Comprehensive side-by-side analysis of efficiency ratings, specifications, and performance metrics
GEM
Head to Head
Keston C 36P Combi
Keston • 90.8%
Both Boilers
Available FREE through ECO4 scheme
Keston C 36P Combi leads with 90.8% efficiency, providing better performance and energy savings.
Both GEM CC1 15/20 and Keston C 36P Combi are available at no cost through the government ECO4 scheme. Take the next step today.
✓ Government Approved Scheme ✓ No Hidden Costs ✓ Professional Installation ✓ Energy Efficient
