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Diesel Heater Fix

E-05 on a diesel heater: overheating

Updated

E-05 means the heater's shell got too hot and the controller shut it down. Owners most often trace it to the hot-air side: a duct that is too long, too narrow or sharply bent, or a heater boxed in so it breathes its own warm air. First check: let it cool, then run it with the added ducting removed.

Which controller do you have?

The same number means different faults on different controllers. Match yours to a sketch first. This meaning applies to the 5-button LCD, the B2010 and the Vevor M-button panel; on the Hcalory HC-A01 knob LCD, E-05 is an inlet air sensor fault.

Not sure? Use the full controller guide

At a glance

CodeE-05
MeaningHeater shell too hot (overheat protection)
Most common causeRestricted hot-air duct: too long, too narrow, tight bend near the outlet, or a closed box
Check this firstLet it cool, then test with the long duct removed and the air inlet clear
EvidenceManuals and owner reports

What E-05 means on each controller

CodeControllerManual or brandMeaningStated limit
E-055-button LCDOnTrack Outdoor 5 kW
Manual
Over-heat
Manual's remedy: Table: check whether the temperature sensor cables are loose or faulty. Detail page (codes 5 and 6 together): check fan spins freely, nothing clogging combustion air supply or exhaust; if the unit turns itself on (fan only) check/replace the temperature sensor.
Fan-to-mainboard distance no more than 5 mm (detail page, codes 5 and 6 treated together)
E-055-button LCDD2/D4 parking heater (generic manual)
Manual
Heater overheated
Manual's remedy: Check the temperature sensor on the shell, or whether fan speed is abnormal.
Not stated
E-055-button LCDHcalory M98
Manual
Shell temperature too high
Manual's remedy: Air circulation obstructed (inlet, outlet or duct blocked); installation space too narrow; a pump with a larger fuel delivery connected incorrectly; fuel leaking from the pump one-way valve; sensor damaged.
Shell temperature exceeding 260 C
E-05Vevor M-button panelVevor XMZ-D1 / XMZ-D2
Manual
High temperature protection
Manual's remedy: Incorrect or faulty furnace temperature sensor type - replace the sensor; main board faulty - replace.
Not stated
E-5LCD, E-2 … E-10Vevor CY-5001/5002/5004, 5-key and 3-key LCD panels
Manual
High temperature alarm
Manual's remedy: Check the heating air duct is unobstructed; check the fan runs normally; check the temperature sensor.
Inlet air above 50 C; casing above 230 C
E-5LCD, E-2 … E-10Gasmate DH203
Manual
Overheating
Manual's remedy: Let the heater cool; check intake and hot-air ducts for blockage, crushing or restriction; otherwise service the fan or temperature sensor.
Inlet air above 50 C or internal heat exchanger above 230 C
E-5LCD, E-2 … E-10Liwolf all-in-one
Manual
High-temperature alarm
Manual's remedy: Check the heating airflow path is clear; fan operating correctly; temperature sensor functioning.
Inlet above 50 C; housing above 230 C
E5Rotary-switch LCD, E0 … E15Heatport H2 / H4 (EnControl)
Manual
Thermal efficiency failure
Manual's remedy: Bad fuel - replace; fuel filter blocked - clean/replace; fuel inlet blocked - clean inlet and tank; carbon in burner - replace burner; temperature sensor fault - replace the Pt1000 sensor; fuel pump fault - replace.
Not stated
E-05Knob LCD (Hcalory HC-A01)Hcalory HC-A01
Manual
Inlet air temperature sensor failure
Manual's remedy: Inlet air sensor failure - replace the main board.
Not stated
E-05B2010 (spanner button)B2010 controller
Manual
Overheating
Manual's remedy: Check whether the air inlet and outlet are blocked.
Shell temperature exceeds 260 C

Why does my heater keep overheating and showing E-05?

The heater’s shell got hotter than the controller allows, so it shut the burner down. The B2010 and Hcalory M98 manuals put the limit at a shell temperature above 260 °C (500 °F). The other manuals for these controllers give no figure. Manual

Causes, most common first:

  • A restricted hot-air duct. Five owners in four threads traced overheating to the outlet duct. Owners One heater was fine on the short 75 mm hose supplied, faulted when more 75 mm hose was added, and was fine again on 100 mm duct at 2 m or more. One overheated because of a 90-degree bend close to the heater. One shut down after about 30 minutes on level 12 with an 8 ft (about 2.4 m) hose and ran all night on level 3. The B2010 manual lists a blocked air inlet or outlet, and the Hcalory M98 manual a blocked inlet, outlet or duct. Manual
  • A heater boxed in. The Hcalory M98 manual lists an installation space that is too narrow. Manual One owner got E-05 after about 45 minutes with a toolbox lid closed; with the lid open it carried on. Owners
  • The fan. The generic D2/D4 manual says to check whether the fan speed is abnormal, and the OnTrack guide says to check that the fan spins freely. Manual One owner got E5 after a bent case made the fan rub and stall. Owners
  • Too much fuel. The Hcalory M98 manual lists a pump with a larger fuel delivery fitted by mistake, and fuel leaking past the pump’s one-way valve. Manual
  • The temperature sensor or its wiring. The OnTrack table says to check whether the temperature sensor cables are loose or faulty. The Vevor XMZ manual lists a wrong or faulty sensor and a faulty main board, and nothing else. Manual

Why does the OnTrack guide say “Over-heat” for both E-05 and E-06?

The OnTrack table prints “Over-heat” against both codes, and its detail section treats the two together. They are still two faults. The E-05 row carries the heater symbol and a temperature-sensor remedy. The E-06 row carries a fan symbol and a fan and Hall-sensor remedy, and the other manuals for the same panel call E-06 a fan or motor fault. Manual Read the number on the screen, not the wording.

How do I find what is trapping the heat?

Heatersealed burner insideCabin air inHot air outCombustion air inExhaust outinside the cabin ▲outside ▼Cabin air and combustion gases never mix in a sound heater.Intake and exhaust both stay outside; a blockage in eithermakes the burn rich and smoky.
The cabin air circuit (inlet, fan, heat exchanger, hot-air duct) is separate from the combustion air intake and the exhaust. Schematic drawing, not to scale.
  1. Let it cool down under power. The Vevor XMZ manual says not to cut the power after over-temperature protection: let the heater cool and switch off by itself, then restart. Manual If it runs normally afterwards and you know what blocked it, you are done. If E-05 returns, go to step 2.
  2. Run it with the added ducting removed. Use only the short duct that came with the heater, or none. Owners If it now runs without E-05, the duct is the cause: go to step 3. If not, go to step 4.
  3. Fix the duct. Owners solved it with a shorter run, a larger diameter, a smoother-walled duct, and by moving tight bends away from the heater outlet. Owners Look through the duct too: one owner claims, without a confirmed case, that some heaters ship with paperwork inside it. A lower power level is a stopgap with a long duct.
  4. Clear the cabin air inlet and give the heater room. Nothing should cover the inlet, and the heater should not be drawing in its own hot air inside a closed box. Manual Owners Still E-05: go to step 5.
  5. Check the fan. With the power off and the heater cold, see that the fan turns freely and nothing rubs. Manual The OnTrack detail section also says to check that nothing is clogging the combustion air supply or the exhaust. Manual Fan stiff or rubbing: see E-06.
  6. Check the sensor’s plug, and only the plug. See that the temperature sensor’s connector is seated and its wires are not damaged. Manual Do not move, bend or disconnect the sensor to keep the heater running.
  7. Think about what changed. If E-05 began after a pump was replaced, the Hcalory manual’s “wrong pump” cause applies. Manual

Changing fan speed in the settings

One owner cured E05 on the lowest setting by raising the fan speed for low power in the tuning menu. It is a single report. If you try it, write down the original pump and fan values first. A wrong mixture burns dirty and makes soot and smoke.

The tuning menu is described on the hidden settings menu.

How do I clear E-05?

Let the heater finish cooling, remove the cause and start again. The manuals give no other reset step. If it stays locked, see how to reset a locked-out heater.

When should I stop?

Stop if E-05 returns with the short duct, a clear inlet, a free fan and a seated sensor plug. What is left is the temperature sensor, the main board or the fuel dosing pump, and the Vevor manual’s remedy for the first two is replacement.

If you are not sure, ask a technician. Replacing the temperature sensor or the control board goes beyond routine owner maintenance. A mistake here can cause a fuel or exhaust leak. Stop if anything is unclear.

Is E-05 the same on other controllers?

No. Panels that show E-5 with no leading zero use it for a high temperature alarm too, with their own limits (inlet air above 50 °C or casing above 230 °C in the Vevor CY manual). On the Hcalory HC-A01 knob LCD, E-05 is an inlet air temperature sensor failure. Manual Check which controller you have.

Related questions

Why do I get E-05 after adding a longer duct hose?
Five owners in four threads traced overheating to the outlet duct: extra length in the narrow size, a rough aftermarket hose, or a tight bend close to the heater. One of them watched the chamber temperature climb in the app whenever the hose was attached. Test with the long duct removed.
Why does my heater overheat on the lowest setting?
One owner had E05 on the lowest setting after about half an hour and fixed it by raising the fan speed for low power in the tuning settings. That is a single report. Changing fan speed changes the fuel-air mixture, so write down the original values first.
Can I just disconnect the overheat sensor?
No. Never bypass or disconnect the overheat sensor or run the heater without it. It is the heater's overheat protection. Find what is trapping the heat instead.
At what temperature does E-05 trip?
The B2010 and Hcalory M98 manuals both state a shell temperature above 260 °C (500 °F). The OnTrack guide, the generic D2/D4 manual and the Vevor XMZ manual give no figure.

Where to go next

Sources

Everything on this page is compiled from the documents and discussions below. We summarise them in our own words; follow the links for the originals.

  1. OnTrack Outdoor: diesel heater troubleshooting guide (PDF) (cdn.shopify.com)
  2. OnTrack Outdoor: LCD controller instructions V1 (PDF) (cdn.shopify.com)
  3. D2/D4 parking heater 12 V/24 V user manual, Alza import (PDF) (dwn.alza.cz)
  4. B2010 controller operating manual V1.2 (PDF) (cdn.shopify.com)
  5. Vevor diesel heater manual, XMZ-D1 / XMZ-D2 (PDF copy) (tuitam.pl)
  6. Hcalory air heater user manual, M98 (PDF) (cdn.shopify.com)
  7. Hcalory HC-A01 toolbox heater user manual (archived transcription) (web.archive.org)
  8. Vevor diesel heater manual, CY-5001 / CY-5002 / CY-5004 (PDF copy) (xlrzbfnheqpszgtyhdkh.supabase.co)
  9. Owner report: chamber temperature climbs with an aftermarket duct hose attached (Reddit r/dieselheater) (reddit.com)
  10. Owner report: 8 ft hose shut the heater down on high, fine on a low level (Reddit r/dieselheater) (reddit.com)
  11. Owner report: overheat code from a sharp bend in the hot-air duct (Reddit r/dieselheater) (reddit.com)
  12. Owner report: overheating faults after extending 75 mm duct, fine on 100 mm (wildcamping.co.uk forum) (wildcamping.co.uk)
  13. Owner report: overheating from a 90-degree bend close to the heater (wildcamping.co.uk forum) (wildcamping.co.uk)
  14. Owner claim: paperwork left inside the duct tube blocks the flow (Reddit r/dieselheater) (reddit.com)
  15. Owner report: E-05 in a closed toolbox after about 45 minutes (Expedition Portal forum) (forum.expeditionportal.com)
  16. Owner report: E05 on the lowest setting fixed by raising the low fan speed (Reddit r/vandwellers) (reddit.com)
  17. Owner report: E5 after a bent case made the fan rub and stall (Reddit r/dieselheater) (reddit.com)