Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
Boilers.ca is a brand of ROMA Heating & Cooling · Licensed gas contractor LGA0202903
Comparison
Verdict in brief
Utica MAC-115 and Utica MAC-205 are two combination (combi) boilers from the Utica Boilers MAC/MAH (AI condensing) line. Published ratings: Utica MAC-115 at 16.6–93.5 MBH input and 95% AFUE; Utica MAC-205 at 29.5–164 MBH input and 95% AFUE. Utica MAC-205 lists 70.5 MBH more input than Utica MAC-115 (164 MBH against 93.5 MBH). Both list the same published AFUE of 95%. Both list the same published shipping weight (94-125 lb).
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Utica MAC-115 | Utica MAC-205 |
|---|---|---|
| Central-heating input, minimum | 16.6 MBH | 29.5 MBH |
| Central-heating input, maximum | 93.5 MBH | 164 MBH |
| AFUE | 95 % | 95 % |
| Weight | 94-125 lb | 94-125 lb |
| Dimensions (H x W x D) | 30" x 17-3/4", depth 13-9/16" or 21-1/2" | 30" x 17-3/4", depth 13-9/16" or 21-1/2" |
| Venting | Coaxial polypropylene or 2-pipe polypropylene/CPVC/PVC | Coaxial polypropylene or 2-pipe polypropylene/CPVC/PVC |
| DHW flow rate at 70 °F rise | 2.5 gpm | 5 gpm |
| Turndown, heating mode | 5.6:1 | 5.5:1 |
| Turndown, DHW mode | 6.9:1 | 7:1 |
| Heat exchanger | 316L stainless steel heat exchanger and burner plus stainless steel brazed-plate DHW heat exchanger | 316L stainless steel heat exchanger and burner plus stainless steel brazed-plate DHW heat exchanger |
| Gas type | Natural gas or LP — recognized automatically | Natural gas or LP — recognized automatically |
Published ratings: the Utica MAC-115 is rated 16.6–93.5 MBH input and 95% AFUE; the Utica MAC-205 is rated 29.5–164 MBH input and 95% AFUE. Utica MAC-205 lists 70.5 MBH more input than Utica MAC-115 (164 MBH against 93.5 MBH). Both list the same published AFUE of 95%.
The dhw flow rate at 70 °F rise differs: the Utica MAC-115 lists 2.5 gpm, while the Utica MAC-205 lists 5 gpm. The turndown, heating mode differs: the Utica MAC-115 lists 5.6:1, while the Utica MAC-205 lists 5.5:1. The turndown, dhw mode differs: the Utica MAC-115 lists 6.9:1, while the Utica MAC-205 lists 7:1.
Both records print the same AFUE (95%), shipping weight (94-125 lb), dimensions (30" x 17-3/4", depth 13-9/16" or 21-1/2") and venting (Coaxial polypropylene or 2-pipe polypropylene/CPVC/PVC), per the cited sources.
Utica Boilers
The Utica MAC-115 is the 115-class (smallest) combi combi of the MAC 'AI' condensing line: 95% AFUE, on-demand DHW at 2.5 GPM (70 °F rise), 5.6:1 heating turndown and the 316L stainless steel heat exchanger. The MAC page prints '(While supplies last)' with no current documents, so this model is discontinued (sell-through).
Utica Boilers
The Utica MAC-205 is the 205-class (largest) combi combi of the MAC 'AI' condensing line: 95% AFUE, on-demand DHW at 5 GPM (70 °F rise), 5.5:1 heating turndown and the 316L stainless steel heat exchanger. The MAC page prints '(While supplies last)' with no current documents, so this model is discontinued (sell-through).
The Utica MAC-205 lists 164 MBH, against 93.5 MBH on the Utica MAC-115, per the cited documentation.
Both list the same AFUE of 95%.
A consultation includes a heat-loss review so the size is right the first time.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.
Sources and verification
Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.