Weil-McLain CGa-7
The CGa-7 is the second-largest CGa Series 4 size of the cast iron line discontinued in Canada in 2023: 200 MBH CSA input, 170 MBH DOE heating capacity and a 147 MBH net AHRI rating at 84% AFUE.
Key figures
- Max input
- 200 MBH
- Max CSA output
- 170 MBH
- AFUE
- 84 %
- Min input
- —
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Weil-McLain CGa-7 in practice
The CGa-7 reaches 200 MBH CSA input for 170 MBH of DOE heating capacity and a 147 MBH net AHRI rating at 84% AFUE, stepping its vent size to 7" per the US Series 4 page. It is one of the two largest sizes of Weil-McLain's cast iron natural-draft Series 4 boiler, carrying the generation's stainless steel burners, built-in low water cut-off and easy top-access flueway cleaning.
In Canada the CGa disappeared from new sales after Weil-McLain Canada's June 30, 2023 production cut-off, announced April 27, 2023, under the federal efficiency standard for non-condensing residential boilers under 300,000 BTUH. The discontinued CA page describes the Series-3-era Canadian generation at 52-245 MBH inputs with vertical B-vent venting only; the Series 4 CGa-7 here is part of the 38-233 MBH US model set documented by manual 550-100-223/0425.
Best suited to
- Large homes and light-commercial chimney-vented plants near 200 MBH
- Contractors mapping the CGa generations between the Canadian and US markets
- Replacement documentation for larger cast iron natural-draft boilers
Applicability and support
- Model number
- CGa-7
- 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 | 200 MBH | CSA input per the US Series 4 product page. |
| Output | ||
| DOE heating capacity | 170 MBH | DOE heating capacity per the US Series 4 product page. |
| Net AHRI water rating | 147 MBH | Net AHRI water rating per the US Series 4 product page. |
| Efficiency | ||
| Efficiency (AFUE) | 84 % | 84% AFUE per the US Series 4 page; the CA discontinued page lists up to 84% for the Series-3-era Canadian units. |
| Venting and air | ||
| Venting | Category I, B-vent — vertical chimney venting only, natural draft | Per the CA discontinued page (Cat. 1 venting, B-Vent; vertical vent only, 50 psi relief option); the US Series 4 page lists a 7" vent size for the CGa-7. |
| Operating limits and other | ||
| Fuel | Natural gas or propane | Propane requires a conversion kit per the CA product page. |
Manuals
- CGa Series 4 Boiler Manual, 550-100-223/0425550-100-223/0425 · 2025-04
Alerts documented for this model
- CONFIRM CONFIGURATION
- CONFIG MISMATCH
- AUTO LIMIT OPEN
- MANUAL LIMIT OPEN
- FALSE FLAME
- IGNITION FAULT
- FLAME LOST
- BOILER OUT OPEN
- BOILER OUT SHORT
- HARDWARE FAULT 1
- HARDWARE FAULT 2
- HARDWARE FAULT 3
- HARDWARE FAULT 4
- HARDWARE FAULT 5
- HARDWARE FAULT 6
- HARDWARE FAULT 7
- HARDWARE FAULT 8
- CH VOLTAGE HIGH
- DHW VOLTAGE HIGH
- SPILL SWITCH
Frequently asked questions
What are the CGa-7's ratings?
200 MBH CSA input, 170 MBH DOE heating capacity, a 147 MBH net AHRI rating and 84% AFUE, with a 7" vent size per the US Series 4 product page.
When did Weil-McLain stop selling the CGa in Canada?
The April 27, 2023 news release set a production cut-off of June 30, 2023 for the CGa and CGi; Weil-McLain Canada sold remaining inventory only while supplies lasted.
Does the CGa Series 4 have a low water cut-off?
Yes — the US Series 4 page lists a built-in low water cut-off as a feature of the current generation.
Questions about the Weil-McLain CGa-7?
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 — CGa (discontinued) · accessed September 8, 2026
- Weil-McLain Canada — Residential boiler efficiency changes (Apr 27, 2023) · accessed September 8, 2026
- CGa Series 4 Boiler Manual 550-100-223/0425 · 550-100-223/0425 · accessed September 8, 2026
Facts checked September 8, 2026. Last updated September 8, 2026. Technical reviewer: not yet assigned.