Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
The HC 15-95 edges out the HC 23-84 with 85.5 MBH output against 74.8, a lower 15 MBH minimum fire, 95% AFUE against 94%, and a 10 USgpm maximum flow against 9. It weighs 91 lb versus 85 lb and uses a different manual.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | IBC HC 23-84 | IBC HC 15-95 |
|---|---|---|
| Input, minimum | 23 MBH | 15 MBH |
| Input, maximum | 84 MBH | 95 MBH |
| CSA output, minimum | 21.2 MBH | 14.4 MBH |
| CSA output, maximum | 74.8 MBH | 85.5 MBH |
| Efficiency (AFUE) | 94 % | 95 % |
| Power use at full fire (internal pump) | 126 W | 128 W |
| Weight (empty) | 85 lb | 91 lb |
| Pressure vessel water content | 0.37 USG / 1.4 L | 0.37 USG / 1.4 L |
| Maximum boiler flow rate | 9 USgpm | 10 USgpm |
| Minimum boiler flow rate | 2 USgpm | 2 USgpm |
| Max. operating pressure, space-heating coil | 43.5 psig | 43.5 psig |
| Max. equivalent vent length, 3" | 120 ft | 120 ft |
| Max. equivalent vent length, 2" | 35 ft | 35 ft |
The HC 23-84 covers 23–84 MBH input and 21.2–74.8 MBH output; the HC 15-95 covers 15–95 MBH input and 14.4–85.5 MBH output. The 15-95's lower minimum fire and higher maximum output make it the more flexible of the two across a range of loads.
Efficiency also favours the 15-95 at 95% AFUE versus 94%, and its maximum boiler flow is 10 USgpm against 9, though both keep a 2 USgpm minimum and the same 0.37 USG (1.4 L) vessel. Weight rises modestly to 91 lb (41 kg) from 85 lb (39 kg), and full-fire power draw is 128 W versus 126 W.
Everything else matches: 43.5 psig space-heating coil, supplied 30 psig relief valve, 5–14" w.c. gas, 50–194°F water, 12,000 ft altitude and 120 ft of 3" / 35 ft of 2" venting per side. The 23-84 uses manual 120-185-A-R9 and the 15-95 uses 120-185-A-R10.
IBC Technologies
The IBC HC 23-84 is a discontinued heating-only boiler rated 23–84 MBH input and 21.2–74.8 MBH output at 94% AFUE, sharing the DC 23-84's ratings on the heating side without the DHW coil.
IBC Technologies
The IBC HC 15-95 is a discontinued heating-only boiler rated 15–95 MBH input and 14.4–85.5 MBH output at 95% AFUE, weighing 91 lb with 120 ft of 3" venting per side.
The HC 15-95 at 95%, against 94% on the HC 23-84.
About 10.7 MBH at the top end: 85.5 MBH versus 74.8 MBH.
HC 23-84: 120-185-A-R9; HC 15-95: 120-185-A-R10.
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.