Control panel displays Er1 and grill will not start ignition cycle

Safety first: Unplug the grill from power and allow it to cool completely before opening any panels.

• Step 1 – Power reset: Unplug the Monument pellet grill for 5 minutes, then plug back in and see if Er1 clears. If it returns, continue.
• Step 2 – Inspect RTD probe inside cook chamber: Locate the small metal temperature probe (RTD) mounted on the inner left or rear wall of the cook box. Check for physical damage, heavy grease buildup, or if it has been struck by grates or tools. Clean gently with a soft cloth and degreaser.
• Step 3 – Check RTD wiring harness: Trace the RTD cable from the probe through the rear of the cook box to the control panel area. Look for melted insulation, cuts, or pinched sections where it passes through the body. Repair minor insulation damage with high‑temp electrical tape; replace the probe if wires are broken.
• Step 4 – Verify RTD connection at controller: Remove the controller mounting screws and gently pull the control panel forward. Locate the RTD connector on the main control board (usually a 2‑wire plug). Ensure it is fully seated and not corroded. Unplug and re‑plug the connector several times to clean contacts.
• Step 5 – Test continuity (advanced): With the grill unplugged, use a multimeter to measure resistance across the RTD leads. A typical RTD for Monument pellet grills will show a few hundred to a few thousand ohms at room temperature. An open (infinite) reading indicates a failed probe.
• Step 6 – Replace RTD probe if faulty: If the probe is open or physically damaged, remove the mounting screw(s) inside the cook box, pull the wire through the wall grommet, disconnect from the controller, and install a new OEM Monument RTD temperature probe in reverse order.
• When to call a technician: If the wiring and probe test good but Er1 persists, the main control board may have an internal fault and should be diagnosed or replaced by a qualified technician.