De Dietrich MCA Pro 45
The De Dietrich MCA Pro 45 is a condensing wall-hung boiler rated 34–156 MBH input and 33–146 MBH output at 94.0% CSA thermal efficiency, with 1-1/4" heating connections and a 117 lb dry weight.
Key figures
- Max input
- 156 MBH
- Max CSA output
- 146 MBH
- AFUE
- —
- Min input
- 34 MBH
Input is gas energy consumed; output is heat delivered. Never size from input alone.
De Dietrich MCA Pro 45 in practice
The MCA Pro 45 is the 45 kW size of De Dietrich's North American condensing wall-hung line, documented in the MCA Pro submittal Rv 5.4 and specification data. It prints 34–156 MBH input, 33–146 MBH output, 94.0% CSA thermal efficiency (94.3% combustion), usable efficiency up to 98.2% and standby loss below 0.3%.
The boiler uses a cast-aluminum heat exchanger, fires natural gas or propane with modulating, on/off or remote 0–10 V control, and connects to the heating circuit through 1-1/4" male NPT supply and return pipes with a 3/4" male NPT gas connection. Venting is 3" single pipe / 80–125 mm concentric. The MCA Pro page notes cascade configurations of 2 to 8 boilers, and DDR Americas (Cambridge, Ontario) is the North American supplier.
Best suited to
- Residential and light-commercial loads from 33 to 146 MBH output
- Wall-hung installations that need a compact condensing boiler with a cast-aluminum heat exchanger
- Cascade plants of 2 to 8 boilers (page copy)
Applicability and support
- Model number
- MCA Pro 45
- Canadian availability
- available
- Production status
- current
- 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 De Dietrich. Units are shown with every value; notes flag conflicting sources or missing figures.
| Specification | Value | Note |
|---|---|---|
| Input | ||
| Minimum input (as printed) | 34 MBH | Printed in the MCA Pro submittal technical specifications; the source row is labelled 'Minimum Fuel Input'. |
| Maximum input (as printed) | 156 MBH | Printed in the MCA Pro submittal; the source repeats the label 'Minimum Fuel Input' for this row — by context (model kW rating and the min/max output pair) it is the maximum. Kept verbatim with this note. |
| Output | ||
| Minimum heat output | 33 MBH | Printed in the MCA Pro submittal. |
| Maximum heat output | 146 MBH | Printed in the MCA Pro submittal. |
| Efficiency | ||
| Thermal efficiency (CSA certified) | 94 % | Printed in the MCA Pro submittal; combustion efficiency 94.3% CSA certified, usable efficiency up to 98.2%, standby loss < 0.3%. |
| Venting and air | ||
| Vent / combustion air | 3" single pipe / 80–125 mm concentric | Printed in the MCA Pro submittal dimensions notes; gas vent category IV-BH per ANSI Z21.13a / CSA 4.9. |
| Physical and connections | ||
| Heating supply / return | 1-1/4" male NPT | Printed in the MCA Pro submittal dimensions notes. |
| Gas connection | 3/4" male NPT | Printed in the MCA Pro submittal dimensions notes. |
| Weight (dry / wetted) | 117 lb dry / 130 lb wetted | Printed in the MCA Pro submittal. |
| Operating limits and other | ||
| Firing | Modulating, on/off, remote 0–10 V | Printed in the MCA Pro submittal; modulation range 20–100% per the international page. |
| Operating water temperature range | 68–190 °F (CPVC / PP / SS) | Printed in the MCA Pro submittal; max safety limit 230 °F, water pressure 12–56 psig. |
| CSA certified installation altitude | Max 4,500 ft / 1,370 m (Canada) | Printed in the MCA Pro submittal. |
| Fuel | Natural gas or propane (LPG) | Printed in the MCA Pro submittal gas and venting data. |
Manuals
Alerts documented for this model
Frequently asked questions
What is the input range of the MCA Pro 45?
The MCA Pro submittal prints 34–156 MBH input and 33–146 MBH output for this size, at 94.0% CSA thermal efficiency.
What connections does the MCA Pro 45 use?
The submittal prints 1-1/4" male NPT heating supply and return connections, a 3/4" male NPT gas connection, and 3" single pipe / 80–125 mm concentric venting.
Can MCA Pro boilers be cascaded?
Yes — the product page states cascade configurations of 2 to 8 boilers are standard, with any configuration possible.
Questions about the De Dietrich MCA Pro 45?
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
- De Dietrich NA — MCA Pro Series product page · accessed September 9, 2026
- DDR Americas — Cambridge, Ontario company page · accessed September 9, 2026
- De Dietrich — MCA Pro engineering submittal Rv.5.4 (technical specifications) · accessed September 9, 2026
- De Dietrich — MCA Pro Specification Data · accessed September 9, 2026
Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.