Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
The XVers L H7-506L adds 101 MBTUH of input and 98 MBTUH of output over the XVers L H7-406L on the same XVers L platform. The 406L and 506L are the two 10:1-turndown sizes in the range, and the 506L's extra 101 MBTUH of input keeps the same 2 in water connections and 73 gpm maximum flow.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Raypak XVers L H7-406L | Raypak XVers L H7-506L |
|---|---|---|
| Input | 399 MBH | 500 MBH |
| Output | 391 MBH | 489 MBH |
| AHRI thermal efficiency | 98 % | 97.8 % |
| Turndown | 10:1 | 10:1 |
| Water connection | 2" NPT | 2" NPT |
| Weight | 547 lb | 611 lb |
| Maximum water flow | 73 GPM | 73 GPM |
The H7-406L is rated 399 MBTUH input and 391 MBTUH output with 10:1 turndown; the H7-506L is rated 500 MBTUH input and 489 MBTUH output with 10:1 turndown. H7-406L is rated 98% and H7-506L 97.8% in the same efficiency column, so the larger size does not give up rated efficiency.
The 406L and 506L are the two 10:1-turndown sizes in the range, and the 506L's extra 101 MBTUH of input keeps the same 2 in water connections and 73 gpm maximum flow. Both share the same 73 gpm maximum water flow, so the step up does not enlarge the pump or piping envelope. Shipping or operating weight moves from 547 lb to 611 lb, which matters for rigging and floor loading.
Both sizes are documented in the same official Raypak submittal for the XVers L family, so the decision is a heat-loss and plant-layout question rather than a documentation difference: size to the calculated design-day load, then check flow, connection and venting dimensions against the submittal for the exact model.
Raypak
The Raypak XVers L H7-406L is a condensing firetube commercial hydronic boiler rated 399 MBTUH input and 391 MBTUH output at 98% AHRI thermal efficiency, with 10:1 turndown, Category IV venting and a maximum water flow of 73 gpm per the 241896 submittal.
Raypak
The Raypak XVers L H7-506L is a condensing firetube commercial hydronic boiler rated 500 MBTUH input and 489 MBTUH output at 97.8% AHRI thermal efficiency, with 10:1 turndown, Category IV venting and a maximum water flow of 73 gpm per the 241896 submittal.
Yes — both use a 4 in flue and 4 in combustion-air intake and are Category IV condensing appliances per submittal 241896.
The 406L fires down to a lower minimum and matches small loads; choose the 506L only when the calculated load approaches or exceeds the 406L's output.
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.