Sundance FL1 Error Code: Low Flow or Pressure Switch

Exact scoped meaning

In the cited Sundance 680 Series owner’s manual Error Conditions section, flashing FL1 is a flow-related diagnostic message. The exact wording depends on how that spa is equipped. Do not blend the two configurations into one procedure.

Spas without the circulation-pump option (section 13.4 in that manual): a flashing FL1 means the pressure switch is not closed when jets pump 1 is activated. Proper water flow is inhibited, or the pressure switch has malfunctioned. The heater is deactivated.

Spas with the circulation-pump option (section 13.5 in that manual): a flashing FL1 means the flow switch is malfunctioning open, circulation filter cartridge 1 is excessively dirty, or an air lock has occurred at the circulation pump intake. The heater deactivates; jets pump 1 may also deactivate.

Those definitions apply only to Sundance spas and manuals that print this FL1 text. They do not apply to Jacuzzi FL1 wording, Gecko FLO, or Sundance manuals that use different messages.

Scope warning

This page covers only the cited Sundance 680 Series Error Conditions FL1 entries (models associated with that manual family on the ManualsLib listing include Burlington, Denali, Hartford, Hawthorne, Peyton, and Tacoma). Other Sundance series or newer manuals may use different panel messages. If your display does not show FL1 as that 680 Series manual describes, this article does not apply.

Confirm:

1. your spa is a Sundance 680 Series spa covered by that manual family,
2. your panel shows flashing FL1 as that manual describes, and
3. your owner’s manual matches the pressure-switch section or the flow-switch section above, not a mix of both.

Do not borrow Jacuzzi FL1 hose steps or reset language unless your Sundance manual lists them.

What the code can indicate

In the cited 680 Series manual, FL1 is a reported condition with more than one possible explanation:

• low water level
• clogged or excessively dirty filter cartridges
• trapped air (air lock)
• a pressure switch or flow switch that is not reading as the control expects

The code does not by itself prove which explanation is present. A switch malfunction is listed as a possibility alongside inhibited flow. Do not treat FL1 as a confirmed failed switch.

Related symptom guides: Why Are My Hot Tub Jets Weak?, Hot Tub Not Heating: What to Check First, and How to Tell if a Hot Tub Has an Air Lock.

Safe owner-level checks

Use only the FL1 procedure for your equipment option in the cited 680 Series manual. These checks are not guaranteed fixes.

Shared early checks in both FL1 entries:

1. Verify water level is about one inch below the lowest pillow. Add water if needed.
2. Check filters for clogging or excessive dirt. Clean or replace as Section 11.1 of that manual describes. See also How to Clean a Hot Tub Filter.

Then follow only the air-lock path that matches your configuration:

3. Without circulation pump: that manual describes loosening the upper pump head drain screw briefly to release trapped air, then retightening finger tight only. That is a pump plumbing bleed step in the equipment bay, not electrical work. Do not open the control box or touch wiring. If you are not comfortable with that documented bleed step, stop and call a technician.
4. With circulation pump: that manual describes removing filter cartridge 1 and holding a garden hose over the filter wall fitting (with a rag seal) for about 30 seconds, then reinstalling the cartridge.
5. One breaker cycle only on the circulation-pump FL1 path, and only as that entry states: if the circulation pump is not running, that section allows turning power off at the main breaker and back on to reset the circulation pump priming cycle. Do not repeat if the code returns or a breaker/GFCI trips again. The without-circulation-pump FL1 entry does not list that breaker step; do not add it there.

What not to do

Do not open the control box or any electrical enclosure. Do not touch wiring. Do not jumper or bypass a pressure switch or flow switch. Do not adjust pressure-switch screws. Do not assume Jacuzzi FL1 steps apply. Do not invent a reset sequence that your Sundance manual does not list. Do not keep cycling the breaker.

When to stop and call a technician

Contact an authorized Sundance dealer or qualified technician if:

• FL1 persists after the owner steps in your matching 680 Series entry
• a GFCI or breaker trips, will not reset, or trips again after one reset
• you smell burning, see scorching, damaged wiring, or leaks near electrical equipment
• the next step would require testing or bypassing a switch or sensor, or opening an electrical enclosure
• you need equipment access beyond ordinary filter access or the manual’s documented pump bleed step
• you cannot confirm that your model and manual match this 680 Series FL1 scope

How to confirm the code in the owner’s manual

1. Identify your Sundance model and series.
2. Open the matching owner’s manual Error Conditions / Error Messages section.
3. Find Panel Flashes FL1 and note whether your spa is listed with or without the circulation-pump option.
4. Match your panel text to that entry.
5. Follow only those numbered owner steps. If the manual says to contact the dealer when the problem persists, stop there.

Other Sundance messages TubWise has published are listed on Sundance error codes.