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Lochinvar · Copper-Fin (CBN/CHN)

Lochinvar Copper-Fin II CHN0752

The Copper-Fin II CHN0752 reaches 250 to 750 MBH input with 638 MBH gross output and a 555 MBH AHRI net rating at 85% thermal efficiency, closing the 2" water-connection group.

CurrentSold in Canada
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Key figures

Max input
750 MBH
Max CSA output
—
AFUE
—
Min input
250 MBH
Natural gasPropaneHeating-onlycommercial

Input is gas energy consumed; output is heat delivered. Never size from input alone.

Lochinvar Copper-Fin II CHN0752 in practice

The CHN0752 is the largest Copper-Fin II size on 2" NPT water connections (6-1/2" centers) and a 1-1/4" gas connection: 250 to 750 MBH input, 638 MBH gross output and a 555 MBH AHRI net water rating at 85% thermal efficiency, with 2.4 gallons of water content. The CHE-Sub-11 submittal prints a 543 lb shipping weight and 8" vent and air-inlet sizes.

The cabinet keeps the 31-1/2" A / 22-1/4" C dimensions with a 64" B dimension. It carries the full Copper-Fin II feature set — SMART SYSTEM control with 8-boiler cascade, front-end loading with Crest or Knight, proportional firing up to 4:1, BMS integration, Category I/IV venting — at 85% AHRI-certified thermal efficiency, with a 10-year limited warranty and 1-year parts in the submittal.

Best suited to

  • Loads near 750 MBH on 2" water piping
  • The last Copper-Fin II size before the connection group changes
  • Cascades that want 4:1 proportional firing at the 750 MBH scale

Applicability and support

Model number
CHN0752
Canadian availability
available
Production status
current
ROMA supplies
Confirmed at consultation
ROMA services
Confirmed at consultation
Warranty
Series terms

Where ROMA provides on-site service

On-site service is currently offered in Greater Vancouver, BC, including Vancouver, Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, West Vancouver, New Westminster, Port Coquitlam, Port Moody, Delta, Langley, Maple Ridge, Abbotsford, Chilliwack, White Rock, Pitt Meadows, Tsawwassen, Anmore, Lions Bay, Belcarra, Bowen Island, Mission. Everything else on this site is reference information you can use anywhere in Canada.

See all service areas

Specifications

Published specifications

Values as published by Lochinvar. Units are shown with every value; notes flag conflicting sources or missing figures.

Lochinvar Copper-Fin II CHN0752 specifications
SpecificationValueNote
Input
Heating input, minimum250 MBHPer the I&O ratings table.
Heating input, maximum750 MBHPer the submittal sheet and the I&O ratings table.
Output
Gross output638 MBHGross output per the submittal sheet ratings table.
Net AHRI water rating555 MBHNet AHRI rating based on a piping and pickup allowance of 1.15, per the submittal and I&O ratings-table notes.
Efficiency
Efficiency (thermal)85 %85% thermal efficiency (AHRI certified) printed in the CHE-Sub-11 submittal and on the product page; no AFUE is published.
Venting and air
Vent size8"Per the submittal and I&O ratings tables.
Air inlet size8"Per the CHE-Sub-11 submittal ratings table.
VentingCategory I (Type B double-wall) or Category IV (AL29-4C stainless steel); vertical or horizontalPer the CHE-Sub-11 standard features and the CHX I&O venting section; DirectAire and powered sidewall options are listed in the submittal.
Physical and connections
Water content2.4 galPer the I&O ratings table.
Space-heating water connections2"2" NPT on 6-1/2" centers per the CHE-Sub-11 submittal.
Gas connection1-1/4"Per the submittal and I&O ratings tables.
Shipping weight543 lbShipping weight per the submittal sheet ratings table.
Dimension A31-1/2"As labeled on the CHE-Sub-11 dimension drawing; dimensions are approximate per the submittal.
Dimension B64"As labeled on the CHE-Sub-11 dimension drawing; dimensions are approximate per the submittal.
Dimension C22-1/4"As labeled on the CHE-Sub-11 dimension drawing; dimensions are approximate per the submittal.
Dimension D12-1/2"As labeled on the CHE-Sub-11 dimension drawing; dimensions are approximate per the submittal.
Dimension E8-1/2"As labeled on the CHE-Sub-11 dimension drawing; dimensions are approximate per the submittal.
Dimension F8-1/4"As labeled on the CHE-Sub-11 dimension drawing; dimensions are approximate per the submittal.
Dimension G29"As labeled on the CHE-Sub-11 dimension drawing; dimensions are approximate per the submittal.
Dimension H6-1/2"As labeled on the CHE-Sub-11 dimension drawing; dimensions are approximate per the submittal.
Operating limits and other
FiringProportional, up to 4:1 turndownProportional firing up to 4:1 turndown per the CHE-Sub-11 standard features; the CHX I&O ratings table prints minimum inputs of 250/360/630 MBH by size.

Manuals

    Alerts documented for this model

    None documented yet.

    Services

    Related parts & service

    Frequently asked questions

    What are the CHN0752's ratings?

    250 to 750 MBH input, 638 MBH gross output and a 555 MBH AHRI net water rating at 85% thermal efficiency, per the CHE-Sub-11 submittal and the CHX I&O ratings table.

    What connections does the CHN0752 use?

    2" NPT water connections on 6-1/2" centers and a 1-1/4" gas connection, with 8" vent and air-inlet sizes per the CHE-Sub-11 submittal.

    Questions about the Lochinvar Copper-Fin II CHN0752?

    Describe what the boiler is doing and get a straight answer about the next step.

    On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.

    Call 778-909-5731Request service

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    Sources and verification

    Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.

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