Kramer 4 HP Low Temperature Walk-In Freezer Refrigeration System
The Kramer KFO400L4SDB outdoor condensing unit and KL6E105DDASC low profile unit cooler form a factory-matched 4 HP low-temperature refrigeration package for walk-in freezers up to roughly 12 ft × 18 ft. A ZF13K4E low-temperature scroll compressor is paired with a two-fan electric-defrost evaporator, delivering about 12,990 BTUH at 95°F ambient and a -20°F saturated suction to hold a freezer near a -10°F box temperature on R448A or R449A refrigerant. It suits large frozen-storage and distribution freezers and processing operations.
Is a 4 HP Low-Temp Freezer System the Right Size?
This package is matched to walk-in freezers up to about 12 ft × 18 ft holding a -10°F box. Its rated system capacity is near 12,896 BTUH at a -20°F saturated suction temperature. Because a freezer at -10°F carries a much higher heat load than a cooler of the same footprint, a freezer system covers a smaller box than a cooler of similar horsepower — size from a calculated freezer load rather than floor area.
Freezer load is driven by insulation R-value, outdoor ambient, door-opening frequency, the quantity and entering temperature of product frozen or stored each day, defrost frequency, and required pull-down time. Heavy door traffic or large daily product loading raises the requirement, so high-use freezers should size down a step. The matched KL6E105DDASC evaporator uses timed electric defrost, which is required below freezing because off-cycle air cannot clear coil frost.
Ideal for: large frozen-storage and distribution freezers and processing operations.
Need more capacity? Step up to the Kramer 5 HP KFO500L4SDB Walk-In Freezer System. For a smaller freezer, see the Kramer 3.5 HP KFO350L4SDA Walk-In Freezer System.
Recommended refrigeration applications are general guidelines only. Actual system requirements depend on insulation, ambient conditions, door openings, product load, defrost, and operating temperature. Request free sizing assistance, contact Budget Heating, or call 813-885-7999.
What's Included
| Outdoor Condensing Unit | KFO400L4SDB — 4 HP Low Temperature Condensing Unit |
|---|---|
| Indoor Evaporator | KL6E105DDASC Low Profile Electric-Defrost Unit Cooler |
| Application | Low Temperature Walk-In Freezer Refrigeration System |
| System Capacity | Approximately 12,896 BTUH (R448A/R449A, -20°F SST) |
| Refrigerant | R448A or R449A |
| Compressor | High-Efficiency Low-Temperature Scroll Compressor |
| Evaporator Defrost | Electric Defrost (2,250 W) |
| Electrical | 208-230V, Single Phase, 60 Hz Condensing Unit |
| Evaporator Electrical | 208-230V |
| Factory Charge | Nitrogen Holding Charge — Refrigerant Field Supplied |
| Manufacturer Warranty | 1 Year |
The KFO400L4SDB condensing unit and the KL6E105DDASC evaporator are also stocked individually for replacement work. Ordering them together as this matched package keeps the condensing unit and coil capacities aligned at freezer design conditions. Both 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
KFO400L4SDB Outdoor Condensing Unit
- 4 HP ZF13K4E low-temperature scroll compressor rated for walk-in freezer duty
- Approximately 12,990 BTUH at 95°F ambient and -20°F saturated suction on R448A or R449A
- Integral liquid sub-cooling circuit 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 defrost termination provisions for the matched electric-defrost evaporator
- 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 22.4 rated load amps and 129 locked rotor amps, on a 34.2 amp minimum circuit ampacity with 50 amp maximum overcurrent protection
KL6E105DDASC Low Profile Unit Cooler
- 12,400 BTUH with R448A or R449A at -20°F SST and 10°F TD, and 10,500 BTUH on R404A
- Two electronically commutated (EC) fan motors moving 1,550 CFM through a draw-through air pattern
- Timed electric defrost with approximately 2,250 watts of heaters (about 9.8 amps at 230V), required for low-temperature freezer service
- 6 fins-per-inch coil using enhanced copper tubes mechanically expanded into corrugated aluminum fins with die-formed collars
- Multi-circuit coil fed by a refrigerant distributor with a factory-mounted thermostatic expansion valve selected for R448A and R449A service
- Embossed aluminum casing with baffled fan sections, NSF compliant and designed to mount flush to the freezer ceiling
- Removable drain fitting at the bottom of the pan; a heated drain line is recommended in freezer service to prevent refreeze
- 208-230V EC fan motors with a separate 230V electric-defrost heater circuit, 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 freezer is the KFO400L4SDB system designed for?
It is matched to walk-in freezers up to about 12 ft × 18 ft holding a -10°F box, with a rated system capacity near 12,896 BTUH at -20°F SST. Confirm against a calculated freezer load, since a freezer carries a much higher heat load than a cooler of the same size.
How is the KFO400L4SDB different from the next size up?
The 5 HP KFO500L4SDB steps up to more capacity and a larger box; if your calculated load is near the top of this system's range, the next size is the safer choice.
What electrical service does the KFO400L4SDB require?
A dedicated 208-230V single-phase, 60 Hz circuit for the condensing unit, drawing about 22.4 rated load amps with a 34.2 amp minimum circuit ampacity and 50 amp maximum overcurrent protection. The evaporator, including its electric defrost, is a separate 208-230V connection.
Why does the KFO400L4SDB use electric defrost instead of air defrost?
Below freezing, coil frost builds faster than off-cycle air can melt it, so the matched KL6E105DDASC evaporator uses about 2,250 watts of electric defrost heaters on a timed cycle to keep the coil clear.
What evaporator comes with the KFO400L4SDB system?
The KL6E105DDASC low-profile electric-defrost unit cooler, a two-fan coil moving 1,550 CFM, factory-matched to this condensing unit's capacity at freezer conditions.
Can the KFO400L4SDB be used for a walk-in cooler instead of a freezer?
No. It is built for low-temperature freezer service with electric defrost. A medium-temperature cooler uses different equipment with air defrost and a higher box temperature.
Kramer KFO Condenser Technical SpecificationsKramer Installation GuideKramer Maintenence ManualKramer KL6 Technical SpecificationsKramer KL6 CatalogKramer Warranty
