Pitco drn

What does Pitco drn mean?

On a Pitco Solstice digital controller, the display cycles drn / tUrn / oFF when the drain valve interlock (DVI) switch detects that the drain valve is open. The controller suspends all normal operation and will not heat — this is a safety interlock that prevents firing the burner with the vat draining. Heating resumes only after the drain is closed and the control is cycled.

Symptoms

• Display alternates between drn, tUrn, and oFF.
• Fryer will not heat and all normal cook functions are suspended.
• Condition appears immediately when the drain handle is moved off the closed position.
• Fault clears as soon as the drain is closed and the control is turned off then on.

Common causes

• Drain valve is physically open or not fully rotated to closed.
• Drain valve interlock (DVI) switch is misadjusted and reads open.
• DVI switch wiring is loose, broken, or disconnected.
• DVI switch has failed and reports open even when the valve is shut.

Diagnostic steps

1. 01

   Close the drain valve fully

   Rotate the drain handle completely to the closed position. A partially open valve will keep the DVI switch reporting open and the controller in the drn state.

2. 02

   Turn the control off

   Switch the controller off after closing the drain. The interlock latches the lockout, so a power cycle is required to re-evaluate the drain state.

3. 03

   Refill the vat if needed

   If oil was drained, top the vat back up to the correct fill level before restarting so the fryer heats with the vat full.

4. 04

   Turn the control on and confirm clear

   Switch the control back on. If the drain is closed and the switch is working, drn clears and the controller returns to its normal display.

5. 05

   Inspect the DVI switch if it persists

   If drn remains with the drain confirmed closed, check the DVI switch adjustment and wiring. Note that some applications do not use the drain valve input at all.

When to call a professional

Call a Pitco-authorized technician if drn persists after the drain valve is confirmed fully closed and the control has been cycled. A misadjusted or failed drain valve interlock switch, or damaged interlock wiring, needs a technician to test the switch, set it correctly, and verify the safety interlock latches and clears as designed before the fryer returns to service.