Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
The legacy Knight KHN199 and KHN285 are the two largest floor-standing fire-tube generations: 20-199 versus 28.5-285 MBH input, 184 versus 264 MBH gross output, both 95% AFUE with 1-1/4" water connections. The 285 adds 80 MBH of gross output and 0.3 gallons more water content.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Lochinvar Knight KHN199 | Lochinvar Knight KHN285 |
|---|---|---|
| Heating input, minimum | 20 MBH | 28.5 MBH |
| Heating input, maximum | 199 MBH | 285 MBH |
| Gross output | 184 MBH | 264 MBH |
| Net AHRI water rating | 160 MBH | 229 MBH |
| Efficiency (AFUE) | 95 % | 95 % |
| Boiler water content | 5.2 gal | 4.9 gal |
| Water connection | 1-1/4" | 1-1/4" |
| Gas connection | 1/2" | 1/2" |
| Vent size | 3" | 3" |
The KH 55-285 I&O ratings table lists the KHN199 at 20-199 MBH input, 184 MBH gross output and a 160 MBH net AHRI rating; the KHN285 lists 28.5-285 MBH input, 264 MBH gross output and a 229 MBH net AHRI rating, both at 95% AFUE.
Both print 3" vent sizes, 1-1/4" water connections and a 1/2" gas connection; water content is 5.2 gallons on the KHN199 and 4.9 gallons on the KHN285 per the table.
The KHN generation is discontinued and documented by the archived Rev J I&O manual; the current floor Knight is the KHB line.
Lochinvar
The Lochinvar Knight KHN199 is a discontinued floor-standing fire-tube boiler rated 20-199 MBH input with 184 MBH gross output and a 160 MBH net AHRI water rating at 95% AFUE.
Lochinvar
The Lochinvar Knight KHN285 is a discontinued floor-standing fire-tube boiler rated 28.5-285 MBH input with 264 MBH gross output and a 229 MBH net AHRI water rating at 95% AFUE.
Capacity: the KHN199 fires 20-199 MBH with 184 MBH gross output and the KHN285 fires 28.5-285 MBH with 264 MBH gross output, both at 95% AFUE.
Lochinvar still hosts the KH 55-285 Installation & Operation Manual (Rev J) from the KHN support pages.
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.