Weil-McLain EG-35
The EG-35 steps the EG cast iron line to 100 MBH input with 85/82 MBH water/steam DOE heating capacity, 258 sq ft of steam coverage and the range's 84%/82% AFUE; discontinued in Canada, current in the US.
Key figures
- Max input
- 100 MBH
- Max CSA output
- —
- AFUE
- —
- Min input
- —
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Weil-McLain EG-35 in practice
At 100 MBH CSA input, the EG-35 delivers 85 MBH of DOE water heating capacity and 82 MBH in steam, with net AHRI ratings of 74 MBH water and 62 MBH steam covering 258 sq ft. Its AFUE is 84% in water and 82% in steam, and the boiler ships at approximately 430 lb — the same weight as the smaller EG-30.
The EG-35 shares the platform's Category I, B-vent design: vertical venting only, natural draft with a draft hood, an automatic vent damper and a 5" I.D. chimney collar. Manual data lists a 3" supply tapping, 2-1/2" return, 1/2" gas connection, 3/4" relief tapping and 12.3 gal of water content (8.4 gal to the steam waterline). Canada's EG / EG Steam page is discontinued; the US continues the model within EG Series 6 and Series 7.
Best suited to
- Small-to-mid water or steam loads near 100 MBH
- Chimney-vented replacements in older buildings
- Cross-referencing EG Series 6/7 ratings for a Canadian-discontinued unit
Applicability and support
- Model number
- EG-35
- 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 | 100 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 | 85 MBH | Water heating capacity per manual Table 20; matches the CA discontinued page's output figure. |
| DOE heating capacity, steam | 82 MBH | Steam heating capacity per manual Table 20. |
| Net AHRI rating, water | 74 MBH | Net AHRI water rating based on a 1.15 piping and pick-up allowance per the manual ratings notes. |
| Net AHRI rating, steam | 62 MBH | Net AHRI steam rating based on a 1.333 pick-up allowance per the manual ratings notes. |
| Net AHRI steam rating, area | 258 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; 5" 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 | 430 lb | Approximate shipping weight per the US spec tables and manual Table 20. |
| Operating limits and other | ||
| Boiler water content | 12.3 gal | Water content per manual Table 20. |
| Steam-to-waterline content | 8.4 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-35's ratings?
100 MBH CSA input, 85 MBH DOE water heating capacity, 82 MBH steam, 74 MBH net AHRI water, 62 MBH net AHRI steam (258 sq ft), and 84% water / 82% steam AFUE per the US spec tables and manual.
What size chimney does the EG-35 need?
A 5" I.D. chimney with a 20 ft maximum, used with Category I B-vent vertical venting only.
Does the EG-35 have a tankless coil option?
Yes. The CA discontinued page lists a tankless coil option for the EG / EG Steam line; the manual notes a tankless heater suffix in the model nomenclature.
Questions about the Weil-McLain EG-35?
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.
Compare and explore
- Weil-McLain EG-30 vs EG-35Comparison
- Weil-McLain EG-35 vs EG-40Comparison
- Weil-McLain EG-30Same series
- Weil-McLain EG-40Same series
- Weil-McLain EG-45Same series
- Weil-McLain EG-50Same series
- Weil-McLain EG-55Same series
- Weil-McLain EG-65Same series
- Weil-McLain EG-75Same series
- EG / EG Steam series hub
- Buying guide
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.