Atosa Refrigerator and Freezer Set Temperature

Setting the temperature on an Atosa or Dukers commercial refrigerator or freezer takes about 5 seconds — press SET, use the arrows, press SET again. But if your unit isn't holding temp, or you need to change the temperature differential (OT), the low/high allowance (LS/US), or the fan control (FC), you'll need to step into the Dixell controller's secondary menu. This guide walks every adjustment with video for each one.

Every Atosa and Dukers commercial refrigerator, freezer, sandwich prep table, and pizza prep table ships with a Dixell digital controller — the small thermostat on the front of the unit. Dixell controllers are also used in blast chillers and HACCP-compliant cooking equipment, which is why the same procedures apply across the line.

Recommended setpoints for commercial refrigerators and freezers

Before you adjust anything, here's what your unit should be holding. These are FDA Food Code-aligned setpoints used in restaurant, c-store, and warehouse kitchens:

Unit type	Recommended setpoint	FDA limit
Commercial refrigerator (reach-in, undercounter, prep table)	38°F (range 35–38°F)	≤ 41°F
Commercial freezer (reach-in, undercounter)	0°F (range 0°F to -10°F)	≤ 0°F
Walk-in cooler	38°F	≤ 41°F
Walk-in / industrial freezer	-10°F (added margin for door swings)	≤ 0°F
Ice cream freezer	-10°F to -20°F	Below -5°F for scoopable

Set your refrigerator to 38°F or your freezer to 0°F using the SET button procedure below. If the cabinet won't hold temp at the setpoint, the issue is almost always a parameter in the L2 menu (OT, LS, US, or FC), a dirty condenser coil, or a worn door gasket — not the controller itself.

How to set the temperature on Atosa and Dukers refrigerators and freezers

This is the day-to-day adjustment for your visible cabinet temperature:

1. Press the SET button for 1 second. The temperature value will start blinking after a few seconds.
2. Use the UP and DOWN ARROW buttons to increase or decrease the value.
3. Press SET again to confirm the new temperature.

Manual defrost

To trigger an immediate defrost cycle, press and hold the DOWN ARROW button for more than 3 seconds.

How to change the temperature differential (OT) on a Dixell controller

The OT setting controls how many degrees the cabinet will drift below setpoint before the compressor restarts (also called hysteresis offset). If your monitor reads 39°F and OT is set to 3, the unit pulls down 3°F below the displayed setpoint before cycling. Atosa ships OT pre-configured — only adjust if your unit is short-cycling or running too cold.

1. Hold down both bottom buttons — SET (right) and AUX/Down Arrow (left) — at the same time.
2. The monitor will read nP. Keep holding until it reads HY. Release — the monitor will read LS.
3. Press the UP arrow until the monitor reads ot.
4. Press SET. The current OT value will display.
5. Use the arrow keys to set the desired differential.
6. Press SET again. The monitor will flash and return to the main frame.
7. Wait — the monitor will return to the temperature reading.

How to change the lowest temperature allowance (LS) on a Dixell controller

The LS parameter caps how cold the user can dial the cabinet. On Atosa refrigerators, factory LS is 32°F so the user can't accidentally freeze produce. On freezers it's set lower. Adjust LS only if you need to lock the unit out of certain ranges.

1. Hold down SET (right) and AUX/Down Arrow (left) until the monitor reads HY.
2. Release — the monitor will read LS.
3. Press the UP arrow until the monitor reads LS (you should already be there).
4. Press SET. The current LS value will display.
5. Use the arrow keys to choose the desired lowest allowable temperature.
6. Press SET again. The monitor will flash and return to the main frame, then back to the temperature reading.

How to change the highest temperature allowance (US) on a Dixell controller

The US parameter sets the upper limit the user can dial the cabinet to. This is the ceiling — the unit's cooling cycle begins working from this value. Atosa ships US at 41°F on refrigerators (the FDA Food Code limit), which prevents accidentally setting the unit warmer than legal.

1. Hold down SET (right) and AUX/Down Arrow (left) until the monitor reads HY.
2. Release — the monitor will read L2 (or LS depending on firmware).
3. Press the UP arrow until the monitor reads US.
4. Press SET. The current US value will display.
5. Use the arrow keys to set the desired highest allowed temperature.
6. Press SET again. The monitor will flash and return to the main frame, then back to the temperature reading.

How to change the fan control setting (FC) on a Dixell controller

The FC setting determines how the evaporator and condenser fans behave during the defrost cycle. The default CY shuts both fans off during defrost. Switching to OY keeps the evaporator fan running continuously — useful if you have airflow problems but slightly less efficient. Atosa MBF8505GR and similar 27-inch one-door 19.1 cu. ft. units use this same procedure.

1. Hold down SET (right) and AUX/Down Arrow (left) until the monitor reads HY.
2. Release — the monitor will read LS.
3. Press the UP arrow until the monitor reads FC.
4. Press SET. The monitor will display CY.
5. Press the UP arrow once. The monitor will display OY.
6. Press SET again. The monitor will flash and return to the temperature reading.

How to reset an Atosa refrigerator or freezer

If the controller display is frozen, the unit is showing an error code, or you've adjusted parameters by mistake and want to start over, use this sequence:

1. Power cycle the unit. Switch the breaker off (or unplug), wait 5 minutes, then restore power. The controller boots through T1 and T2 U — this is normal, not an error. The display switches to cabinet temperature in 15–30 seconds.
2. Verify the visible setpoint. Press SET briefly — confirm 38°F (refrigerator) or 0°F (freezer).
3. If parameters are scrambled, walk the L2 menu against factory defaults using our Dixell controller parameter guide. Atosa Dixell controllers don't have a single "factory reset" button — the parameter table is the factory default.
4. If the keypad is locked (display shows POF), hold SET + UP + DOWN simultaneously for 3 seconds. The display switches to POn (unlocked).

If the unit still won't hold temperature

If you've set the cabinet temperature, verified L2 parameters, and the unit is still running warm or cold, the problem isn't the controller. Check these in order:

• Condenser coil — pull the front grille and inspect. Dust-clogged coils are the #1 cause of warm-running Atosa units. Brush or vacuum monthly.
• Door gasket — close the door on a dollar bill. If you can pull it out without resistance, the gasket is shot.
• Evaporator coil — if iced over, the defrost cycle is failing. Verify the OT, FC, and defrost interval (id) parameters.
• Ambient temperature — Atosa units are rated to 100°F ambient. A kitchen at 110°F won't hold cabinet temp.

For broader troubleshooting, see our Atosa operating instructions.

Frequently asked questions

How do I set the temperature on an Atosa refrigerator?

Press the SET button for 1 second until the value blinks. Use the UP or DOWN arrow to change it. Press SET again to confirm. Atosa refrigerators should be set to 38°F.

What temperature should an Atosa freezer be set at?

0°F (-18°C) is the standard setpoint. Some operators run -10°F for added margin during defrost cycles. Ice cream and frozen dessert applications go colder, around -10°F to -20°F.

What temperature should a commercial refrigerator be set at?

38°F is the operational target. The FDA Food Code requires Time/Temperature Control for Safety (TCS) foods to be held at 41°F or below, so 38°F gives you a 3°F buffer for door swings during service.

What temperature should a commercial freezer be set at?

0°F or below. Walk-in and industrial freezers often run -10°F for extra margin during defrost. Ice cream freezers run -10°F to -20°F.

How do I adjust the temperature differential (OT) on an Atosa refrigerator?

Hold SET + AUX/Down Arrow until the display reads HY, release, then press the UP arrow until ot appears. Press SET, use the arrows to set the value, press SET again to lock it in.

How do I change the lowest setting (LS) on a Dixell controller?

Hold SET + AUX/Down Arrow until the display reads HY, then release to see LS. Press SET, dial in the desired lowest allowable temperature with the arrows, then press SET again.

How do I change the highest setting (US) on a Dixell controller?

Hold SET + AUX/Down Arrow until the display reads HY, release, press the UP arrow until US appears. Press SET, set the desired highest allowed temperature, press SET again.

How do I change the fan control (FC) on a Dixell controller?

Hold SET + AUX/Down Arrow until HY displays, release, press UP arrow until FC appears. Press SET — the display reads CY. Press UP once to switch to OY (evaporator fan runs continuously). Press SET to confirm.

How do I run a manual defrost on an Atosa unit?

Press and hold the DOWN ARROW button for more than 3 seconds. The unit will start an immediate defrost cycle.

How do I reset an Atosa refrigerator?

Switch the breaker off (or unplug), wait 5 minutes, restore power. The controller boots through T1 and T2 U — this is the normal startup sequence, not an error. After 15–30 seconds the display returns to cabinet temperature. A power cycle does not wipe parameters.

Why is my Atosa freezer not freezing?

Check setpoint first (press SET briefly). If the setpoint is 0°F but the cabinet runs warm, the cause is almost always a dust-clogged condenser coil, an iced-over evaporator (failed defrost cycle), a worn door gasket, or ambient temperature above 100°F. Check each in that order before calling a tech.

Where do I find the Atosa refrigerator manual?

Each Atosa unit ships with a printed Dixell controller manual referencing the L2 parameter table. If you've lost it, our Dixell controller parameter guide lists every parameter and its factory default.

Can I switch the Dixell display from Fahrenheit to Celsius?

Yes. In the L2 menu, scroll to CF and change it from 1 (Fahrenheit) to 0 (Celsius). Press SET to lock it in.

Related guides

• Atosa Dixell Controller Settings: The Complete Parameter Guide
• Atosa Refrigerator and Freezer Operating Instructions
• Commercial Refrigerators Buyer's Guide
• Commercial Freezer Guide: Types, Features, and Buying Tips
• What Is HACCP Food Safety?
• Shop Atosa Commercial Refrigerators
• Shop Atosa Commercial Freezers
• Replacement Dixell Digital Controllers