Cooling systems · Electri-Cool family

Cincinnati Sub-Zero 767: troubleshooting and error codes

The ServiceForge knowledge base holds 10 documented symptoms for the Cincinnati Sub-Zero 767, with 24 ranked causes, 8 diagnostic checks with test points and expected values, and 0 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

Unit turns on, but will not pump caution

Device powers on but water pump does not operate

Ranked causes

1. Kinks in pad/hose (common)
2. Improper connections to pad/hose (common)
3. Improper connections to PC board (occasional)
4. Defective PC board (rare)

First check

Inspect hose and pad for kinks

Test point: Entire hose and pad assembly
Expected: No kinks or obstructions visible

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Unit will not cool caution

Device operates but does not cool water to set temperature

Ranked causes

1. Air filter clogged (common)
2. Air intake blocked (common)
3. Air outlet vents restricted (occasional)
4. Defective PC board(s) (rare)

First check

Inspect air filter for clogging

Test point: Air filter element
Expected: Not 30% or more clogged with dust

4 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Ground continuity exceeds 0.2 Ohms high voltage

Ground continuity test reading above 0.2 ohm threshold

Ranked causes

1. Loose or disconnected ground (green) wire(s) (common)
2. Defective connector on ground wire (occasional)
3. Defective power cord (occasional)

First check

Measure ground continuity resistance

Test point: Ground lug to ground pin of power plug
Expected: Not exceeding 0.2 ohm, <= 0.2
Tools: Ohmmeter

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Low water warning light/audible on

Water level indicator activates even when reservoir appears full

Ranked causes

1. Reservoir water level too low (common)
2. Unit tilted (occasional)
3. Defective PC board(s) (rare)

First check

Test low water switch/indicator

Test point: Float switch in reservoir
Expected: Indicator sounds and LED lights when float is depressed

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Unit will not turn on high voltage

Device does not power up when activated

Ranked causes

1. Unit not plugged into proper voltage supply (common)
2. Blown fuse (common)
3. Loose connector (occasional)

First check

Verify power supply voltage

Test point: Power outlet
Expected: Proper voltage supply present

3 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Desired setting cannot be set

Temperature or other control settings cannot be adjusted on control panel

Ranked causes

1. Defective membrane control panel (common)
2. Defective PC board (occasional)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

LEDs will not illuminate

Display panel LEDs do not light up

Ranked causes

1. Defective membrane control panel (common)
2. Defective PC board (occasional)

2 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

Leakage current exceeds 300 microamperes high voltage

Leakage current test reading exceeds safe threshold

Ranked causes

1. Defective power supply (common)

First check

Measure leakage current in all switch and polarity combinations

Test point: Equipotential ground on back of unit
Expected: Not exceeding 300 microamperes (100/115V) or 500 microamperes (230/240V)
Tools: Leakage current tester

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Low temp warning light/audible on

Low temperature warning indicator activates

Ranked causes

1. Water used to fill pump too cold (common)

First check

Measure outlet water temperature

Test point: In-line temperature probe at outlet
Expected: Within set operating range after 5 minutes stabilization °C

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

No water flow caution

Pump operates but no water flows through hose and pad

Ranked causes

1. Defective PC board(s) (rare)

First check

Check for pump restrictions and hose blockage

Test point: Pump outlet and hose
Expected: Minimum 68 LPH (18 GPH) flow rate

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Community

0 fixes logged by technicians through their AI, with outcomes, for this model.

ServiceForge knowledge base record. Field-unverified unless technicians confirmed it. A teaching summary of the record, not a service manual. Export 2026-10-14.