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Find Your Replacement

Your G521226G051 has an adapter-fit replacement.

Same capacity, same voltage. The included adapter plate bridges your existing cutout to the AT12RNSXX — fitting work during the swap, not a new cutout.

Also sold as McLean · Hoffman · Pentair · nVent — G521226G051 — 12,000 BTU/hr · 230V · NEMA 4X · R-134A

G521226G051

Yours

G521226G051

Adapter fit
VoltAire AT12RNSXX — replacement for G521226G051

Ours, in production

VoltAire AT12RNSXX

43.99″ H × 12.30″ D × 16.39″ W · 96.9 lbs

Adapter Fit · +$405 Fit details ↓

You'll order: 1× AT12RNSXX + 1× adapter plate — $6,775 total.

Verified fit path — so you're not the one explaining a wrong-fit order.

Where distributors publish pricing for the nVent equivalent, VoltAire runs 48% less on average — 21–70% by model (sourced July 2026).

Your Replacement

AT12RNSXX

Adapter Fit

12,000 BTU/hr • 230V • NEMA 4X

Availability Built to Order 4-6 weeks — made in Orlando, FL
Includes Unit + adapter plate 30-day price lock · no-obligation quote
Built Orlando, FL — UL/cUL Listed

Need It Faster?

The AT12RNW10 is on the shelf right now — same 12,000 BTU/hr, same 230V, with a 1,000W electric heater included and in the standard off-white cabinet. It ships next business day instead of 4-6 weeks — and it costs $1,699 less.

Take the in-stock AT12RNW10 $5,076

Your order total

$6,775

Adapter plate included in this price.

Start My Order

Backed by VoltAire’s 12-month warranty (PDF) · UL 484 · Made in Orlando, FL

Existing Unit

G521226G051

12,000 BTU/hr (3,517 Watt) • 230V
G521226G051
Brand McLean
Series G5212
Capacity 12,000 BTU/hr (3,517 Watt)
Voltage 230V
Heat No
Finish S

Where distributors publish pricing for the OEM equivalent, VoltAire runs 48% less on average (21-70% by model).

VoltAire Replacement In Production
AT12RNSXX
12,000 BTU/hr • 230V
VoltAire AT12RNSXX
Brand VoltAire
Series AT Telecom Series
Capacity 12,000 BTU/hr
Voltage 230V
Heat No
Finish 304 Stainless Steel (NEMA 4X)

What You'll Order

1× AT12RNSXX $6,370
1× Adapter / Transition Plate $405
Order total $6,775

Popular options

Screens sawdust, filings & insects off the condenser coil — not an enclosure air filter; cabinet air stays sealed.

Need a different voltage or capacity? Configure your AT08 / AT10 / AT12 →

Built to Order • 4-6 weeks

1

Super Cool Coverage — 2 years of coverage, 30-day returns, no restocking fee. Terms

Details

Fit Details

Adapter Fit

Same cooling capacity and voltage as the G521226G051. Cabinet cutout dimensions differ, so an adapter plate is required to bridge the mounting pattern between the existing opening and the VoltAire AT12RNSXX — so you're not fabricating a new opening. Plan on some fitting work during the swap; we'll spec the exact adapter for your installation at order review.

Not sure? Talk to a fit specialist — (844) 925-5668.

G521226G051 replacement — common questions

What replaces the McLean G521226G051?
The VoltAire AT12RNSXX — 12,000 BTU/hr at 230V, NEMA 4X, UL/cUL Listed and built in Orlando, FL. Adapter fit — mounts to your existing cutout with the included adapter plate.

Will the VoltAire AT12RNSXX fit my G521226G051 cutout?
Yes, with the adapter plate included in the quoted total. It bridges your existing G521226G051 cutout to the AT12RNSXX mounting pattern so you're not fabricating a new opening — but plan on some fitting work during the swap. The dimensions table on this page compares both units side by side; if anything looks off for your cabinet, call (844) 925-5668 before you order.

How much does a G521226G051 replacement cost?
The VoltAire AT12RNSXX is $6,775 including the adapter plate. Where distributors publish pricing for the nVent equivalent, VoltAire runs 48% less on average — 21–70% by model (sourced July 2026). Volume discounts start at 4 units, and every quote locks pricing for 30 days with no obligation.

How fast can I get a replacement for my G521226G051?
Configured builds ship in 4–6 weeks from Orlando, FL. In-stock variants are sometimes on the shelf — call (844) 925-5668 and we'll find the fastest path for your spec.

Is the VoltAire AT12RNSXX an original McLean part?
No. VoltAire is an independent brand — an engineered replacement, not an OEM part. VoltAire Cooling is not affiliated with McLean, Hoffman, Pentair, or nVent. Units are UL/cUL Listed (UL 484) and manufactured in Orlando, Florida.

Why switch to VoltAire?

Engineered Replacement

Same capacity, same voltage, NEMA 4 protection — with a clear fit path for your enclosure: direct, adapter plate, or template-guided modification. Built to replace McLean, Hoffman, Pentair, and nVent.

Built & Tested in the USA

Manufactured in Orlando, FL with a 5-point pressure and leak test. In-stock models ship fast from East Coast (VA) and Rocky Mountain (ID) warehouses; built-to-order configurations ship in 4-6 weeks.

48% Below Published Online Pricing, on Average

No distribution markup. Transparent pricing. Volume discounts at 4+ and 7+ units. Integrator pricing available for panel shops.

Need heat, stainless, 230V, or remote monitoring?

The AT08 is available with electric heat, stainless steel NEMA 4X, 48VDC, and factory ethernet controllers with Lead-Lag, SNMP, and BACnet.

Configure Your AT08 / AT10 / AT12 →

Related models

G521226G051 (this page) G521226G101 G521226G700 G521226G100 G521226G800 G521226G060 G521226G802 G521226G050 G521226G102 G521226G150 G521226G360 G521226G151

VoltAire Cooling is an independent party and is not affiliated with or endorsed by McLean, Hoffman, Pentair, or nVent. All competitor brand names and model numbers are the property of their respective owners and are used here for identification and compatibility purposes only.