Aerothermal heating with underfloor heating is undoubtedly one of the most efficient options for heating a home, since Aerothermal underfloor heating problems: causes, prevention and solutions
Whether in apartments or single-family homes, aerothermal underfloor heating offers comfort and energy efficiency. However, if not properly designed, installed, or maintained, problems can arise that affect performance, comfort, and expected savings.
Based on our experience as installers, we’ve compiled a list of the most common problems with underfloor heating: why they occur, how to prevent them, and what to do if you’re already experiencing them.
Problems with underfloor heating by aerothermal energy
High initial investment
Installing an air-source heat pump with underfloor heating requires a significant investment, especially in new construction. This includes leveling floors, installing insulation, adapting the electrical system, and performing civil engineering work.
How is it compensated?
- Preliminary energy study to estimate medium and long-term savings.
- Access to subsidies and tax deductions.
- Average amortization of 5-7 years in well-insulated homes.
Loss of efficiency in cold climates
Air source heat pumps reduce their performance when the outside temperature drops below 5°C. The system requires more energy to maintain indoor comfort.
Solutions:
- Inverter equipment with oversized power for cold climates.
- Support systems such as electric resistance, solar thermal or hybrid boiler.
High thermal inertia
Underfloor heating takes time to warm up, as it must first raise the temperature of the concrete before heating the room.
How to manage it?
- Program the system to maintain a constant temperature.
- Combine with fast emitters (low temperature radiators or fan coils).
Condensation in cooling mode
In cooling mode, if the floor cools below the dew point, condensation may occur, posing a risk to flooring and furnishings.
Prevention:
- Install humidity probes and dew point sensors.
- Use dehumidifiers or controlled ventilation.
- Limit the minimum water temperature in summer.
Uneven heat distribution
Colder or warmer areas within the same home are often due to poor hydraulic design or uneven insulation.
Solution:
- Appropriate technical calculation of flow rates and lengths.
- Manifolds with hydraulic balancing valves.
- Homogeneous thermal insulation throughout the home.
Leaks in the installation
Although rare, leaks can be caused by installation errors or poor-quality materials.
Recommended action:
- Turn off the system and check pressure.
- Request a leak test to locate the leak.
- Repair prioritizing areas accessible from collectors.
Visual and sound impact of the outdoor unit
The outdoor heat pump can be annoying if not chosen and located correctly.
Recommendations:
- Select quiet models (40-55 dB).
- Place it in protected areas (patio, deck, shed).
- Use anti-vibration mounts and acoustic barriers if necessary.
Need for permits and work
Installation may require administrative procedures, especially in renovations and residential communities.
Advice:
- Hire an installer to manage permits and the project.
- Evaluate alternatives if there is no outdoor space.
Electrical overload
An air-source heat pump system requires adequate contracted power. In some cases, it will be necessary to increase this power.
Prevention:
- Load study before installation.
- Evaluate tariffs with time discrimination or photovoltaic self-consumption.
How to prevent problems from the start
- Conduct a professional energy study.
- Evaluate the level of insulation in the home.
- Check the compatibility of the flooring with underfloor heating.
- Confirm sufficient space for the outdoor unit.
- Have certified installers.
- Establish a preventive maintenance plan.
Common problems in already installed systems
Underfloor heating does not heat
It may be due to low pressure, air in the circuit, stopped pump, closed valves or misuse of the thermostat.
A room does not heat
Localized faults are usually linked to hydraulic imbalances, closed valves or a faulty thermostat.
Flowmeter not working
If it doesn’t spin or rotates poorly, there may be limescale, dirt, or a mechanical failure. Inspect and clean.
The system takes a long time to warm up
It could be a combination of low flow temperature, poor regulation, or high thermal inertia without compensation.
It makes noise
The noise indicates air in the circuit, expansion, or improper fastening. It’s necessary to bleed and check the pipe fastening.
Loss of pressure
If the pressure drops frequently, it could be due to a leak, a faulty bleeder, or a problem with the expansion tank.
Problems in the collector
There may be stuck valves, unbalanced flow rates, or small leaks. Periodic cleaning is essential.
Thermostat not responding
A faulty or poorly located thermostat affects comfort and efficiency. Check power supply, sensors, and location.
Humidity and condensation problems
Condensation in cold mode
This is one of the greatest risks. It occurs when the ground is colder than the dew point of the ambient air.
Prevention:
- Surface humidity and temperature sensors.
- Zone control and adequate ventilation.
Humidity due to poor insulation
If the building envelope is not well insulated, unwanted condensation can form.
Condensation on furniture and walls
Airtight or unventilated areas can cause secondary dampness. Increase ventilation and use probes in each room.
Underfloor heating maintenance to avoid failures
Periodic purging
Air in the system reduces performance. It’s essential to bleed it after installation and at least once a year.
Annual review
Check pressure, expansion tank, thermostats, pumps, and valves. Ideally before winter.
Cleaning the collector
The collector may accumulate limescale or sludge. Annual cleaning helps maintain balanced flow rates.
Reactivation after months of inactivity
Before restarting the system (for example, in the fall), it is advisable to check the purges, flow rates, and pressure.
What to do if you already have problems with your system
- Check the thermostat and programming.
- Check the circuit pressure.
- Request a technical review of the entire system (outdoor unit, collectors, pumps).
- Consider cleaning filters and checking flow meters.
- Consider upgrading your control system (thermostats, sensors).
Most problems with aerothermal underfloor heating are due to design errors, installation errors, or lack of maintenance. Having certified professionals from the start is the best way to avoid breakdowns and guarantee real, long-lasting thermal comfort.
Are you considering installing an aerothermal system with underfloor heating and want to do it right from the start? Get to know ouraerothermal installation service.
