If your heat pump system is rated to operate at temperatures as low as -25°C, it means the system is designed to maintain efficient heating performance down to that temperature. However, it does not necessarily stop working when the temperature drops below -25°C. Here’s what happens:
1. Performance Decline:
• Below the rated temperature, the heat pump’s ability to extract heat from the outdoor air diminishes, so its heating capacity decreases significantly.
2. Backup Heating:
• Many heat pumps include an auxiliary or backup heating system, such as electric resistance heaters or a gas furnace, to provide additional heat if the outdoor temperature drops too low for the heat pump to meet demand.
3. Shutdown Possibility:
• If the temperature falls far below the system’s design limit and no backup system is available, the heat pump may shut down to protect its components from damage.
4. Cold-Climate Heat Pumps:
• Some modern cold-climate heat pumps are capable of continuing to operate even below their rated temperatures, though with reduced efficiency.
Key Takeaway
A heat pump rated to -25°C is optimized to deliver reliable heating at that temperature, but extreme conditions below that may require supplemental heat. If you’re in a region with temperatures regularly dropping below this limit, ensure your system includes an adequate backup heat source.