My Kolpak walk-in freezer is not getting cold — what should I check first?

Walk-in freezer warm-up almost always traces to one of five things: (1) the condensing unit on the roof / outside is not running — check the disconnect, the line-voltage at the contactor, and the high-pressure / low-pressure safety lockouts; (2) the evaporator unit cooler inside the box is iced over — force a manual defrost from the controller and inspect the defrost heaters and termination thermostat; (3) the dual-pressure or motor-protection safety has tripped on the condensing unit — reset only after identifying root cause (dirty condenser, low charge, contactor issue); (4) the controller is in a probe-fault state (P1 / P2) and has fallen back to time-only regulation; (5) door gasket leakage or door left ajar. Identify the controller make on the bezel before pulling parameters — Kolpak walk-ins ship with multiple controller platforms depending on build year and configuration.

What does P1 (or E1) mean on a Kolpak walk-in cooler controller?

P1 (newer Dixell / Carel firmware) or E1 (older revisions and Eliwell-based boxes) is a cabinet-air probe fault — the primary NTC sensor reading the box temperature is open, shorted, or out of range. The controller falls back to a timed compressor cycle (Ont / OFt parameters on Dixell, equivalent on Carel / Eliwell) so the box is no longer truly thermostatted. Box temperature drift is the symptom. Disconnect the probe, ohm it against the controller's NTC R-vs-T curve at ambient (10 kΩ at 25 °C, ~32 kΩ at 0 °C for the standard 103AT-2), and replace if open / out of range. Inspect the cable for damage from condensate, panel screws, or rodent activity. Route the new probe away from the defrost heaters and power wiring.

How do I read fault codes on a Kolpak walk-in — there is no Kolpak alarm dictionary in the manual?

Correct — there isn't one. Kolpak builds the cooler / freezer panels and door system; the electronics are OEM. Identify the controller by reading the model number on the front bezel or the inside of the controller door: a Heatcraft Beacon II module surfaces A1 / A2 / A3 / A4 / A5 / A6 alarm codes from its diagnostic menu; a Dixell XR / XW (post-2024 Copeland-branded) panel uses P1 / P2 / HA / LA / dEF / EE; a Carel ir33 / PJEZ / mPXV uses E0 / E1 / E2 probe faults plus rE / dE / Ed / EH alarm group; an Eliwell IDPlus / EWCM uses E1 / E2 probe faults and AH / AL temperature alarms. Once you have the controller part number, the OEM manual (downloadable from the Heatcraft, Copeland-Dixell, Carel, or Eliwell support portal) gives the exact alarm dictionary and parameter list.

My Kolpak walk-in is stuck in defrost — dEF or DF on the display, no cooling. What is wrong?

dEF / DF / DEF on the controller display means a defrost cycle is currently active — normal during the programmed defrost window (typically 2–6 cycles per day, 30–60 minutes each on electric defrost). The cycle should terminate when the evaporator probe Pb2 reads the end-of-defrost setpoint (dtE on Dixell, similar on Carel / Eliwell, ~+8 °C to +12 °C electric / +50 °F freezer) or when the maximum-defrost timer (MdF) expires, whichever is first. Stuck-in-defrost almost always means: (1) defrost heaters are open — isolate power and ohm out each element; (2) Pb2 sensor has fallen off the evaporator coil or failed (P2 fault may also be present); (3) MdF set too long for the heater capacity; (4) hot-gas defrost solenoid stuck closed on hot-gas systems; (5) heavy ice from chronic door / gasket leak overwhelming the defrost cycle.

What does HA (or AH) mean on a Kolpak walk-in cooler — high-temperature alarm?

HA / AH is the auto-reset high-temperature alarm — the cabinet probe has been above the AH threshold for longer than the alarm-delay parameter (Ad on Dixell). It is the everyday call-out alarm: a HACCP excursion the customer notices on a remote monitor. Diagnostic flow: (1) is the condensing unit running, or has it tripped on a safety — check pressure switches and motor protection; (2) is the condenser dirty or air-blocked — walk-in condensing units mount outside or in mechanical rooms and pull dust / leaves / lint fast; (3) is the condenser fan running and at full speed; (4) door seals and door-closer condition — a constantly-cycling door dumps heat in faster than the unit can pull it out; (5) refrigerant charge — superheat / subcooling check; (6) AH threshold set too tight to the setpoint for normal door-opening recovery. Auto-reset means the alarm clears the moment temperature returns below the threshold.

What does LA (or AL) mean on a Kolpak walk-in — low-temperature alarm in a cooler?

LA / AL is the auto-reset low-temperature alarm — cabinet probe below the AL threshold for longer than the alarm delay. On a walk-in cooler this matters because product (especially produce, dairy, beverages) freezes if box temp falls below ~+2 °C / +35 °F. Common causes: (1) the cooler thermostatic expansion valve (TXV) is hunting or stuck open, flooding the evaporator and over-cooling the box; (2) a stuck-open defrost-termination contactor or hot-gas solenoid keeping the system in extended defrost is unrelated — LA is the opposite condition; (3) defrost heater latched on (failed defrost-end signal) — cabinet over-heats then under-cools, oscillating; (4) the cabinet probe has physically dropped onto the evaporator coil and is reading suction-line temperature instead of air; (5) AL threshold set too tight to setpoint — widen the AL threshold or use a longer Ad alarm delay.

How do I identify the condensing unit on a Kolpak walk-in cooler / freezer?

Kolpak panel-built walk-ins do not include a condensing unit by default — most installs pair the panel package with a separately-shipped Heatcraft, Russell (both Heatcraft Worldwide / Lennox brands), Bohn, or Larkin condensing unit, plus a Heatcraft / Bohn / Russell unit cooler inside the box. Read the data nameplate on the condensing-unit cabinet: it lists model number, serial, refrigerant (R-448A / R-449A on newer installs replacing legacy R-404A), nominal capacity (BTU/hr at design temp), and electrical specs. The Heatcraft Beacon II controller (when fitted) reports through its diagnostic menu — A1 dirty condenser, A2 evaporator coil sensor, A3 high-pressure switch trip, A4 low-pressure switch trip, A5 oil failure, A6 phase loss. For non-Beacon condensing units, the controller is usually a Carel ir33-equivalent or Eliwell IDPlus mounted inside the box.

What are A1–A6 alarms on a Kolpak walk-in fitted with a Heatcraft Beacon II controller?

Beacon II is Heatcraft's intelligent refrigeration controller, common on Kolpak walk-ins built around Heatcraft / Bohn / Russell condensing units since the mid-2000s. The Ax alarm family: A1 dirty condenser — condenser-coil temperature too high, clean coil and check ambient airflow; A2 evaporator coil sensor failure — check probe wiring and resistance; A3 high-pressure switch trip — lockout requires reset, root-cause is dirty condenser or refrigerant overcharge; A4 low-pressure switch trip — root cause is refrigerant loss or stuck-closed solenoid; A5 oil failure on multi-compressor systems — oil-pressure differential out of spec; A6 phase loss / phase reversal on three-phase installs — verify supply and rotation. Beacon II also logs intelligent defrost (smart defrost / demand defrost) — the controller skips scheduled defrosts when there's no measurable frost, reducing energy use.

How do I reset alarms on a Kolpak walk-in controller — do they all auto-clear?

Depends on the alarm class and controller. On Dixell-based panels: probe faults (P1 / P2 / E1 / E2) auto-clear when the probe reads valid; temperature alarms (HA / LA / AH / AL) auto-clear when temperature returns within threshold; digital-input alarms (EA external alarm, CA / dA door) auto-clear when the input opens; EEPROM faults (EE) require a power cycle and may indicate controller end-of-life if persistent. On Heatcraft Beacon II: A3 high-pressure and A4 low-pressure are usually latched (manual reset via the panel safety switch and the Beacon UI); A1 / A2 auto-clear when the underlying condition resolves. On Carel ir33 / Eliwell IDPlus: AH / AL auto-reset; defrost-related alarms (dE / Ed) auto-reset; EE / E0 EEPROM and configuration faults need parameter-menu intervention. Never just "clear" an alarm without identifying root cause — latched safeties exist for a reason.

Where do I find Kolpak service literature, parts, and the controller manual?

Kolpak operator and service literature is hosted on kolpak.com and on the Welbilt service portal (welbilt.com/service). For the underlying condensing unit and controller (which carry the actual alarm dictionary), download the OEM manual directly: Heatcraft Worldwide Refrigeration (heatcraftrpd.com) for Bohn / Larkin / Russell condensing units and Beacon II controllers; Copeland (the post-2024 Emerson Climate brand owner) for Dixell XR / XW manuals at webapps.copeland.com/Dixell/; Carel (carel.com) for ir33 / PJEZ / mPXV; Eliwell (eliwell.com or invensys-controls.com) for IDPlus / EWCM. Welbilt-authorized distributors (Parts Town, Heritage Parts, TundraFMP) supply genuine Kolpak panel hardware and the OEM controller / condensing-unit parts. R-448A / R-449A / R-404A / R-22 refrigerant work requires EPA Section 608 certification.

Commercial Kitchen

Kolpak error codes, decoded.

Look up any Kolpak fault code below. Each one is grounded in Kolpak's own service documentation — the meaning, the symptoms, the causes, and the steps to clear it.

Quick answer

Kolpak (Welbilt / Ali Group) builds US walk-in coolers, freezers, and environmental rooms. Installs pair Kolpak panels with a Heatcraft or Russell condensing unit and a 3rd-party controller — Beacon II, Dixell XR / XW, Carel ir33, or Eliwell IDPlus. Codes on the display (P1 / P2 probe, HA / LA temperature, dEF defrost, A1–A6 Beacon) propagate from those subsystems.

By Nichita Herput

Co-founder & CEO · Reviewed May 2026

Working on a Kolpak unit? The complete Kolpak code pack in your inbox — free.

Kolpak sits in our Commercial Kitchen coverage. Every page here is transcribed from the manufacturer's manuals, not scraped from forums.

What error codes does Kolpak display?

Tap a code for the full breakdown — meaning, symptoms, causes, and fix steps.

Cabinet probe fault on Dixell-based Kolpak walk-ins — ohm NTC against R-vs-T curve and replace; controller drops to Ont / OFt timed cycle

Evaporator / defrost-termination probe fault — defrost ends on MdF time-out only; replace probe and verify clip position on coil

Older Dixell / Eliwell / Carel cabinet probe fault label (pre-firmware-rename) — same diagnostic flow as P1

Older Dixell / Eliwell / Carel evaporator probe fault label — same as P2; defrost time-only fallback

High-temperature alarm (auto-reset) — cabinet above AH threshold longer than Ad delay; condenser, charge, door seals, ambient

Low-temperature alarm (auto-reset) — cabinet below AL threshold; check TXV hunting, latched defrost heater, dropped probe

dEF

Defrost cycle currently active — normal during programmed window; stuck-in-defrost = open heater, failed Pb2, or MdF too long

EEPROM / parameter memory fault on Dixell or Carel — power-cycle once; if persistent, reload parameter set or replace controller

Heatcraft Beacon II high-pressure switch trip (latched) — dirty condenser, refrigerant overcharge, condenser-fan failure

Heatcraft Beacon II low-pressure switch trip (latched) — refrigerant loss, stuck-closed liquid-line solenoid, dirty filter-drier

Get the complete Kolpak error-code pack by email

Every Kolpak code, meaning and first checks in one document you can save, print or forward. Free.

Common questions about Kolpak equipment

Other Commercial Kitchen brands we cover

AskWhiz documents error codes for these manufacturers in the same vertical:

Accutemp Alto-Shaam Beverage-Air Blodgett Brema Ice Makers Bunn Cleveland Range Continental Refrigerator Convotherm Cornelius Delfield Electrolux Professional