Rotary knob diesel heater controller: LED flash codes
Updated
On a rotary controller you count LED flashes instead of reading a code, and the flash table is not the E-01 to E-10 table. On the Belief controller three flashes mean a voltage fault; on Vevor's LED-bar dial three flashes mean a glow plug fault. Find the table for your brand before acting on a count.
Is this your controller?
Also called: rotary controller, manual controller, knob controller, dial controller
A small panel with one large rotary knob and no screen or digits anywhere. The Belief and Dieselheat version has three push buttons (power control, temperature control and fan) with red and yellow LEDs beside them. Vevor's CY heaters have a related panel with a row of LEDs, a dial and separate ON and OFF keys.
How it shows a fault: No code is shown. An LED flashes a number of times, pauses, then repeats: count the flashes in one group. On the Belief and Dieselheat controller, an LED blinking evenly about once a second with no pause means the heater failed to start and has locked out. Vevor's LED-bar dial shows an unsuccessful start as 8 flashes instead.
Reported on: Belief, Dieselheat kits, Vevor CY-5001/5002/5004 (LED-bar variant).
Not a match? See the other controller families.
At a glance
| Fault display | No screen: an LED flashes a count, pauses, repeats |
|---|---|
| Codes documented | 2 flashes, 3 flashes, 4 flashes, 5 flashes, 6 flashes, 8 flashes, 9 flashes, 1 flash, 7 flashes, 10 flashes, 11 flashes, slow continuous flash, LED blinking once per second, evenly, no pauses, LED flashes 1-8 times with a pause between groups |
| Settings menu | None documented |
| Remote pairing | Not documented in our sources |
Error codes on this controller
| Code | Controller | Manual or brand | Meaning | Stated limit |
|---|---|---|---|---|
| 1 flash | Rotary knob, LEDs | Belief rotary controller Manual | Second start failure | Not stated |
| 2 flashes | Rotary knob, LEDs | Vevor CY, LED bar with rotary dial Manual | Supply voltage out of range Manual's remedy: Check whether the battery or generator is normal and whether the fuse is aged. | Normal range: 24 V controller 18-32 V; 12 V controller 9-16 V |
| 2 flashes | Rotary knob, LEDs | Belief rotary controller Manual | Heater has flamed out and tried to restart; core temperature too low Manual's remedy: Check fuel and fuel supply. | Not stated |
| 3 flashes | Rotary knob, LEDs | Vevor CY, LED bar with rotary dial Manual | Ignition plug fault Manual's remedy: Check whether the ignition plug connector is loose or the wire is shorted to the housing; inspect the plug for damage. | Not stated |
| 3 flashes | Rotary knob, LEDs | Belief rotary controller Manual | Voltage too high or too low (normally flat batteries or a poor connection to the battery) | Not stated |
| 4 flashes | Rotary knob, LEDs | Vevor CY, LED bar with rotary dial Manual | Oil (fuel) pump failure Manual's remedy: Check pump wire and connector for damage, looseness, oxidation, short and open circuit. | Not stated |
| 4 flashes | Rotary knob, LEDs | Belief rotary controller Manual | Furnace is too hot to start Manual's remedy: Wait 10 minutes and try again. | Wait 10 minutes |
| 5 flashes | Rotary knob, LEDs | Vevor CY, LED bar with rotary dial Manual | High temperature alarm Manual's remedy: Check the heating duct is clear; check the fan; check the temperature sensor. | Air inlet above 50 C; enclosure above 230 C |
| 5 flashes | Rotary knob, LEDs | Belief rotary controller Manual | Flame or hot air sensor failure Manual's remedy: Get service. | Not stated |
| 6 flashes | Rotary knob, LEDs | Vevor CY, LED bar with rotary dial Manual | Fan fault Manual's remedy: Check whether the impeller is stuck; connector loose; magnet-to-Hall-sensor clearance too large; line short/open; motor leakage. | Not stated |
| 6 flashes | Rotary knob, LEDs | Belief rotary controller Manual | Air sensor failure Manual's remedy: Get service. | Not stated |
| 7 flashes | Rotary knob, LEDs | Belief rotary controller Manual | Fuel pump not connected or fuel pump wires short-circuited Manual's remedy: Check fuel pump wiring. | Not stated |
| 8 flashes | Rotary knob, LEDs | Vevor CY, LED bar with rotary dial Manual | Unsuccessful startup Manual's remedy: 1) Casing too hot and not cooled after 3 minutes of start-up. 2) Lots of white smoke in exhaust: check the filter screen next to the ignition plug (clean/replace), whether the pump sprays fuel forcefully, whether the ignition plug is aged. 3) Little or no white smoke: check for fuel shortage, frozen or blocked fuel circuit, pump stuck/damaged, combustion intake and exhaust clear, ignition plug damaged, inner fan-wheel clearance too large. 4) Ignites normally but still reports ignition failure: check the casing temperature sensor is in full contact with the casing, its pressure spring, and the sensor itself. | Casing not cooled after 3 minutes of start-up (cause 1) |
| 8 flashes | Rotary knob, LEDs | Belief rotary controller Manual | Blower fan broken or jammed | Not stated |
| 9 flashes | Rotary knob, LEDs | Vevor CY, LED bar with rotary dial Manual | Sensor failure Manual's remedy: Check whether the temperature sensor wire/connector is damaged or loose and whether the sensor is damaged. | Not stated |
| 9 flashes | Rotary knob, LEDs | Belief rotary controller Manual | Glow plug broken or short-circuited | Not stated |
| 10 flashes | Rotary knob, LEDs | Belief rotary controller Manual | Heater has overheated during operation or the start process Manual's remedy: Check ducting, vents and heater air flow; let cool and restart. | Not stated |
| 11 flashes | Rotary knob, LEDs | Belief rotary controller Manual | Shell sensor failure Manual's remedy: Get service. | Not stated |
| LED blinking once per second, evenly, no pauses | Rotary knob, LEDs | Dieselheat fault-finding guide Manual | Rotary controller equivalent of E10: failed to start and locked out Manual's remedy: Reset by removing the fuse, then follow the no-start checks (power, fuel, air and exhaust). | Not stated |
| LED flashes 1-8 times with a pause between groups | Rotary knob, LEDs | Dieselheat fault-finding guide Manual | Rotary controller error code (the guide says 1 to 8 flashes and refers to a code list 'at the back of this guide' that is not in the 6-page PDF) Manual's remedy: Try to clear by removing the fuse near the battery, refitting it and restarting. | Not stated |
| slow continuous flash | Rotary knob, LEDs | Belief rotary controller Manual | Heater could not ignite after 2 start attempts (about 6 minutes) - locked out Manual's remedy: Remove the fuse to reset, refit and turn on again; after running out of fuel repeat up to 6 times to re-prime. | 2 start attempts over about 6 minutes |
Procedures on this controller
Clear a lock-out Manual
Remove the main fuse near the battery, refit it, and start the heater again. Dieselheat's guide says a new or run-dry heater can need up to 6 complete start cycles to pull fuel through, resetting with the fuse after each lock-out.
Run in power mode or temperature mode Manual
The power-control button starts the heater at a fixed output set by the knob; the same button turns it off. The temperature-control button makes the heater cycle to hold a temperature.
Known quirks
- Dieselheat's fault-finding guide says the rotary controller flashes 1 to 8 times and refers to a code list that is not in that PDF. The Belief table goes up to 11 flashes.
- One generic D2/D4 manual says its knob panel blinks the same numbers as the E-01 to E-10 table. The Belief table does not follow that numbering, so do not assume it for your heater.
- No priming, tuning or altitude setting is documented for this controller.
Pages that apply to this controller
- Rotary knob LED flash codes
- Reset a locked-out heater
- White smoke and no start
- Shuts down or low power
- Controller screen is blank
- Altitude tuning
- Hidden settings menu
- Soot build-up and the clean burn
- Manual fuel priming
- Pairing the remote
- Lithium, power stations and voltage errors
- Cleaning the glow plug and its screen
- All error codes in one table
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.
- Belief diesel air heater user guide, rotary control (PDF) (dieselheat.com.au)
- Dieselheat: diesel air heater fault finding guide (PDF) (dieselheat.com.au)
- Vevor diesel heater manual, CY-5001 / CY-5002 / CY-5004 (PDF copy) (xlrzbfnheqpszgtyhdkh.supabase.co)