Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
Boilers.ca is a brand of ROMA Heating & Cooling · Licensed gas contractor LGA0202903
Comparison
Verdict in brief
The Royal CH-180 is the largest residential Royal CH boiler and the top of the 80,000-180,000 BTU/hr residential range: 18-180 MBH input with 165 MBH heating capacity and a 143 MBH net AHRI water rating, against the CH-150's 139 MBH and 121 MBH — still 95.2% AFUE in the same shared cabinet.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Dunkirk Royal CH-150 | Dunkirk Royal CH-180 |
|---|---|---|
| Central-heating input, minimum | 15 MBH | 18 MBH |
| Central-heating input, maximum | 150 MBH | 180 MBH |
| AFUE | 95.2 % | 95.2 % |
| Heating capacity | 139 MBH | 165 MBH |
| Net AHRI water rating | 121 MBH | 143 MBH |
| Turndown | Up to 10:1 | Up to 10:1 |
| Dimensions (H x W x D) | 28.23" x 17.4" x 16.93" | 28.23" x 17.4" x 16.93" |
Both models cap the residential Royal CH line — the five sizes from 80,000 to 180,000 BTU/hr that the official CH page describes — at 95.2% AFUE with up to 10:1 turndown in the shared 28.23 x 17.4 x 16.93 in wall cabinet with 3/4" NPT CH connections.
The CH-150 fires 15-150 MBH to 139 MBH of heating capacity and a 121 MBH net AHRI water rating. The CH-180 fires 18-180 MBH to 165 MBH of heating capacity and a 143 MBH net AHRI rating, per the official brochure table.
The CH-180's 18 MBH minimum fire against the CH-150's 15 MBH is the only behaviour difference below the 150's ceiling. Above the residential ladder, Dunkirk documents the commercial CH models on a separate commercial page with their own ratings and connections.
Dunkirk Boilers
The Royal CH-150 is Dunkirk's 150 MBH-class wall-hung residential heating-only boiler: 15 to 150 MBH central-heating input at 95.2% AFUE with 139 MBH heating capacity, a 121 MBH net AHRI water rating and up to 10:1 turndown.
Dunkirk Boilers
The Royal CH-180 is Dunkirk's 180 MBH-class wall-hung residential heating-only boiler: 18 to 180 MBH central-heating input at 95.2% AFUE with 165 MBH heating capacity, a 143 MBH net AHRI water rating and up to 10:1 turndown.
The brochure table prints 165 MBH of heating capacity and a 143 MBH net AHRI water rating against 139 MBH and 121 MBH — 26 MBH of heating capacity.
No — the CH-180 is the top residential size (the range runs CH-80 through CH-180). Dunkirk's commercial Royal CH models are documented separately.
The one the heat-loss calculation picks: if the design-day load approaches 139 MBH of capacity, the CH-180 buys headroom; below that the CH-150 condenses the same at a lower minimum fire.
A consultation includes a heat-loss review so the size is right the first time.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.
Sources and verification
Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.