Too-low-flow-temperature on a Worcester Bosch Greensource Split HP Hydrolight / Hydrocomfort: Info: Too low flow temperature
Short answer
On a Worcester Bosch heat pump, Too-low-flow-temperature means: Info: Too low flow temperature. The heat pump keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Info: Too low flow temperature.
Part involved: flow temperature.
When it shows: Flow below set point for more than 15 minutes; heat pump shuts down.
Likely causes:
- Flow below set point for more than 15 minutes; heat pump shuts down.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Information only |
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
Resetting itself: yes.
Manual reset: Info symbol clears once read.
What you can check
- Read and note the full alarm text shown on the controller and pass it to your installer.
What the engineer will check
- Investigate heat output and flow.
Who to ask for: heat pump installer / heating engineer.
Certification: None specific for hydraulic checks; MCS-certified installer recommended for system changes.
What you might notice
Sources
- Installation, Commissioning and Servicing Instructions Greensource Hydrolight and Hydrocomfort (ODU 7.5-12) ↗ · 6 720 806 629 (2013/02) · page 67 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026