HVACopediaICP · Furnace
9 Medium/high pressure switch or PSR relay did not close or reopened
What the control is telling you
Medium or high pressure switch, or the PSR relay, did not close or reopened. Troubleshoot like code 3.
Applies to: ICP F9MAE / G9MAE modulating variable-speed condensing gas furnaces (060, 080, 100, 120 kBtu/h)
Likely causes
- Defective PSR relay
- Same causes as code 3 - vent, tubing, drain, wiring, wind
Test and repair steps
- Follow all code 3 checks (vent, pressure tubing, condensate drain, wiring).
- Check the PSR relay; replace if defective.
Save it for the next call
Star this code in the HVACopedia app and keep the whole library on your phone for jobs with no signal.
Source: ICP (F/G)9MAE Service and Technical Support Manual 440 04 4700 00, Figure 16 Troubleshooting Chart, p.35. Summarized in our own words; check the original manual for your model.
Homeowner looking at this code? See what it means for you and when to call a technician.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.