Bosch Error Code b8: Refrigerant sensor past service life (Heat Pump)
Bosch error code b8 on a heat pump means: Refrigerant sensor past service life. It is also called Bosch diagnostic code b8.
Homeowner? What Bosch code b8 means for you
Usually minor Your heat pump is reporting: Refrigerant sensor past service life. This code is usually informational or minor. The safe checks below often clear it; call us if it keeps showing up.
Safe things you can check yourself
- Check the thermostat: right mode (Heat or Cool), set a few degrees past room temperature, and fresh batteries if it uses them.
- Check both breakers and the outdoor disconnect box beside the outdoor unit; all should be ON.
- Look at the air filter. If it is grey and clogged, replace it; a blocked filter causes many shutdowns.
- In winter, keep snow and ice off and away from the outdoor unit. A short defrost cycle with steam is normal.
- Try one reset: turn the power off for 30 seconds, then back on. If the code comes back, stop resetting and call a technician.
Call (647) 657-2977Book a service call
Licensed technicians serving Vaughan, Toronto and the GTA.
What does Bosch error code b8 mean?
The indoor A2L sensor has reached the end of its rated life.
Applies to: Bosch IDS Light BOVA15-24/36/60 and IDS Premium Connected BOVA36-20/60-20 R-454B heat pump outdoor units
Common causes of Bosch code b8
- Sensor end of life
Bosch models that use code b8
BOVA15-24BOVA15-36BOVA15-60BOVA36-20BOVA60-20
Other Bosch Heat Pump codes
All Bosch Heat Pump error codes →
Bosch code b8: homeowner questions
What does Bosch code b8 mean?
Refrigerant sensor past service life. The indoor A2L sensor has reached the end of its rated life.
Is it safe to keep using my heat pump with code b8?
Usually yes. Code b8 is normally minor, but if it keeps coming back have it checked.
Can I reset Bosch code b8 myself?
You can try one reset (power off for 30 seconds, then on). If Bosch code b8 comes back, the cause is still there and a licensed technician should check it.
Who can fix Bosch code b8 near me?
Aurora Star Tech Inc. repairs Bosch heat pumps in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.
Homeowner help: AC Running But Not Cooling: What to Check · Heat Pump Not Heating or Blowing Cold Air
Source: Bosch IDS Light installation BTC 762003308 D (02.2025), Fault Code Table 23 and 17.12 Error Code Troubleshooting, p.42-59; Bosch IDS Premium Connected installation BTC 762003301 D (02.2025), Fault Code Table 22 and 18.12 Error Code Troubleshooting. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.