''FLO'' or ''OH'' Reading
"FLO" or "OH" Reading On The Topside Control
This is the most common issue that can happen with your spa. A FLO/OH reading on the control panel is a result of the heater sensing a lack of water entering the chamber and it will keep your spa from heating. However, the spa pumps will still work. Almost always, it is due to dirty filters.
To verify that the filters are causing the FLO/OH message, perform the following steps:
- Turn the power off to the spa.
- Remove the filters from the spa and any loose items floating in the tub that may get sucked into the plumbing lines.
- Wait a couple of minutes, turn the power back on (with filters out) and the FLO message should go away.
- Clean filters thoroughly with Minute Rinse or Filter Fresh and reinstall.
If the message still does not go away, call Crystal Pools Spa Service at (717) 534-1837.


