Hatco LO h20
Low water probe does not detect water
Source: Hatco/HT-FDWD-SERIES_iom.pdf
What does Hatco LO h20 mean?
On a Hatco FDWD-series humidified holding cabinet, 'LO h20' flashes on the digital display when the low-water probe does not detect water in the reservoir. Without water, the unit cannot produce the humidity that keeps held food moist. The manual's first remedy is to refill the water reservoir following the operation-section instructions; if the message persists with the reservoir full, mineral or hardware faults are the cause.
Symptoms
- 'LO h20' flashing on the digital display
- Unit is heating but is not producing humidity inside the cabinet
- Held food drying out due to lack of moisture
- Message persists even when the reservoir appears full
Common causes
- Water reservoir is empty or low and needs refilling
- Distilled water in use, so no minerals are sensed by the low-water probe
- Probes have lime buildup
- Low water protection system is malfunctioning
Diagnostic steps
- 01
Refill the water reservoir
Refill the reservoir following the instructions in the OPERATION section of the manual; this is the manual's primary remedy for LO h20.
- 02
Add salt if using distilled water
If distilled water is used the probe senses no minerals; the manual says to add one teaspoon of salt to the water reservoir.
- 03
Remove lime from the probes
If the probes have lime buildup, follow the 'Removing Lime and Mineral Deposits' procedure in the MAINTENANCE section to remove lime.
- 04
Call service if it persists
If the message remains with the reservoir full and probes clean, the low water protection system may be malfunctioning; contact an authorized Hatco service agent or Hatco for assistance.
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When to call a professional
Handle the basics yourself first: refill the reservoir, add a teaspoon of salt if you use distilled water, and delime the probes per the manual. Call an authorized Hatco service agent or Hatco if 'LO h20' keeps flashing after those steps, because the manual attributes a persistent fault to a malfunctioning low water protection system, which requires qualified service inside an electrically live, heated unit to avoid shock or burn.
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