IBC Technologies · DC Series (discontinued)
IBC DC 20-125
The IBC DC 20-125 is a discontinued DC combi rated 20–125 MBH input and 18.6–110.8 MBH output at 95% AFUE, with a 4.0 USgpm maximum DHW flow, 105 lb weight and 120 ft of 3" venting per side.
Key figures
- Max input
- 125 MBH
- Max CSA output
- 110.8 MBH
- AFUE
- 95 %
- Min input
- 20 MBH
Input is gas energy consumed; output is heat delivered. Never size from input alone.
IBC DC 20-125 in practice
The DC 20-125 covers 20–125 MBH CSA input (5.6–36.6 kW) for 18.6–110.8 MBH output (5.4–32.5 kW) at 95% AFUE. Its low minimum input of 20 MBH made it the second-smallest low-fire point in the DC line, while its 110.8 MBH output lands within a fraction of the larger DC 33-124's 110.3 MBH.
It is a wall-hung combi with the standard DC coil ratings (43.5 psig space heating, 150 psig DHW) and a 4.0 USgpm maximum DHW flow, activating at 0.5 USgpm. The unit weighs 105 lb (48 kg), holds 0.5 USG (1.9 L) and draws 130 W at full fire with the internal pump; maximum boiler flow is 11 USgpm and the minimum is 3 USgpm.
The 20-125 appears in both DC I&O coverage lists (120-183-A-R11 and 120-183-A-R9). It vents 120 equivalent feet in 3" or 35 feet in 2" per side, and the DC Series is discontinued but still documented on IBC's Technical Information Portal.
Best suited to
- Owners documenting an existing DC 20-125 installation
- Homes wanting a low 20 MBH minimum fire with up to 110.8 MBH output
- Technicians comparing the 20-125 with the DC 33-124 and 33-160
Applicability and support
- Model number
- DC 20-125
- Canadian availability
- historical
- Production status
- discontinued
- ROMA supplies
- Confirmed at consultation
- ROMA services
- Confirmed at consultation
- Warranty
- Not verified
Where ROMA provides on-site service
On-site service is currently offered in Greater Vancouver, BC, including Vancouver, Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, West Vancouver, New Westminster, Port Coquitlam, Port Moody, Delta, Langley, Maple Ridge, Abbotsford, Chilliwack, White Rock, Pitt Meadows, Tsawwassen, Anmore, Lions Bay, Belcarra, Bowen Island, Mission. Everything else on this site is reference information you can use anywhere in Canada.
Specifications
Published specifications
Values as published by IBC Technologies. Units are shown with every value; notes flag conflicting sources or missing figures.
| Specification | Value | Note |
|---|---|---|
| Input | ||
| Input, minimum | 20 MBH | 5.6 kW |
| Input, maximum | 125 MBH | 36.6 kW |
| Output | ||
| CSA output, minimum | 18.6 MBH | 5.4 kW |
| CSA output, maximum | 110.8 MBH | 32.5 kW |
| Efficiency | ||
| Efficiency (AFUE) | 95 % | Per the DC specification table. |
| Domestic hot water | ||
| DHW input | 20 – 125 MBH | 5.6 – 36.6 kW |
| Max. DHW flow rate | 4 USgpm | |
| Flow to activate DHW | 0.5 USgpm | |
| Domestic hot water | Integrated DHW coil in a combination boiler | |
| Venting and air | ||
| Max. equivalent vent length, 3" | 120 ft | Each side. |
| Max. equivalent vent length, 2" | 35 ft | Each side. |
| Physical and connections | ||
| Weight (empty) | 105 lb | 48 kg |
| Pressure vessel water content | 0.5 USG / 1.9 L | |
| Electrical | ||
| Power use at full fire (internal pump) | 130 W | 120 V / 60 Hz. |
| Operating limits and other | ||
| Maximum boiler flow rate | 11 USgpm | |
| Minimum boiler flow rate | 3 USgpm | |
| Fuel | Natural gas or propane | The DC/HC specification table notes conversion kits must be ordered separately. |
| Gas supply pressure | 5 – 14 in. w.c. | |
| Ambient temperature | 32 – 122 °F | 0 – 50°C. |
| Space-heating water temperature | 50 – 194 °F | 10 – 90°C. |
| Domestic hot water temperature | 104 – 149 °F | 40 – 65°C. |
| Max. operating pressure, space-heating coil | 43.5 psig | DHW coil rated 150 psig; the unit ships with a 30 psig pressure relief valve. |
| Altitude rating | 12,000 ft | |
Manuals
- Installation & Operating Manual — DC 15-95 / 15-96 / 20-125 / 33-160, doc 120-183-A-R11120-183-A-R11 · 2020-04
Alerts documented for this model
Frequently asked questions
Why does the DC 20-125 weigh more than the 33-124?
IBC lists 105 lb (48 kg) for the 20-125 and 85 lb (39 kg) for the 33-124, even though their output ratings are close; the two models use different assemblies per the specification table.
Which manual covers the DC 20-125?
Both DC I&O manuals captured for this record cover it: 120-183-A-R11 and 120-183-A-R9.
What is the DC 20-125's minimum input?
20 MBH (5.6 kW) per the DC specification table.
Questions about the IBC DC 20-125?
Describe what the boiler is doing and get a straight answer about the next step.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.
Sources and verification
- IBC Technical Information Portal — DC series specification table · accessed September 9, 2026
- IBC Technical Information Portal — DC guides and manuals · accessed September 9, 2026
Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.