- Heat pumps
- Air-to-water heat pump
F1100
Saunier Duval F.1100 on a Genia Air Max heat pump: backup heater limiter open
Risk level
Medium
Proceed carefully and stop if the check is unclear.
Urgency
Medium
Quick answer
On the Genia Air Max with GeniaSet tower, F.1100 means the safety limiter of the electric backup heater has tripped. Check the water pressure on the display and that the valves are open; a competent person checks the limiter.
Safety first
Stop and check this first
- The Genia Air outdoor unit contains flammable R290 refrigerant. Saunier Duval requires open flames, surfaces above 370 °C and other ignition sources to be kept out of the protective area. Do not open the tower or the outdoor unit: call a competent person.
Safe checks you can perform
- Filling pressure on the display
- Stopcocks open
- Circulation, strainers and limiter
Leave these tasks to a qualified professional
- Do not attempt this professional task: Fix the flow before replacing the limiter
- Do not attempt this professional task: Test with the heater running
What a technician must be able to justify
Technician visit
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
Fix the flow before replacing the limiter
What they doThe competent person checks pump, strainers and purging, and only then resets or replaces the heater limiter.
They must show youthe circuit pressure, the clean strainer and the pump circulating.
In writingwhat caused the cut, whether the limiter was reset or replaced and its part number.
Test with the heater running
What they doAfter the repair, the competent person runs the backup heater with the circuit full and watches the flow temperature.
They must show youthe flow temperature during the test with no code.
In writingthe date and result of the test.
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Follow these steps
Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
Filling pressure on the display
- Who:
- you.
- How:
- read the filling pressure on the tower display, as Saunier Duval describes in the periodic pressure check.
- Result that matters:
- the manufacturer's minimum operating pressure is 0.7 bar.
- If it is below:
- water is missing and low flow is likely; tell the competent person so they refill and find the loss.
- If it is correct:
- lack of water is ruled out; flow, air or the limiter remain.
- Evidence to keep:
- a photo of the pressure with date and time.
Evidence: Saunier Duval GeniaSet FW 200-6 y FEW 200-6, instrucciones de funcionamiento, instalación y mantenimiento 0020291590_01
Stopcocks open
- Who:
- you, without opening the unit.
- How:
- check that the visible stopcocks on the heating circuit are open and that you did not close every radiator or underfloor loop.
- Result that matters:
- that water can circulate; Saunier Duval asks to open the stopcocks if needed.
- If a valve was closed:
- open it and still tell the competent person, because the limiter may have stayed open.
- If everything was open:
- a closed valve is ruled out; leave the diagnosis to the competent person.
- Evidence to keep:
- a note of which valve was closed.
Evidence: Saunier Duval GeniaSet FW 200-6 y FEW 200-6, instrucciones de funcionamiento, instalación y mantenimiento 0020291590_01
Circulation, strainers and limiter
- Who:
- a competent person.
- How:
- they check the building circuit pump circulation, the dirt strainers and the condition of the heater safety temperature limiter.
- Result that matters:
- whether flow is correct and whether the limiter only tripped or has a blown fuse.
- If flow was low or there was air:
- the cause is confirmed; it must be fixed before resetting or replacing the limiter.
- If flow is correct and the limiter is blown:
- overtemperature is the suspect; find where the heat came from.
- Evidence to keep:
- a job sheet with the flow reading and the strainer and limiter condition.
The backup heater runs on mains voltage. Before opening, isolate all poles and wait at least 3 minutes for the capacitors to discharge. Competent person only.
Evidence: Saunier Duval GeniaSet FW 200-6 y FEW 200-6, instrucciones de funcionamiento, instalación y mantenimiento 0020291590_01
Still not solved
If the error persists, stop here. See what the technician must do and show you.
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- Heat pumps
- Brand
- Saunier Duval
- Product type
- Air-to-water heat pump
Known code variants
- Genia Air F.1100
- Genia Air Max F1100
- Saunier Duval F1100
What it means
Saunier Duval defines F.1100 as the immersion heater safety temperature limiter open. It links it to flow too low or air in the circuit, the heater running with the circuit not filled, flow temperatures above 98 °C, which blow the limiter fuse so it has to be replaced, or heat entering from another source. The code points at the safety cut, not at a faulty heater.
Warnings and stop conditions
- Highsource verified
The Genia Air outdoor unit contains flammable R290 refrigerant. Saunier Duval requires open flames, surfaces above 370 °C and other ignition sources to be kept out of the protective area. Do not open the tower or the outdoor unit: call a competent person.
Evidence: Saunier Duval Genia Air HA 4-6 a HA 15-6 O B3, instrucciones de la unidad exterior 0020297943_00
Symptoms and causes
Probable causes · in order
- Low flow or air in the circuitCommon
The heater warms water that is not moving and the limiter cuts out. It often comes with closed valves, dirty strainers or air in radiators.
Evidence: Saunier Duval GeniaSet FW 200-6 y FEW 200-6, instrucciones de funcionamiento, instalación y mantenimiento 0020291590_01
- Circuit empty while the heater ranPossible
If the heater switched on with the circuit not refilled, the limiter trips. It fits after commissioning or a recent drain down.
Evidence: Saunier Duval GeniaSet FW 200-6 y FEW 200-6, instrucciones de funcionamiento, instalación y mantenimiento 0020291590_01
- Overtemperature above 98 °CPossible
With flow above 98 °C the limiter fuse blows and the limiter has to be replaced; a reset is not enough.
Evidence: Saunier Duval GeniaSet FW 200-6 y FEW 200-6, instrucciones de funcionamiento, instalación y mantenimiento 0020291590_01
- Heat from another sourceLess common
A boiler or another generator feeding heat into the same circuit can push up the flow temperature. Suspect it if the code matches that input.
Evidence: Saunier Duval GeniaSet FW 200-6 y FEW 200-6, instrucciones de funcionamiento, instalación y mantenimiento 0020291590_01
Virtual technician
Does F1100 still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
- 1
Was this entry useful?