Dunkirk Boilers · DMG (DMG-240 / DMG-380)
Dunkirk DMG-240
The Dunkirk DMG-240 is the wall-hung condensing boiler of the DMG pair — positioned 'Residential/Light Commercial' on the official page: 36 to 241 MBH input, 216 MBH heating capacity, 95% AFUE (ENERGY STAR), 6.7:1 turndown and a 50 psi ASME rating, with an optional floor base kit.
Key figures
- Max input
- 241 MBH
- Max CSA output
- —
- AFUE
- 95 %
- Min input
- 36 MBH
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Dunkirk DMG-240 in practice
The DMG-240 is the wall-hung member of Dunkirk's DMG condensing pair, which the official page positions for 'Residential/Light Commercial' use and which can also sit on the optional floor base kit. The brochure table prints 241 MBH maximum input (36 minimum) with 216 MBH heating capacity, a 188 MBH net water rating and 95% AFUE (ENERGY STAR), with a 6.7:1 modulation turndown ratio per the product page.
It is built around a 316L stainless steel heat exchanger and burner with direct spark ignition and a combination flame sensor and igniter, a built-in boiler loop pump, a digital temperature display with diagnostics, optional plug-and-play CSD-1 kit (manual-reset low water cut-off and high limit), and the included LABOR SAVER manifold. Dimensions are 17-3/4" (W) x 31-1/16" (H) x 23" (D) with a 145 lb ship weight, 0.8 gallons water content, 50 psi ASME rating, boiler supply/return at 1" and gas at 3/4" NPT.
The DMG-240 page carries current documents (Rev. A manual MGC-22-240-REV-A, spec sheets and submittals), so this model is recorded as current. The ratings are the US-market figures Dunkirk prints; no Canadian listing was verified on the pages checked on September 9, 2026, so canadianStatus stays 'unknown'. Gas work belongs with a licensed contractor against the DMG-240 IOM.
Best suited to
- Light-commercial and larger residential hydronic loads around 216 MBH of heating capacity
- Wall-hung installations with an optional floor base when wall mounting is not preferred
Applicability and support
- Model number
- DMG-240
- Canadian availability
- unknown
- Production status
- current
- 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 Dunkirk Boilers. Units are shown with every value; notes flag conflicting sources or missing figures.
| Specification | Value | Note |
|---|---|---|
| Input | ||
| Input, maximum | 241 MBH | Input maximum in MBH as printed in the official DMG 240/380 brochure table. |
| Input, minimum | 36 MBH | Input minimum in MBH as printed in the official DMG 240/380 brochure table. |
| Output | ||
| Heating capacity | 216 MBH | Heating capacity in MBH as printed in the official DMG 240/380 brochure table. |
| Net water rating | 188 MBH | Net water rating in MBH (piping and pickup allowance of 1.15) as printed in the official DMG 240/380 brochure table. |
| Efficiency | ||
| AFUE | 95 % | 95% AFUE (ENERGY STAR) as printed in the official DMG brochure table and on the product page. |
| Venting and air | ||
| Venting | Coaxial polypropylene 3"/5" or 2-pipe polypropylene 3" | Coaxial and 2-pipe diameters as printed in the official DMG 240/380 brochure table. |
| Physical and connections | ||
| Dimensions (W x H x D) | 17-3/4" (W) x 31-1/16" (H) x 23" (D) | Per the official DMG 240/380 brochure table. |
| Ship weight | 145 lb | Per the official DMG 240/380 brochure table. |
| Boiler water content | 0.8 gal | Per the official DMG 240/380 brochure table. |
| ASME rating | 50 psi | Tested for 50 psi (DMG-240) or 80 psi (DMG-380) ASME, maximum allowable working pressure, per the brochure; the product page lists a 50 psi relief valve. |
| Heat exchanger | 316L stainless steel | As printed on the official pages and brochure. |
| Electrical | ||
| Power supply | 120 V ac, 60 Hz, 1 phase, less than 12 A | Per the official DMG 240/380 brochure (15 A circuit recommended). |
| Operating limits and other | ||
| Turndown | 6.7:1 | Modulation turndown ratio as printed on the product page. |
| Connections | Boiler supply/return 1"; system supply/return with LABOR SAVER manifold 1-1/2" copper; condensate 3/4" NPT; gas 3/4" NPT | Per the connection/tappings table in the official DMG 240/380 brochure; LABOR SAVER primary/secondary manifold included. |
| Control | Digital temperature display with diagnostics and programmable settings | High limit/electronic ignition control module with a built-in boiler loop pump, direct spark ignition and combination flame sensor/ignitor, per the brochure. |
Manuals
- DMG 240 Condensing Boiler Manuals Rev. A (MGC-22-240-REV-A)MGC-22-240-REV-A (Rev. A) · 2022-09
- DMG 240/380 Brochure (240011835 Rev. 09/02/21)240011835 Rev. 09/02/21
Alerts documented for this model
Frequently asked questions
Is the DMG-240 a condensing boiler?
Yes — it is condensing on a 316L stainless steel heat exchanger, rated 95% AFUE (ENERGY STAR) with a 6.7:1 turndown ratio.
Is the DMG-240 wall-mounted?
Yes — it is wall-hung by design, with an optional floor base kit; the DMG-380 is the floor-standing model of the pair.
Is the DMG-240 a combi boiler?
No — it is a heating-only boiler; the optional indirect tank sensor supports domestic hot water through an indirect tank rather than an internal DHW plate.
Questions about the Dunkirk DMG-240?
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
- Dunkirk — DMG 240 product page · accessed September 9, 2026
- DMG 240/380 Brochure (240011835 Rev. 09/02/21) · accessed September 9, 2026
- DMG 240 Condensing Boiler Manuals Rev. A (MGC-22-240-REV-A) · accessed September 9, 2026
Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.