IPSO Washer-Extractor Error Code E Pr: Pressure Switch Check
E Pr on an IPSO CHM495R washer-extractor is a low level pressure switch error that belongs to the production test cycle. The switch was in the wrong position after the first fill step. Power down to clear it, and confirm a normal formula is selected.
Low: tied to a test cycle and rarely seen in daily production.
- Code
- E Pr
- Maker
- IPSO
- Equipment
- Industrial laundry
- Applies to
- CHM495R family washer-extractor front-end control (20-100 lb)
What does IPSO error code E Pr mean?
E Pr is mostly a factory-style check rather than a daily alarm. During the production test cycle, the control fills the drum a little, then asks the low-level pressure switch what position it is in. If the switch is not where it should be after that first fill step, the control posts E Pr. Plant staff rarely see it in daily use. The manual says to power down to clear it. If it does appear on a normal formula, the pressure switch, its air tube or its wiring may not be behaving as the control expects. The simplest explanation is that a test cycle was selected by mistake, so the formula selected is the first thing to confirm. After that, a pinched tube or a sticking switch is a reasonable suspect. The control itself rarely causes it.
Affected models and control systems
CHM495R washer-extractors, 20 to 100 lb, with the front-end control. Other controller generations use different codes.
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 Pr shown early in a cycle
- Cycle stops after the first fill
- Test cycle accidentally started
- Code returns on a normal formula
Possible causes
Listed in IPSO's documentation
- Low-level pressure switch in the wrong position after the first fill step
Other likely causes — what usually sits behind error code E Pr on this control. A technician confirms which one it is before any part is replaced.
- A low-level pressure switch stuck in the wrong position
- A pinched or disconnected air tube to the pressure switch
- A production test cycle selected by mistake
- A switch input on the control that reads the wrong state
Safe checks before calling for service
- Remove power to clear the message, as the manual directs.
- Check that a normal formula is selected and not a test cycle.
- Do not open the control to inspect the switch.
- Tell us if the code shows up in regular production.
How a technician diagnoses error code E Pr
- Read the code history and verify which cycle was running.
- Check the air tube to the pressure switch for pinches and leaks.
- Test the switch contacts with the drum empty and at the first fill level.
- Check the wiring and connectors to the switch with power locked out.
- Replace the switch or tube only if it fails the test.
- The pressure switch and its wiring sit inside the control area with live circuits. Judging switch position at a set water level requires a meter and a controlled fill. Opening the cabinet to look at it is not an operator job.
Technical reference
- Document
- Washer-Extractor Programming CHM495R_SVG, Part No. F8208501ENR10, March 2017, Error Codes (pp. 36-37)
- Edition
- Part No. F8208501ENR10, March 2017
- Models / control
- CHM495R family washer-extractor front-end control (20-100 lb)
- Section
- Error Codes table, pp. 36-37 (E Pr only on Design 1 models; Ed01-Ed11 on Design 2 and 3 models)
- 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 IPSO industrial laundry error codes
Is E Pr a serious problem?
Usually not. It is tied to the production test cycle.
Why did I see it on a normal wash?
Check that the right formula was selected. If so, the switch or tube may be the cause.
Will E Pr clear itself?
Power-down clears the message. It will return if the switch is still wrong.
Need help with IPSO error code E Pr?
A technician confirms the cause on site and gives you the price in writing before any work starts.