Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
Crown Cayman CWI172 and Crown Cayman CWI207 are two non-condensing boilers from the Crown Boiler Co. Cayman (legacy) line. The Crown Cayman CWI172 is rated 172 MBH input, 144 MBH heating capacity and 83.2% AFUE, and the Crown Cayman CWI207 is rated 207 MBH input, 173 MBH heating capacity and 83.2% AFUE. Crown Cayman CWI207 lists 35 MBH more input than Crown Cayman CWI172 (207 MBH against 172 MBH). Both list the same published AFUE of 83.2%.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Crown Cayman CWI172 | Crown Cayman CWI207 |
|---|---|---|
| Input | 172 MBH | 207 MBH |
| Heating capacity | 144 MBH | 173 MBH |
| Efficiency (AFUE) | 83.2 % | 83.2 % |
| Domestic hot water | Integrated tankless coil in the boiler body (water boiler, not a combi burner) | Integrated tankless coil in the boiler body (water boiler, not a combi burner) |
| Water volume | 14.4 gal | 16.6 gal |
| Dimensions (A × B × C) | 22-1/2 × 28 × 40-7/16" | 25-3/4 × 30 × 40-7/16" |
| Venting | Category I natural draft into a lined masonry or listed metal chimney | Category I natural draft into a lined masonry or listed metal chimney |
| Fuel | Natural gas or propane | Natural gas or propane |
| AHRI net rating | 125 MBH | 150 MBH |
| Cast-iron sections | 6 | 7 |
| Tankless heater rating | 3.5 GPM GPM | 3.75 / 4.5 GPM |
Published ratings: the Crown Cayman CWI172 is rated 172 MBH input, 144 MBH heating capacity and 83.2% AFUE; the Crown Cayman CWI207 is rated 207 MBH input, 173 MBH heating capacity and 83.2% AFUE. Crown Cayman CWI207 lists 35 MBH more input than Crown Cayman CWI172 (207 MBH against 172 MBH). Both list the same published AFUE of 83.2%.
The boiler water content differs: the Crown Cayman CWI172 lists 14.4 gal, while the Crown Cayman CWI207 lists 16.6 gal. The dimensions differs: the Crown Cayman CWI172 lists 22-1/2 × 28 × 40-7/16", while the Crown Cayman CWI207 lists 25-3/4 × 30 × 40-7/16". The cast-iron sections differs: the Crown Cayman CWI172 lists 6, while the Crown Cayman CWI207 lists 7.
Both records print the same AFUE (83.2%), domestic-hot-water arrangement (Integrated tankless coil in the boiler body (water boiler, not a combi burner)), venting (Category I natural draft into a lined masonry or listed metal chimney) and fuel (Natural gas or propane), per the cited sources.
Crown Boiler Co.
The Crown Cayman CWI172 is a legacy cast-iron gas water boiler with an integrated tankless domestic coil: 172 MBH input over 6 sections with 144 MBH heating capacity and a 125 MBH AHRI net rating at 83.2% AFUE.
Crown Boiler Co.
The Crown Cayman CWI207 is a legacy cast-iron gas water boiler with an integrated tankless domestic coil: 207 MBH input over 7 sections with 173 MBH heating capacity and a 150 MBH AHRI net rating at 83.2% AFUE.
The Crown Cayman CWI207 lists 207 MBH, against 172 MBH on the Crown Cayman CWI172, per the cited documentation.
Both list the same AFUE of 83.2%.
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.