Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
The GV90+5 is the first GV90+ to move to the long 37-3/4" cabinet: input steps from 105 to 140 MBH and DOE heating capacity from 97 to 130 MBH at a slightly higher 91.4% AFUE, with water content up from 4.7 to 6.0 gallons.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Weil-McLain GV90+4 | Weil-McLain GV90+5 |
|---|---|---|
| Input, maximum | 105 MBH | 140 MBH |
| DOE heating capacity | 97 MBH | 130 MBH |
| Net AHRI water rating | 84 MBH | 113 MBH |
| Efficiency (AFUE) | 91.2 % | 91.4 % |
| Weight | 353 lb | 423 lb |
| Boiler water content | 4.7 gal | 6 gal |
| Venting | 3" PVC, CPVC, polypropylene or stainless steel (Category IV); 3" pipe on all GV90+ sizes | 3" PVC, CPVC, polypropylene or stainless steel (Category IV); 3" pipe on all GV90+ sizes |
Both are Series 2 GV90+ units with the built-in low water cut-off, 3" venting to 100 ft, 1" NPT supply and return connections and 1/2" NPT gas. The +5 steps input from 105 to 140 MBH, DOE heating capacity from 97 to 130 MBH and the net AHRI rating from 84 to 113 MBH.
The +5 is also the first size in the longer 37-3/4" cabinet, holding 6.0 gallons against 4.7 and shipping at 423 lb against 353 lb — a meaningful footprint and handling difference for a basement mechanical room.
Efficiency is nearly flat across the step — 91.4% AFUE on the +5 against 91.2% on the +4 — so the decision is capacity and cabinet size, driven by the heat-loss calculation and the boiler room's dimensions.
Weil-McLain
The GV90+4 steps the cast iron line to 105 MBH input and 97 MBH DOE heating capacity at 91.2% AFUE, keeping the 30-3/4" cabinet length with 4.7 gallons of boiler water.
Weil-McLain
The GV90+5 is the first of the long-cabinet GV90+ sizes: 140 MBH input, 130 MBH DOE heating capacity and a 113 MBH net AHRI rating at 91.4% AFUE, in a 37-3/4" unit.
Its cabinet runs 37-3/4" long against 30-3/4" on the +4, and it ships at 423 lb against 353 lb with 6.0 gallons of water.
140 MBH input, 130 MBH DOE heating capacity, 113 MBH net AHRI and 91.4% AFUE.
Yes — 3" Category IV pipe to 100 ft, with 1" NPT supply and return connections.
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.