Weil-McLain CGi-5
The CGi-5 is the first of the larger CGi Series 5 sizes, from the cast iron line Canada discontinued in 2023: 119 MBH CSA input, 102 MBH DOE heating capacity and an 89 MBH net AHRI rating at 84% AFUE.
Key figures
- Max input
- 119 MBH
- Max CSA output
- 102 MBH
- AFUE
- 84 %
- Min input
- —
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Weil-McLain CGi-5 in practice
The CGi-5 raises the Series 5 line to 119 MBH CSA input with 102 MBH of DOE heating capacity and an 89 MBH net AHRI rating at 84% AFUE, holding the 3" vent connection with 5" natural-draft venting on the US Series 5 page. The generation pairs cast iron sections with an insulated steel jacket, natural draft and direct exhaust capability, no vertical draft hood or mechanical vent damper, a built-in low water cut-off and intermittent electronic ignition.
The CGi is discontinued in Canada: Weil-McLain Canada announced on April 27, 2023 that production of the mid-efficiency CGi and CGa hot water boilers would end with a June 30, 2023 cut-off under federal efficiency standards, followed by 20+ years of promised parts support. weil-mclain.ca's discontinued page data (50-233 MBH inputs, up to 85.1% AFUE) covers the Series-3-era Canadian units, while this Series 5 CGi-5 belongs to the generation Weil-McLain now sells in the US.
Best suited to
- Homes with chimney or sidewall venting and loads near 100-120 MBH
- Contractors comparing the Canadian CGi generation with the US Series 5 set
- Cast iron boiler documentation for post-2023 replacement research
Applicability and support
- Model number
- CGi-5
- 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 Weil-McLain. Units are shown with every value; notes flag conflicting sources or missing figures.
| Specification | Value | Note |
|---|---|---|
| Input | ||
| Input, maximum | 119 MBH | CSA input per the US Series 5 product page. |
| Output | ||
| DOE heating capacity | 102 MBH | DOE heating capacity per the US Series 5 product page. |
| Net AHRI water rating | 89 MBH | Net AHRI water rating per the US Series 5 product page. |
| Efficiency | ||
| Efficiency (AFUE) | 84 % | 84% AFUE per the US Series 5 page; the CA discontinued page lists up to 85.1% for the Series-3-era Canadian units. |
| Venting and air | ||
| Venting | Category I B-vent (chimney) or Category III AL29-4C stainless steel (sidewall) | Per the CA discontinued page, which notes Category I vent sizes increase from 3" to 4" up to the CGi-3 size and 3" to 5" on larger sizes; the US Series 5 page lists a 3" vent connection with 5" natural-draft venting for the CGi-5. |
| Operating limits and other | ||
| Fuel | Natural gas or propane | Propane requires a conversion kit per the CA product page. |
Manuals
- CGi Series 5 Boiler Manual, 550-100-629/0126550-100-629/0126 · 2026-01
Alerts documented for this model
Frequently asked questions
What are the CGi-5's ratings?
119 MBH CSA input, 102 MBH DOE heating capacity, an 89 MBH net AHRI rating and 84% AFUE per the US Series 5 product page.
What happened to the CGi in Canada?
Weil-McLain Canada phased out the CGi with a June 30, 2023 production cut-off under federal efficiency standards, per its April 27, 2023 news release; remaining stock sold only while supplies lasted.
Is the CGi a combi boiler?
No. Neither the discontinued CA page nor the US Series 5 page lists a combi or tankless-coil variant for the CGi, and Boilers.ca records every CGi model with combi: false.
Questions about the Weil-McLain CGi-5?
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
- Weil-McLain Canada — CGi (discontinued) · accessed September 8, 2026
- Weil-McLain Canada — Residential boiler efficiency changes (Apr 27, 2023) · accessed September 8, 2026
- CGi Series 5 Boiler Manual 550-100-629/0126 · 550-100-629/0126 · accessed September 8, 2026
Facts checked September 8, 2026. Last updated September 8, 2026. Technical reviewer: not yet assigned.