Kramer 3.5 HP Medium Temperature Walk-In Cooler Refrigeration System
The Kramer KFO350E4SDA outdoor condensing unit and KL6A235ADASC low profile unit cooler form a factory-matched 3.5 HP medium temperature refrigeration package for large walk-in coolers up to roughly 20 ft × 32 ft. It uses the same four-fan KL6A235 coil as the 3 HP package but pairs it with a larger ZS26KAE scroll compressor, so it covers the same room footprint with more capacity in reserve. Configured for R448A or R449A refrigerant, it suits demanding grocery distribution, high-traffic cold rooms, and central commissary applications.
Is a 3.5 HP Refrigeration System the Right Size?
This package is matched to medium temperature coolers up to about 20 ft × 32 ft holding 35°F to 38°F — the same footprint as the 3 HP KFO300 — but it does so with additional headroom. At 25°F suction on R448A or R449A the KFO350E4SDA produces 29,760 BTUH at a 95°F ambient, with a matched system rating near 29,468 BTUH at 25°F SST.
Because the larger ZS26KAE compressor carries more capacity behind the same KL6A235 coil, this package is the better choice when a 20 ft × 32 ft room runs in a hot outdoor ambient, sees constant dock-door traffic, or must pull down quickly after large warm loads — it still delivers 25,710 BTUH at a 110°F ambient. For a similar room with lighter use, the 3 HP KFO300 covers the same sizes at lower cost.
Ideal for: high-volume grocery and food distribution, busy cold rooms with heavy door traffic, central commissary kitchens, and cold storage in hot climates.
Representative box sizes: this package is commonly applied to coolers such as 20 ft × 24 ft, 20 ft × 28 ft, and 20 ft × 32 ft, with more reserve capacity than the 3 HP package at the same box sizes.
Need more capacity? Step up to the Kramer 4 HP KFO400E4SDA Refrigeration System (dual coil). For a smaller room, see the Kramer 3 HP KFO300E4SDA & KL6A235ADASC system.
Recommended refrigeration applications are general guidelines only. Actual system requirements depend on insulation, ambient conditions, door openings, product load, and operating temperature. Request free sizing assistance, contact Budget Heating, or call 813-885-7999.
What's Included
| Outdoor Condensing Unit | KFO350E4SDA — 3.5 HP Medium Temperature Condensing Unit |
|---|---|
| Indoor Evaporator | KL6A235ADASC Low Profile Unit Cooler |
| Application | Medium Temperature Walk-In Cooler Refrigeration System |
| System Capacity | Approximately 29,468 BTUH matched system (R448A/R449A, 25°F S.T., 10.6°F TD) |
| Refrigerant | R448A or R449A |
| Compressor | High-Efficiency Scroll Compressor |
| Evaporator Defrost | Air Defrost |
| Electrical | 208-230V, Single Phase, 60 Hz Condensing Unit |
| Evaporator Electrical | 115V |
| Factory Charge | Nitrogen Holding Charge — Refrigerant Field Supplied |
| Manufacturer Warranty | 1 Year |
The KFO350E4SDA condensing unit and the KL6A235ADASC low profile evaporator are also stocked individually for replacement work. Ordering them together as this matched package keeps the condensing unit and coil capacities aligned at design conditions. All units ship under a nitrogen holding charge, so plan on field-supplied R-448A or R-449A refrigerant and evacuation, charging, and commissioning by an EPA 608 certified technician.
Condensing Unit & Evaporator Features
KFO350E4SDA Outdoor Condensing Unit
- 3.5 HP ZS26KAE scroll compressor for medium temperature commercial refrigeration
- 29,760 BTUH at 95°F ambient and 25°F suction on R448A or R449A
- 25,710 BTUH still available at 110°F ambient and 25°F suction for rooftop and unshaded slab installations
- Integral liquid sub-cooling circuit providing an average 3°F to 5°F of sub-cooling for improved efficiency and stable expansion valve operation
- Flooded head pressure control standard, supporting operation as outdoor ambient temperatures drop
- Generously sized condenser coil with enhanced copper tubes and aluminum fins in an all-weather painted galvanized steel housing
- Ships under a nitrogen holding charge, with a refrigerant receiver, isolation valve, and pressure relief plug
- Liquid line with sealed filter and sight glass, factory crankcase heater, and electronic air defrost timer
- Fixed high-pressure and adjustable low-pressure controls, with quick-access shut-off valves and color-coded point-to-point wiring
- 208-230V single phase draw of 21.2 rated load amps and 104 locked rotor amps, on a 32.7 amp minimum circuit ampacity with 50 amp maximum overcurrent protection
KL6A235ADASC Low Profile Unit Cooler
- 27,800 BTUH with R448A or R449A at 25°F SST and 10°F TD, and 23,500 BTUH on R404A
- Multi-circuit coil fed by a refrigerant distributor for even refrigerant distribution across the coil face
- Factory-mounted thermostatic expansion valve, selected for R448A and R449A service
- Four balanced aluminum fans moving 3,140 CFM through a draw-through air pattern
- Dual-speed electronically commutated 115V motors with thermal overload protection, compliant with California Title 24
- 6 fins-per-inch coil using 3/8 in. enhanced copper tubes mechanically expanded into corrugated aluminum fins with die-formed collars
- Air defrost configuration intended for coolers held at 35°F and warmer, factory wired to screw-type terminal strips
- Embossed aluminum casing with baffled fan sections, NSF compliant and designed to mount flush to the ceiling
- Removable 3/4-14 NPT drain fitting at the bottom of the pan, replaceable without changing the pan
- 3/8 in. liquid and 5/8 in. suction connections, UL and cUL listed
Specifications & Manuals
Product documentation includes technical specifications, installation information, maintenance instructions, warranty information, and KL6 Series literature to assist with equipment selection, installation, and service. This system carries a 1 year manufacturer warranty; see the Kramer warranty documentation above for full coverage terms and conditions.
Frequently Asked Questions
What size walk-in cooler is the KFO350E4SDA matched to?
Large medium-temperature coolers up to about 20 ft × 32 ft holding 35°F to 38°F — the same footprint as the 3 HP package, but with more capacity behind it.
How is the KFO350E4SDA different from the 3 HP KFO300E4SDA?
Both use the same four-fan KL6A235 coil and cover the same room sizes. The KFO350E4SDA steps up to a larger ZS26KAE compressor, raising capacity from about 28,078 to 29,468 BTUH at 25°F SST.
If they cover the same box size, why choose the 3.5 HP over the 3 HP?
The extra compressor capacity is the right call when a 20 ft × 32 ft room runs in a hot outdoor ambient, sees constant dock-door traffic, or must recover quickly after large warm loads. For a similar room with lighter use, the 3 HP KFO300 covers the same sizes at lower cost.
How hot an ambient can the condensing unit tolerate?
It is outdoor-rated and still delivers about 25,710 BTUH at a 110°F ambient, which is a large part of why it is preferred over the 3 HP for hot-climate installations.
Who should commission a system this size?
An EPA 608 certified refrigeration technician. It ships under a nitrogen holding charge and must be evacuated, charged with R-448A or R-449A, and started up to the manufacturer's procedure.
What warranty is included?
The system carries a 1 year Kramer/HTPG limited warranty on materials and workmanship; components not made by HTPG, such as the compressor, carry their manufacturer's warranty. See the warranty document above.
Kramer KFO Condenser Technical SpecificationsKramer Installation GuideKramer Maintenence ManualKramer KL6 Technical SpecificationsKramer KL6 CatalogKramer Warranty
