Display shows EC or ECON; spa heats less frequently and may not reach set temperature quickly.

Safety: No internal electrical work is needed.

• Step 1 – Check mode setting: Press the Mode or Temp button (depending on panel) to cycle through modes until you see ST (Standard) or similar. Refer to your Tuff Spas manual for exact button sequence.
• Step 2 – Verify filtration cycles: Ensure filtration/heating cycles are set appropriately so the spa has enough run time to reach temperature.

EC is not a fault; it is a mode. If the spa still does not heat in Standard mode, investigate heater or sensor issues.