Which heat pump for a sunroom?
Updated October 24, 2026
A sunroom is mostly windows: it loses a lot of heat in winter and gains a great deal in summer sun. Cooling often sets the size.
Heating at -23 °C4,400BTU/h
Cooling at 30 °C4,400BTU/h
Recommended system
ZERO 9,000 wall unitfrom $2,199 · DIY
Covers 100% of the heating load at -23 °C
The 9,000 BTU wall unit is not eligible for any rebate.
See on kanartic.caLoad by floor area and city
| Area | Toronto (-18 °C) | Montreal (-23 °C) | Edmonton (-32 °C) | Cooling Montreal | System (Montreal) | DIY price |
|---|---|---|---|---|---|---|
| 120 sq ft | 2,500 | 2,900 | 3,400 | 3,000 | ZERO 9,000 wall unit | $2,199 |
| 160 sq ft | 3,100 | 3,500 | 4,200 | 3,500 | ZERO 9,000 wall unit | $2,199 |
| 200 sq ft | 3,900 | 4,400 | 5,200 | 4,400 | ZERO 9,000 wall unit | $2,199 |
| 250 sq ft | 4,500 | 5,000 | 6,000 | 4,800 | ZERO 9,000 wall unit | $2,199 |
| 300 sq ft | 4,800 | 5,400 | 6,400 | 4,900 | ZERO 9,000 wall unit | $2,199 |
| 400 sq ft | 6,000 | 6,000 | 7,300 | 5,000 | ZERO 9,000 wall unit | $2,199 |
Good to know
- Compare both columns: in summer the load often exceeds the winter load.
- Blinds or low-e glazing cut the solar gain sharply.
- The smallest wall unit (9,000 BTU) is enough for most sunrooms, but it is not eligible for rebates.
- An uninsulated three-season room cannot be heated efficiently in mid-winter.