HTP Error Code F06: Return temperature high (Boiler)
HTP error code F06 on a boiler means: Return temperature high. It is also called HTP diagnostic code F06.
Homeowner? What HTP code F06 means for you
Stop and call Your boiler is reporting: Return temperature high. This code is a safety shutdown. Turn the boiler off and call a licensed technician. Do not keep resetting it. If you smell gas, leave the house and call your gas utility or 911 from outside.
Safe things you can check yourself
- Check the thermostat: right mode (Heat or Cool), set a few degrees past room temperature, and fresh batteries if it uses them.
- Make sure the unit has power: its on/off switch (often looks like a light switch near the unit) is ON and the breaker in the electrical panel is not tripped.
Call (647) 657-2977Book a service call
Licensed technicians serving Vaughan, Toronto and the GTA.
What does HTP error code F06 mean?
Return water temperature too high. At or above 210 F the message shows and clears when below 194 F. Above 230 F it becomes a lockout with FAULT light and LOCKOUT flashing. Pump on.
Applies to: EL-80, EL-110, EL-150, EL-220, EL-299, EL-399 (N/LP)
Common causes of HTP code F06
- Circulator not running or low flow
- Boiler circulator pumping the wrong way
- Return thermistor fault
HTP models that use code F06
EL-80 LPEL-80 NEL-110 LPEL-110 NEL-150 LPEL-150 NEL-220 LPEL-220 NEL-299 LPEL-299 NEL-399 LPEL-399 N
Other HTP Boiler codes
HTP code F06: homeowner questions
What does HTP code F06 mean?
Return temperature high. Return water temperature too high. At or above 210 F the message shows and clears when below 194 F. Above 230 F it becomes a lockout with FAULT light and LOCKOUT flashing. Pump on.
Is it safe to keep using my boiler with code F06?
No. Code F06 is a safety shutdown, so keep the boiler off until a licensed technician has checked it.
Can I reset HTP code F06 myself?
Do not keep resetting it. Repeated resets can hide a safety problem; a licensed technician needs to find the cause.
Who can fix HTP code F06 near me?
Aurora Star Tech Inc. repairs HTP boilers in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.
Homeowner help: Boiler Not Heating: What to Check
Troubleshooting guides
- Condensing/corrosion of conventional boiler All brands · Boiler
- No heat or some zones cold All brands · Boiler
- Noise All brands · Boiler
- Poor heat / circulation All brands · Boiler
- Relief valve weeps every cycle / pressure climbs All brands · Boiler
- Short cycling / wasted fuel All brands · Boiler
- Symptoms of air in system All brands · Boiler
- Uneven heating All brands · Boiler
- Won't fire All brands · Boiler
- Boiler overheating lockout (F00, F05, F06) HTP · Boiler
- Cascade set-up HTP · Boiler
- Check thermostat circuit for stray voltage HTP · Boiler
- False flame signal with burner off (F11) HTP · Boiler
- Fan speed error (F13) HTP · Boiler
- Flame drops out while running (F10) HTP · Boiler
- Lockout on ignition (F09, no flame) HTP · Boiler
- Menu access codes HTP · Boiler
- Pump service mode to purge air HTP · Boiler
- Read fault history HTP · Boiler
- Reset a lockout HTP · Boiler
- Reset the maintenance reminder HTP · Boiler
- Start-up combustion and gas checks HTP · Boiler
- Test mode (fixed-fire, gas pressure and combustion) HTP · Boiler
- Thermostat calling but boiler not firing HTP · Boiler
Source: Elite EL-80 N Installation Manual (LP-293), p. 70, p. 71. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.