Weil-McLain EG-55
The EG-55 is the 200 MBH EG size with 169/166 MBH water/steam DOE heating capacity, 521 sq ft of steam coverage and 84%/82% AFUE, sharing the 7" I.D. chimney and 585 lb cabinet with the EG-50; discontinued in Canada.
Key figures
- Max input
- 200 MBH
- Max CSA output
- —
- AFUE
- —
- Min input
- —
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Weil-McLain EG-55 in practice
At 200 MBH CSA input the EG-55 produces 169 MBH of DOE water heating capacity and 166 MBH in steam, with net AHRI ratings of 147 MBH water and 125 MBH steam covering 521 sq ft. Its AFUE is 84% in water and 82% in steam, and it ships at approximately 585 lb.
The EG-55 uses the same atmospheric cast iron, Category I B-vent design with vertical venting only — draft hood, automatic vent damper and 7" I.D. chimney collar — and the manual lists 3" supply, 2-1/2" return, 1/2" gas and 3/4" relief connections, 17.3 gal of water content and 11.2 gal to the steam waterline. The EG is discontinued in Canada; the US continues it as Series 6 and Series 7.
Best suited to
- Larger steam or water loads near 200 MBH
- Buildings replacing an atmospheric cast iron boiler with a 7" chimney
- Comparing the top of the small-pair EG sizes
Applicability and support
- Model number
- EG-55
- Canadian availability
- historical
- Production status
- discontinued
- ROMA supplies
- Confirmed at consultation
- ROMA services
- Confirmed at consultation
- Warranty
- Series terms
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 EG Series 6/7 spec tables and the EG Series 7 manual ratings table (Table 20). |
| Output | ||
| DOE heating capacity, water | 169 MBH | Water heating capacity per manual Table 20; matches the CA discontinued page's output figure. |
| DOE heating capacity, steam | 166 MBH | Steam heating capacity per manual Table 20. |
| Net AHRI rating, water | 147 MBH | Net AHRI water rating based on a 1.15 piping and pick-up allowance per the manual ratings notes. |
| Net AHRI rating, steam | 125 MBH | Net AHRI steam rating based on a 1.333 pick-up allowance per the manual ratings notes. |
| Net AHRI steam rating, area | 521 sq ft | Steam square-foot rating per manual Table 20; the CA discontinued page's published range ends at 750 sq ft, which does not match the EG-75's 733 sq ft. |
| Efficiency | ||
| AFUE, water | 84 % | 84.0% AFUE in water per manual Table 21 and the US spec tables. |
| AFUE, steam | 82 % | 82.0% AFUE in steam per manual Table 21 and the US spec tables. |
| Venting and air | ||
| Venting | Category I, B-vent — vertical vent only, natural draft with draft hood and automatic vent damper; 7" I.D. chimney x 20 ft | Per the US spec tables (chimney size) and the CA discontinued page (Cat. 1, B-vent, vertical vent only). |
| Physical and connections | ||
| Supply connection | 3" | Supply tapping O is 1 x 3" on every EG/PEG size per the Series 7 manual connections section. |
| Return connection | 2-1/2" | Return tapping P is 1 x 2-1/2" on every EG/PEG size per the Series 7 manual connections section. |
| Gas connection | 1/2" | Gas connection F is 1/2" on EG/PEG-30 through -55 per the Series 7 manual. |
| Relief valve | 3/4" tapping | Water boilers use a 3/4" tapping on the side with a 30 psi relief valve; steam boilers use a 15 psi relief valve on a top tapping per the Series 7 manual. |
| Weight | 585 lb | Approximate shipping weight per the US spec tables and manual Table 20. |
| Operating limits and other | ||
| Boiler water content | 17.3 gal | Water content per manual Table 20. |
| Steam-to-waterline content | 11.2 gal | Steam-to-waterline water content per manual Table 20. |
Manuals
- EG Series 7 Boiler Manual, 550-100-225/0425550-100-225/0425 · 2025-04
Alerts documented for this model
- CONFIRM CONFIGURATION
- CONFIG MISMATCH
- AUTO LIMIT
- MANUAL LIMIT
- 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
- POWER (flashes once per second)
- Flash code 2
- Flash code 5
- Flash code 6
- ALL LED'S FLASHING
- Solid LWCO LED
- POWER + TSTAT/CIRC
- POWER + DAMPER
- POWER + FLAME
- DAMPER
- LIMIT
- FLAME
- LWCO
Frequently asked questions
What are the EG-55's ratings?
200 MBH CSA input, 169 MBH DOE water heating capacity, 166 MBH steam, 147 MBH net AHRI water, 125 MBH net AHRI steam (521 sq ft), and 84% water / 82% steam AFUE per the US spec tables and manual.
What is the EG-55's shipping weight?
Approximately 585 lb, the same as the EG-50, per the US spec tables and manual.
Which generations replaced the EG-55 in the US?
The same model continues in EG Series 6 (manual 550-142-303/1120) and EG Series 7 (manual 550-100-225/0425); "EG-6" and "EG-7" are series shorthand, not model numbers.
Questions about the Weil-McLain EG-55?
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 — EG / EG Steam (discontinued) · accessed September 9, 2026
- Weil-McLain — EG Series 7 Gas Boiler · accessed September 9, 2026
- EG Series 7 Boiler Manual 550-100-225/0425 · 550-100-225/0425 · accessed September 9, 2026
Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.