F8641001ENR4, Error Codes Table 29 (pp. 100-107)
- Maker documentation
- UniMac owner support
- Edition
- Part No. F8641001ENR4, January 2020
- Models / control
- CHM1792C family washer-extractor (QN models, 20-100 lb) front-end control
- Section
- Error Codes, Table 29, pp. 100-108 (PDF pages equal printed pages)
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related UniMac washer error codes
Is E Hd an error?
It is a message. The control holds off draining because the water is hotter than the limit.
Does my load stay safe?
Yes. The cycle simply waits for the water to cool.
Can I turn it off?
It only appears when the option is enabled. We can look at the setting during a visit.
Need help with UniMac error code E Hd?
A technician confirms the cause on site and gives you the price in writing before any work starts.