- Heat pumps
- Air-to-water heat pump
E14
Viessmann E14 on a Vitocal heat pump: high pressure protection
Risk level
Medium
Proceed carefully and stop if the check is unclear.
Urgency
Medium
Quick answer
On the Viessmann Vitocal 100-AW, E14 means the high pressure protection of the outdoor unit refrigerant circuit has tripped. Review the programmed temperatures and keep air moving freely around the unit; the rest is work for an F-gas certified technician.
Safety first
Stop and check this first
- The Vitocal 100-AW outdoor unit uses R32, a flammable refrigerant: if a leak is possible, keep flames, hot surfaces and phones or other battery devices away, ventilate the area and do not touch the circuit.
- Heat pump pipes and parts can be very hot, or cause frostbite when cold; do not handle them while looking into E14, and let the technician switch off and let the unit settle before working.
Safe checks you can perform
- Check the message and note the mode
- Review the temperature setpoints
- Clear the airflow if it trips when cooling
- Watch for E34
Leave these tasks to a qualified professional
- Do not attempt this professional task: Test the high pressure switch and expansion valve
- Do not attempt this professional task: Inspect the heat exchanger and fins
- Do not attempt this professional task: Check the refrigerant charge
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.
Test the high pressure switch and expansion valve
What they doAfter three minutes at standstill, the technician uses a multimeter to see whether the high pressure switch is closed and checks its connection; then they vary the electronic expansion valve opening while watching pressures and temperatures.
They must show youthe multimeter reading and how the pressures react when the valve moves.
In writingwhether the switch, valve, coil or filter was reconnected or replaced.
Inspect the heat exchanger and fins
What they doThey look for scale at the inlet and outlet of the plate heat exchanger and for dirt or debris in the finned coil, and clean what is needed.
They must show youphotos of the heat exchanger or fin condition.
In writingwhat was cleaned and the method used.
Check the refrigerant charge
What they doAn F-gas certified technician connects the gauge, starts heating after the fault clears and works out the gap between condensing temperature and the exchange circuit temperature; if the unit is overcharged, they evacuate, pressure test and charge the nameplate amount.
They must show youthe high pressure reading and that temperature gap.
In writingthe final refrigerant quantity charged.
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.
Check the message and note the mode
When Fault appears on the controller, look up which message it is and confirm it, which is what the manual asks of the user. Write down whether the heat pump was heating, making hot water or cooling, because Viessmann ties some E14 causes to heating and others to cooling.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
Review the temperature setpoints
The troubleshooting guide lets the user check and correct settings such as the heating curve or the hot water setpoint. If someone raised those temperatures recently, return them to the usual values or temporarily lower the hot water one and watch whether E14 returns.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
Clear the airflow if it trips when cooling
If E14 appears while cooling, check from outside that no boxes, covers, plant pots or drying laundry sit in front of the outdoor unit air inlet or outlet. Remove only loose items; do not clean the fins or open panels, as that cleaning is for the professional.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
Watch for E34
If the message keeps returning and changes to E34, the outdoor unit has logged three high pressure trips and needs a manual reset. Do not cycle the power again and again: the manual states the heat pump has no user serviceable parts.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
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
- Viessmann
- Product type
- Air-to-water heat pump
Known code variants
- aerotermia Viessmann E14
- Balay dishwasher E14
- Balay E14
- Bosch dishwasher E14
- Bosch E14
- Bosch E14 error
- Bosch E14 lavavajillas
- Bosch Geschirrspüler Fehler E14
- code erreur E14 lave-vaisselle Bosch
- code erreur E14 lave-vaisselle Siemens
- codice E14 Bosch
- codice E14 Siemens
- código E14 Bosch
- código E14 Siemens
- E14
- E14 Bosch dishwasher
- E14 lavavajillas Balay
- E14 Siemens dishwasher
- E18
- E:14
- erreur E14 Bosch
- erreur E14 Siemens
- Error 14
- Error E14 Balay
- error E14 lavavajillas Bosch
- error E14 lavavajillas Siemens
- errore E14 lavastoviglie Bosch
- errore E14 lavastoviglie Siemens
- F14
- F:14
- Fehlercode E14 Bosch
- Fehlercode E14 Siemens
- LG air purifier E14 E18 UV nano check
- LG PuriCare E14
- LG PuriCare E18
- Philips cafetera E14
- Philips E14
- Philips error 14
- Philips espresso overheated
- purificador LG E14 E18 UV nano
- Siemens dishwasher E14
- Siemens E14
- Siemens Geschirrspüler Fehler E14
- Viessmann E14
- Viessmann Vitocal 100-AW E14
- Vitocal 100-AW AM2V E14
- Vitocal alta presión E14
- Vitocal E14
- Vitocal high pressure protection
What it means
In the outdoor unit fault table of the Vitocal 100-AW AM2V installation, service and operating manual (Viessmann 6221389-11, English edition for North America), E14 is listed as High pressure protection. Six causes are given: a damaged or badly connected high pressure switch, scaling in the plate heat exchanger (heating), dirty fins or poor ventilation (cooling), abnormal throttling, high outlet water temperature and an excessive refrigerant charge. If E14 trips three times, E34 appears and the outdoor unit needs a manual reset. The code by itself does not show which of those causes is at work.
Warnings and stop conditions
- Highsource verified
The Vitocal 100-AW outdoor unit uses R32, a flammable refrigerant: if a leak is possible, keep flames, hot surfaces and phones or other battery devices away, ventilate the area and do not touch the circuit.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
- Mediumsource verified
Heat pump pipes and parts can be very hot, or cause frostbite when cold; do not handle them while looking into E14, and let the technician switch off and let the unit settle before working.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
Symptoms and causes
Probable causes · in order
- Scale in the plate heat exchangerPossible
In heating mode, scale built up at the inlet, outlet or inner walls of the plate heat exchanger hinders heat transfer to the water; Viessmann asks for a professional to clean it.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
- Dirty outdoor coil when coolingPossible
In cooling mode the outdoor coil has to reject heat; if the fins are dirty or something blocks the return air path, pressure rises and the manual calls for cleaning.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
- Outlet water running too hotPossible
A setpoint close to the limit, or an outlet sensor reading several degrees below the real temperature because of poor contact, drives the unit to high pressure; the remedy is better sensor contact and insulation.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
- High pressure switch or abnormal throttlingPossible
A badly connected or failed high pressure switch gives a false signal, and an electronic expansion valve that is stuck, has a faulty coil or is dirty upstream causes abnormal throttling.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
- Refrigerant overchargeLess common
If the circuit holds more refrigerant than the nameplate states, the technician detects it with gauges and corrects it by recovering, evacuating and charging the right amount.
Evidence: Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
Virtual technician
Does E14 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
Viessmann Vitocal 100-AW AM2V installation, service and operating instructions 6221389-11
Viessmann · 2026 · manual
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