Diesel heater: white smoke and no start

Why does my heater blow white smoke and not start?

The Vevor CY manual uses the smoke to split a failed start in two. Manual

• Lots of white smoke: fuel is arriving. The manual sends you to the filter screen next to the ignition plug, to whether the pump sprays fuel forcefully, and to an aged ignition plug. Manual
• Little or no white smoke: fuel is not arriving. The manual lists fuel shortage, a frozen or blocked fuel circuit and a stuck pump. Manual For that case see tries to start, then E-10.

The same manual says white smoke that appears after a period of running means the atomising screen is clogged, and that over-priming causes heavy white smoke. Manual

The heater usually gives up with a flame-out or failed-start code. Which number that is depends on the controller: see the table above.

What did owners actually find?

Each line counts different owners who reported both the cause and what fixed it. Reports seen only as search excerpts are not counted, and neither is an owner who changed several things at once.

All counts are from owner reports. Owners No single cause reaches three owners, so read the table as a list of places to look, not as a ranking.

Two more owners named a cause without describing a fix: one has had E10 with flooding from a clogged ignition screen, and one gets white smoke and E10 when rain has blown into the exhaust. Owners

Notes on these cases:

• One owner clogged a new heater’s chamber with runs of 15 to 20 minutes at low heat. Owners
• One owner whose heater only smoked after months unused cured it by feeding the heater straight from the battery and cleaning dirty fuel out of the tank. Owners
• One owner’s exhaust was blocked by excess sealant and ran uphill, so it filled with fuel. Owners

What should I check, and in what order?

1. Stop. Do not keep restarting and do not prime again. Two owners flooded the burner by priming again and again. Owners
2. Check the supply during the start. The OnTrack guide says the battery should not drop below 12 V during start-up, and that the voltage across the glow plug should rise slowly to 8 to 9 V. Manual If the battery sags, fix the supply first. One owner cured a smoke-only heater by feeding it straight from the battery. Owners
3. Check the exhaust. With the heater off and cold, take the exhaust pipe off and tip it out. Fuel or water in it means it was blocking the flow. Refit it with a continuous fall so liquid drains out, as the owner with the uphill pipe did. Owners If the pipe has been extended, go back to the supplied length: one camper converter’s heater would not light with a longer exhaust and lit with the standard one. Owners
4. Look at the fuel. After long storage, drain old or dirty fuel, as one owner had to. Owners In freezing weather check that the fuel has not gelled: the Vevor CY manual lists fuel gelled by cold under flame-out. Manual
5. Service the glow plug and its screen. Two owners got a smoke-only heater running by cleaning the screen or the plug well. Owners The OnTrack guide gives 0.6 to 0.8 ohm as the reading for a good glow plug, and says that if the fuel side has been checked and there is smoke, replace the plug. Manual Steps are in cleaning the glow plug and its screen.
6. Deal with a flooded burner. The Vevor CY manual’s method is to detach the fuel line, start the heater, let it stop by itself, and repeat until there is no smoke, then reconnect. Manual One owner instead removed the unit and drained the fuel out through the air intake. Owners Do this outdoors, with a container under the open fuel line. Keep the open line and the container well away from the exhaust: the pump still delivers fuel during the dry run and the exhaust gets hot.
7. Carbon in the burn chamber. If the plug and screen are clean and the exhaust is clear, the chamber is the next suspect. Clearing it means opening the heater and fitting new gaskets.

If you are not sure, ask a technician. Opening the combustion chamber goes beyond routine owner maintenance. A mistake here can cause a fuel or exhaust leak. Stop if anything is unclear.

It started. Why is it still smoking?

The fuel left by the failed starts has to burn off. The Belief manual says to run the heater for 20 to 25 minutes to see if the smoke clears, and that smoke continuing after 25 minutes with the inlet and exhaust clear means it needs a service. Manual Dieselheat’s guide gives a similar test: if it is still smoking after 15 minutes on full power, with the air inlet and exhaust checked for partial blockage, it needs a service. Manual

One owner who had over-primed reports the heater cleared after a clean-out and two 10-minute runs on high. Owners

How do I clear the code afterwards?

Fix the cause first, then reset. What each manual says about resetting is on how to reset a locked-out heater. When you next need to fill the line, follow manual fuel priming and stop as soon as fuel reaches the heater: over-priming is what floods the burner.

When should I stop and call a technician?

• The heater still smokes after the run times above.
• The plug, screen and exhaust are all clean and it will not light.
• The chamber is damaged inside. One owner’s heater needed a new burn chamber. Owners
• The glow plug gets too little voltage although the supply at the heater is good. One owner measured that and suspected the control board, without confirming it. Owners