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
The Noble NKC150 and NKC199 are the two largest wall-hung Noble combis and share their 1" NPT and 3/4" DHW connections and 95.0% AFUE rating. The 199 fires 19.9 to 199 MBH with 185 MBH of DOE capacity against the 150's 139, holds 2.7 gallons against 2.0, and its 2" vent allowance drops from 60 to 50 equivalent feet.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Lochinvar Noble NKC150 | Lochinvar Noble NKC199 |
|---|---|---|
| Heating input, minimum | 15 MBH | 19.9 MBH |
| Heating input, maximum | 150 MBH | 199 MBH |
| DOE heating capacity | 139 MBH | 185 MBH |
| AHRI net water rating | 121 MBH | 161 MBH |
| Efficiency (AFUE) | 95 % | 95 % |
| Water content | 2 gal | 2.7 gal |
| Space-heating water connections | 1" NPT | 1" NPT |
| DHW water connections | 3/4" | 3/4" |
| Gas connection | 1/2" | 1/2" |
| Max. equivalent vent/air length, 2" | 60 ft | 50 ft |
| Max. equivalent vent/air length, 3" | 100 ft | 100 ft |
| Domestic hot water | On demand from the combi's DHW circuit | On demand from the combi's DHW circuit |
Both are wall-mounted Noble combis with on-demand domestic hot water through 3/4" DHW connections, 1" NPT space-heating connections and a 1/2" gas connection, sold as Epic in Canada on Lochinvar's residential page.
The 199 carries the largest combi ratings in the family: 19.9 to 199 MBH of input with 185 MBH of DOE capacity and a 161 MBH AHRI net rating. Its 19.9 MBH minimum fire is well above the 150's 15 MBH, so buildings whose load stays under 150 MBH are better served by the smaller model.
Venting is the deciding installation factor: the 150 reaches 60 equivalent feet in 2" pipe and the 199 only 50, while 3" venting to 100 feet serves both. Any long or elbow-heavy route points to 3" pipe on either model.
Lochinvar
The Noble NKC150 is the 150 MBH Noble wall-hung combi: 15 to 150 MBH space-heating input at 95.0% AFUE with 139 MBH DOE capacity and a 2-gallon water content.
Lochinvar
The Noble NKC199 is the top Noble wall-hung combi: 19.9 to 199 MBH space-heating input at 95.0% AFUE with 185 MBH DOE capacity, DHW on demand through 3/4" connections.
Input rises from 15-150 MBH to 19.9-199 MBH, DOE capacity from 139 to 185 MBH and water content from 2.0 to 2.7 gallons; connections and the 3" vent allowance are unchanged.
For most houses, yes — its 19.9 MBH minimum fire is a large part-load. It suits large homes and small multi-suite buildings whose heat-loss calculation approaches 199 MBH.
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 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.