Jackson Glasswasher Error Code F6: No Water in Wash Tank
F6 on a Jackson Delta HT-E-SEER glasswasher means the control could not confirm water in the wash tank, so the wash heater is locked out. Check the supply valve and pressure. If F6 returns, the fill circuit, the wash probe or the float switch needs a technician.
High: the heater is locked out and the machine will not wash until the cause is fixed.
- Code
- F6
- Maker
- Jackson
- Equipment
- Glasswashers
- Applies to
- Delta HT-E-SEER glasswasher dishmachines
What does Jackson error code F6 mean?
The wash heater should only run when the wash tank holds water. The control needs proof of that before it allows any heat, and when it cannot get it, it shows "F6 Service needed" with "No water in wash tank". The manual lists six causes: low or no water pressure, an inlet valve or fill relay that has failed, a wash heater contactor that is not turning off, a failed wash temperature input (T1) on the IO module, a failed probe T1, and a failed float switch letting heaters run with no water in the tub. On a glasswasher the tank is small, so a short supply interruption leaves the water level low very quickly. The manual's first action is to verify incoming pressure of 10 +/- 2 PSI. The later actions are service work: verifying the fill relay voltage, checking for welded contacts, using a 1.2 kOhm resistor in place of T1, and replacing the float switch.
Affected models and control systems
Jackson Delta HT-E-SEER glasswasher dishmachines. The error table is on printed pp. 25-27 of the Delta HT-E-SEER manual.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- Display reads F6 Service needed, No water in wash tank
- Cycle stops or does not start
- Little or no water visible in the tank
Possible causes
Listed in Jackson's documentation
- Low or no water pressure
- Inlet valve or fill relay failed
- Wash heater contactor not turning off
- Wash temperature input (T1) on the IO module failed
- Probe T1 failed
- Float switch failed, letting heaters run with no water in the tub
Other likely causes — what usually sits behind error code F6 on this control. A technician confirms which one it is before any part is replaced.
- A supply valve left shut after plumbing or ice machine work nearby
- A float switch jammed by detergent residue or glass chips
- A supply line with too little flow because other equipment is drawing from it
Safe checks before calling for service
- Open the machine's water supply valve fully.
- Check whether other equipment on the same line, such as an ice machine, is starving the supply.
- Turn the glasswasher off and on after a minute.
- Note whether any broken glass was in the tank and what the screen showed before F6.
How a technician diagnoses error code F6
- Confirm F6 and measure supply pressure against 10 +/- 2 PSI.
- Verify that the fill relay supplies voltage to the fill solenoid; replace the failed part.
- Check the wash heater contactor for welded contacts.
- Substitute a 1.2 kOhm resistor for T1; if the wash heater does not turn off, replace the IO module.
- Verify T1 resistance against the manual table and replace the float switch if the others pass.
- The contactor and IO module checks are made on live wiring.
- A heater run in an empty tank is damaged quickly, so water is proven first.
- Broken glass or residue around the float switch means the tank may need draining and cleaning.
How error code F6 differs from similar codes
F6 is the wash tank no-water code. F1 is its booster twin, and F3 and F8 are about the fill and door.
Technical reference
- Document
- Delta HT-E-SEER Installation, Operation, and Service Manual
- Edition
- 07610-004-54-86-E (Rev E)
- Models / control
- Delta HT-E-SEER glasswasher dishmachines
- Section
- Fault Codes / Troubleshooting, printed pp. 25-27 (PDF pp. 32-35)
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related Jackson glasswasher error codes
Is F6 an electrical code or a plumbing code?
Either. The manual lists supply pressure and fill parts alongside contactor, IO module, probe and float switch.
Can I keep washing glasses?
No. The wash heater is locked out until water is confirmed.
Could broken glass cause F6?
The manual does not say so, but a float switch that sticks with debris is covered by its float switch cause.
Need help with Jackson error code F6?
A technician confirms the cause on site and gives you the price in writing before any work starts.