Weil-McLain ECO Tec 150-C
The ECO Tec 150-C is the mid-size ECO Tec combi: 150 MBH of heating input plus an integrated brazed plate DHW module at 95.0% AFUE, weighing 126 lb with 3.1 gallons of boiler water.
Key figures
- Max input
- 150 MBH
- Max CSA output
- 139 MBH
- AFUE
- 95 %
- Min input
- —
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Weil-McLain ECO Tec 150-C in practice
The 150-C pairs the 150-H's heating ratings — 150 MBH input, 139 MBH DOE heating capacity, 121 MBH net AHRI at 95.0% AFUE — with the built-in DHW module so the same appliance heats the house and makes hot water on demand. It carries the full 10:1 modulation of the ECO Tec line.
At 126 lb it weighs 9 lb more than the heat-only 150-H while sharing the 19 x 20 x 33 inch cabinet, 2.2-to-3.8 gallon water contents by size, and 2" or 3" Category IV venting to 100 ft. The combi's gas connection remains 1/2" NPT and heating water connections 1" NPT.
Best suited to
- Homes needing both heating near 150 MBH and on-demand hot water
- Combi replacements where the previous boiler-plus-tank pair sits at mid-size
- Buyers who want more DHW headroom than the 110-C at the same footprint
Applicability and support
- Model number
- ECO Tec 150-C
- Canadian availability
- available
- Production status
- current
- 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 | 150 MBH | CSA input (maximum). |
| Output | ||
| DOE heating capacity | 139 MBH | DOE heating capacity at maximum input; the manuals also call this CSA Output. |
| Net AHRI water rating | 121 MBH | Net AHRI rating per the boiler manual ratings table. |
| Efficiency | ||
| Efficiency (AFUE) | 95 % | 95.0% AFUE per the boiler manual ratings table. |
| Domestic hot water | ||
| Domestic hot water | Integrated combi: built-in DHW module with brazed plate heat exchanger | |
| Venting and air | ||
| Venting | 2" or 3" PVC, CPVC, polypropylene or AL29-4C stainless steel (Category IV) | Canada: install per CAN/CSA B149.1 or B149.2 with a ULC S636-compliant vent kit. |
| Max. equivalent vent/air length | 100 ft in 2" or 3" (vent and air each) | |
| Physical and connections | ||
| Weight | 126 lb | Boiler weight per the Weil-McLain product spec table. |
| Dimensions (L x W x H) | 19" x 20" x 33" | |
| Gas connection | 1/2" NPT male | |
| Heating water connections | 1" NPT male | Relief valve/air vent connection is 3/4" NPT. |
| Operating limits and other | ||
| Turndown | 10:1 | 10:1 turndown per the CA page and brochure. |
| Boiler water content | 3.1 gal | |
| Altitude rating | 2,000 ft | No modifications from sea level to 2,000 ft; the boiler auto-derates about 4% per 1,000 ft above sea level. |
| Fuel | Natural gas or propane | Propane requires a conversion kit per the CA product page. |
Manuals
- ECO Tec Series 2 Boiler Manual, 550-100-270/0924550-100-270/0924 · 2024-09
Alerts documented for this model
- control-not-receiving-24v-power
- control-not-receiving-120v-power
- display-communication-lost
- TEMP RISE TOO QUICKLY
- Communication errors
- Control fault
- LOW WTR CUTOFF OPEN
- RETURN > SUPPLY
- Boiler Output sensor or Flue sensor
- FLUE TEMP TOO HIGH
- LIMIT OPEN
- HIGH TEMP LIMIT
- FALSE FLAME
- GAS RELAY FAULT 1-4
- IGNITION 1 FAULT
- IGNITION 2 FAULT
- FLAME LOSS FAULT
- AIR PRESSURE Switch Open
- Closure Switch fault
- Configuration fault
- DHW Outlet > Boiler Out
- Internal Clock Fault
- Supply 60F > Return
- Flue 1 Sensor Open
- Flue 1 Sensor Short
- Flue 2 Sensor Open
- Flue 2 Sensor Short
- Boiler Out 1 Sensor Open
- Boiler Out 1 Sensor Short
- Boiler Out 2 Sensor Open
- Boiler Out 2 Sensor Short
- Boiler In Sensor Open
- Boiler In Sensor Short
- Blower Fault 1
- Blower Fault 2
- Blower Fault 3
- Wrong J6 Jumper
- Hardware A2D Fault
- Flame Circuit Fault
- Supply Sensor
- Return Sensor
- DHW Outlet Sensor
- Outdoor Sensor Error
- Exceeded Flow Rate
- Target Reduced - Flue
- Target Reduced - Boiler
- Target Reduced - Flow
- Clock Fault
- Software Incompatible
- Virtual Input Active
- Unconfigured Net 1 or Net 2 Demand
Frequently asked questions
What are the 150-C's ratings?
150 MBH input, 139 MBH DOE heating capacity, 121 MBH net AHRI and 95.0% AFUE — the same heating figures as the heat-only 150-H.
How does the 150-C compare in weight?
It weighs 126 lb, 9 lb more than the 150-H and 12 lb more than the 110-C, all in the same 19 x 20 x 33 inch cabinet.
Does the combi need a separate hot water tank?
No. The brazed plate DHW module produces domestic hot water on demand; a tank is optional for backup rather than required.
Questions about the Weil-McLain ECO Tec 150-C?
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 ECO Tec 110-C vs 150-CComparison
- Weil-McLain ECO Tec 150-C vs 199-CComparison
- Weil-McLain ECO Tec 150-H vs 150-CComparison
- Weil-McLain ECO Tec 80-HSame series
- Weil-McLain ECO Tec 110-HSame series
- Weil-McLain ECO Tec 150-HSame series
- Weil-McLain ECO Tec 199-HSame series
- Weil-McLain ECO Tec 110-CSame series
- Weil-McLain ECO Tec 199-CSame series
- ECO Tec series hub
- Buying guide
Sources and verification
- Weil-McLain Canada — ECO Tec (Combi) · accessed September 7, 2026
- ECO Tec Series 2 Boiler Manual 550-100-270/0924 · 550-100-270/0924 · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.