


Hi-Velocity CU-51-EC-H Air Handler
The CU-51-EC-H is a compact CU-51 Cube-series air handler with a backward-curved centrifugal fan and 24 V control board — designed for space-constrained applications such as attics, crawl spaces, garages and single-zone space heating/cooling. Fits 1.5–2 ton of cooling capacity.
Key features
- Compact cube cabinet — installs in Hi-Boy, horizontal or counter-flow positions
- Backward-curved centrifugal fan for consistent static pressure
- Standard 24 V circuit board — prioritizes thermostat calls, controls heating/cooling output and fan speed
- Hydronic coil connections: 3/4" I.D. copper sweat
- Ducted or unducted operation; steam humidifier compatible (18" downstream of supply collar)
- Rear return-air access; single-side service access
- CSA / UL / AHRI / DOE compliant
Specifications
| Model family | Hi-Velocity CU Cube EC Series |
|---|---|
| Configuration | Heating Unit |
| Nominal cooling match | 1.5–2 ton |
| Max BTUH heating @ 190°F EWT | 59,400 BTUH |
| Max BTUH heating @ 160°F EWT | 44,600 BTUH |
| Chilled-water cooling | WBM/WCM-50 (up to 25,800 BTUH @ 40°F total) |
| Hydronic connections | 3/4" I.D. copper sweat |
| Outlet minimum | 6 HE or 12 2" per ton |
| Shipping weight | 49 lbs |
| Shipping dimensions | 20"x20"x18" |
Applications
The Cube Series suits attic and crawl-space installations, garage heaters, single-room add-ons and other space-constrained retrofit jobs — anywhere a full HE-Z or LV cabinet won't fit but rear-return, high-static-pressure air delivery is still required.
Documents
- Cube EC Installation Manual (PDF)
- HE-Z Standard Brochure (PDF)
- HE-Z Engineering Specifications (PDF)
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Hi-Velocity CU-51-EC-H Air Handler
Sale price$2,875.00 USD