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
Both sizes sit on the same ClearFire-W platform. The CFW 400 and 500 both draw a 7 in w.c. minimum gas pressure, but water capacity more than doubles from 43 to 93 gal in the step.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Cleaver-Brooks ClearFire-W CFW 400 | Cleaver-Brooks ClearFire-W CFW 500 |
|---|---|---|
| Efficiency (manual) | 88 % | 88 % |
| Water content | 43 gal | 93 gal |
| Minimum gas pressure at gas train connection | 7 in w.c. | 7 in w.c. |
| MAWP | 125 psig | 125 psig |
The CFW 400 carries 88% efficiency and the CFW 500 88%. Both sizes sit on the same ClearFire-W platform. The CFW 400 and 500 both draw a 7 in w.c. minimum gas pressure, but water capacity more than doubles from 43 to 93 gal in the step.
Water content moves from 43 gal to 93 gal, which changes the system volume and buffer behaviour. Pressure rating: 125 on the smaller unit against 125 on the larger.
Both models are documented in the same official Cleaver-Brooks material, so the choice is a load and plant-layout decision: size to the calculated demand, then verify connections, venting and weight in the family document for the exact model.
Cleaver-Brooks
The Cleaver-Brooks ClearFire-W CFW 400 is a compact vertically fired firetube hydronic boiler documented by the official Model CFW O&M manual (750-296), with 43 gal water capacity and a 7 in w.c. minimum gas pressure.
Cleaver-Brooks
The Cleaver-Brooks ClearFire-W CFW 500 is a compact vertically fired firetube hydronic boiler documented by the official Model CFW O&M manual (750-296), with 93 gal water capacity and a 7 in w.c. minimum gas pressure.
The official Model CFW O&M manual prints water capacity (Table 4-1) and minimum/maximum gas pressures (Table 2-3); it does not print input/output ratings.
The manual states a nominal fuel-to-water efficiency of up to 88% depending on operating conditions.
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.