Pellet Stove Common Problems and How to Repair Them

This pellet stove troubleshooting guide covers basic problems with pellet stove operation and how to solve them. An explanation of pellet stove error codes is included.

Why Does My Pellet Stove Keep Shutting Off

The main causes of a pellet stove shutting off are wiring issues, it is not getting enough air and not enough pellets are being fed to the fire.

Does your pellet stove turn off automatically when you don’t want it to?

Let’s address all possible issues.

Wiring Issues

It’s more typical that a loose or damaged wire would make the stove stop working entirely. But it could be intermittent.

Look for wire issues on the blower(s), igniter, auger motor and the sensors like the low limit and high limit thermodiscs. Tighten or replace wires as needed.

If the circuit is tripping, one of the wires could be pinched or have a bare spot, so that contact is causing a short.

A Bad Combustion Blower

Check if the combustion blower is coming on and staying on. If it isn’t, it could be bad. A fire that isn’t fed fresh air will go off, causing the stove to turn off automatically.

Airflow Problems

There are a few potential problems with airflow.

Damper: If the combustion air damper is too far closed, it will starve the flame of oxygen, and the fire will either smoke and smolder or go out. Either way, the pellet stove might turn off automatically.

Adjust the damper to a more open position, usually about half-way open to see if that improves the stove’s performance.

Ash and dirt: Is the burn pot full? Are the holes in it caked over with ash and unburned pellets? These issues prevent combustion air from getting to the fire.  It needs a good cleaning, so air can flow freely.

Not enough fuel: This is an obvious cause for a pellet stove to turn off automatically. The  feed rate might be too low. Make sure the auger is working properly and feeding pellets to the burn pot at a rate sufficient to keep the fire from going out and shutting off the stove automatically.

Why Is Smoke Coming Out of My Pellet Stove

If you see excess smoke or a smell like smoke is coming from the unit, it could be one of these issues:

The vent pipe is blocked. This will cause exhaust smoke to back up into your home. Check the pipe for dirt or blockages like a bird or rodent nest, and clean it as needed. It’s good maintenance to clean out the pipe several times during the heating season.

The burn pot is dirty. When the stove is off, remove the burn pot. Does it smell like smoke? Give it a thorough cleaning.

Poor fuel. Cheap pellets smoke more than high-quality pellets. Also, if the pellets are damp, they will smoke and smolder rather than burning cleanly.

A seal or gasket could be damaged or loose. If visible smoke or a smell like smoke is coming from the exterior of the pellet stove, the vent pipe could be loose. Or a seal around the door or ash pan could be broken and need replacing.

Carefully inspect the unit. Tighten the vent flue connection, if needed. If the unit is emitting smoke through a bad seal, you should replace it or have it professionally repaired.

Airflow might be low. Your damper might be blocked or not open far enough. Poor air supply will cause smoldering and smoke rather than a clean-burning flame.

Remove any blockage, open your damper to the position indicated in the owner’s manual, and clean the interior of the stove regularly.

Why Is My Pellet Stove So Loud

Pellet stove noises indicating a potential problem include whistling and a grinding noise. What are the causes?

Grinding noise usually comes from the auger. The easy-to-fix issue is that the auger needs to be cleaned. Debris can hinder proper performance and causes a grinding noise.

The more expensive issue is that the auger motor is failing and needs to be replaced.

Pellet stove whistling or high pitched noises have a couple of common causes that are easy to fix.

The most typical is restricted airflow into the unit. Open the combustion damper wider to see if the whistling stops. It might also need cleaning because a buildup of ash and soot will restrict airflow too.

If that doesn’t solve the whistling noise, clean out the fines box, slide plate and any other area that air might be passing through and causing a high-pitched whistle or squeal.

Check all seams, and reseal them with silicone or other caulk recommended by your local pellet stove dealer. Open seams will allow airflow through them, and yes, they’ll whistle.

Finally, replace cracked or bad gaskets as part of regular maintenance.

Why Is My Pellet Stove Not Igniting

Igniter issues: You can check it with a voltmeter or multimeter. It should be getting 110 to 120 volts.

Is it glowing red hot? Then it’s working, but it might not be positioned properly to light the pellets. Adjust it as needed.

Not enough air for combustion is another issue. Make sure the damper is open and that the opening is clean. The fire pot must also be clean to allow for combustion air for ignition. Clear any plugged holes in the pot.

The combustion blower isn’t working. Listen for it to turn on. If it doesn’t, the stove won’t ignite, and the blower should be checked for bad wiring. It might require replacement.

Fuel isn’t being fed to the fire. Clear any blockages that are preventing pellets from getting to the fire. If the auger isn’t working, check for loose wiring or call a pellet stove technician for repairs.

What Does E1, E2, E3, E4, E5 Mean On a Pellet Stove

Here is a list of what these error codes mean.

E1 or E-1: Vacuum loss. This occurs when the flow of the exhaust isn’t sufficient, and the flue blockage switch is opening. Make sure the blower is running and that there are no blockages in the system.

E2 or E-2: Failure to start. The igniter might be bad, plugged with ash or mis-positioned. It could be a poor airflow issue too, so check and clean the intake as needed.

E3 or E-3: Over temperature limit. The stove might be dirty or the airflow plugged, so the stove is overheating. Other causes are a blower that isn’t running at proper speed and the wrong fuel type in the stove burning too hot.

E4 or E-4: Time & temperature fault. Not all models have this code. It shows that the internal temperature of the stove has dropped in a short time, possibly caused by a gap in feeding due to auger issues or by wet pellets.

E5 or E-5: Auger isn’t working. This usually means the auger fuse has blown or the auger is bad and needs to be replaced. This is another code not found on all pellet stoves.

Does the code look like 5U? It’s probably SU and indicates start up or startup. It is not an error code.

Not all manufacturers have the same error codes. So, to be sure you know what your pellet stove e-code means, consult your owner’s manual or call the dealer.

Note: They are often referred to as e codes or e-codes or flash codes.

Written by

Rene has worked 10 years in the HVAC field and now is the Senior Comfort Specialist for PICKHVAC. He holds an HVAC associate degree and EPA & R-410A Certifications. Protection Status