Douglas Machines Pot and Pan Washer Error Code Er05: Low Water
Er05 means an operation was attempted without adequate water in the wash tank, so the machine will not start the heat or the wash. Check that the tank holds water and the drain valve is closed, then run a fill and start the cycle. Do not bypass the probe.
Medium: the machine will not heat or wash until the water level is right, which is often an easy fix.
- Code
- Er05
- Maker
- Douglas Machines
- Equipment
- Pot & pan washers
- Applies to
- Digital touch pad 3125/5072 with PC board 3126/5071
What does Douglas Machines error code Er05 mean?
Before it heats or washes, a Douglas pot and pan washer checks that its wash tank holds enough water. The low-water probe and float switch report the level to the board. If a cycle is started and the board does not see enough water, it refuses to switch on the heater or the wash pump and shows Er05. The reason is simple: the heater would burn out in a dry tank and the pump would run dry. The usual cause is also simple, because the tank was never filled or the drain valve was left open. The maker adds a warning that is easy to forget on a slow afternoon: do not leave the machine idle for more than four hours with water in the tank. Water evaporates from a hot tank, and the next person to start a cycle finds Er05 because the level has dropped below the probe, not because anything has failed. A level probe that reads dry because of grease or food film gives the same message with a full tank, and the maker's daily cleaning of the low-water probe and float switch is the answer to that. A fill valve or drain problem is the remaining case.
Affected models and control systems
Douglas Machines door-type pot, pan and utensil washers with the digital touch pad 3125 or 5072 and PC board 3126 or 5071.
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
- Er05 appears when a cycle is started
- The tank looks low or empty
- The heater and pump stay off
- Er05 appears with a full tank
Possible causes
Listed in Douglas Machines's documentation
- Tank never filled
- Water lost by evaporation while the machine sat idle
- Level probe reading dry
- Fill valve not passing water or drain valve leaking
Other likely causes — what usually sits behind error code Er05 on this control. A technician confirms which one it is before any part is replaced.
- A probe coated with baked-on grease that insulates it from the water
- A float switch that sticks in its guide because of dried detergent
Safe checks before calling for service
- Check that the tank holds water and the drain valve is closed.
- Run a fill, then start the cycle.
- Clean the low-water probe and float switch, as the maker's daily cleaning says.
- If the tank is full and Er05 stays, call us. Do not bypass the probe.
- Tell us how long the machine had sat idle before the code appeared.
How a technician diagnoses error code Er05
- Confirm Er05 and check the actual water level in the tank.
- Check the drain valve seal and the fill valve for proper operation.
- Clean the low-water probe and test that the board sees it as wet in a full tank.
- Free the float switch and check its travel and signal.
- Check the wiring from the probe to the board.
- Replace the probe, switch or board input only after the test names it.
- Probe and float switch wiring is behind panels on a machine with a hot tank.
- A probe that reads dry in a full tank needs a meter test at the board.
- Running the heater with no water can burn out the elements, so bypassing the probe is never acceptable.
Technical reference
- Document
- Douglas Machines Troubleshooting Guide (2024 edition), Touch Pad Error Code Value Table p.25
- Edition
- 2024 edition
- Models / control
- Digital touch pad 3125/5072 with PC board 3126/5071
- Section
- Troubleshooting - Error Code Value Table (PGM LED) printed pp. 14-15; Touch Pad Error Code Value Table printed p. 26
- 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 Douglas Machines pot & pan washer error codes
Why does Er05 appear after a quiet afternoon?
The maker warns against leaving water in the tank for more than four hours, because evaporation lowers the level.
Er05 shows but the tank is full. Why?
The probe or float switch may read dry because of grease, so it needs cleaning and testing.
Can I jump the probe to run it?
No. The heater could burn out without water covering it.
Need help with Douglas Machines error code Er05?
A technician confirms the cause on site and gives you the price in writing before any work starts.