ᐅ Heat pumps consume a significant amount of energy and can generate considerable noise.

Hello everyone,

We have been living in our new house for one month now and are experiencing significant noise issues. The noise comes from the manifold of the underfloor heating system as well as the pump itself, which is very loud. The sounds are mostly sharp clicking or ticking noises, especially noticeable in the bedroom. The flow rate and the pump settings have been adjusted, but nothing has improved. However, it is always quiet in the early morning hours. Could it possibly be due to a setting on the unit? The heating technician has already been here but is unsure of the cause. Another technician from Bosch is scheduled to come and take a look, but I’m not sure if the pump is the problem. Also, the house is barely warming up at the current temperatures, and I am using more than 30 kWh daily, which seems very high for a 150 m² (1,615 sq ft) home.

30 kWh for 150 m² (1,615 ft²) could be sufficient given the current temperatures. However, it obviously depends on the type of heat pump (air-to-air heat pump, air-to-water heat pump, ground-source heat pump, etc.), the building standard (KfW55, 40, Passive House, etc.), as well as the number of occupants, their preferred indoor temperature, and the amount of shower and bath water used.

With the amount of information you’ve provided so far, I can only rely on my crystal ball, which is still under repair 😉

Only 80 sqm (860 sq ft) of living space is heated to 21 degrees Celsius (70°F). The rest is set to 15 degrees Celsius (59°F). The main problem preventing us from having a quiet night is the heating manifold on the upper floor. Although it is located in the hallway, it can be heard quite clearly from almost all rooms. The flow rate has already been limited, and the pump setting has been reduced from level 3 to level 1.

Interesting topic........... I’m following along here

Eldirwars schrieb:

Only 80 sq meters (860 sq ft) of living space are heated to 21 degrees Celsius (70°F). The rest is set to 15 degrees Celsius (59°F). The main issue preventing us from having a quiet night is actually the heating circuit distributor on the upper floor. Although it is located in the hallway, it can be heard quite clearly in almost all rooms. The flow rate has already been limited, and the pump setting was reduced from level 3 to level 1.

That is definitely a problem.
A heat pump especially relies on heating surface area.
If you turn off half of the heating circuits, the entire house must be heated by the remaining circuits.
This means the flow rate and supply temperature have to increase significantly to compensate for the other rooms.

You always have to keep in mind that typically houses are insulated externally, but not between rooms.

So it’s fine if you want to lower the temperature in, for example, the bedroom by 2 or 3 degrees Celsius, but reducing the temperature by 6 degrees Celsius in half of the house is a different matter.
First set the system to normal settings, see if the problem is resolved, and then please report back.

The system still needs to be properly balanced thermally, as the energy consumption is significantly too high! For comparison: a partially renovated 1970s house with a heated area of about 140 sqm (1507 sq ft), most rooms set to 21°C (70°F), the rest to 18°C (64°F), all with radiators; the gas consumption is around 80 kWh per day. With a heat pump that actually achieves a COP of 3, this would equate to about 26 kWh per day. The outdoor temperature was around -5°C (23°F). So: search for “thermal balancing” or “hydraulic balancing” online and carry it out. This process can take a full heating season but is worth the effort.

By the way: all of this assumes that the heat pump is properly sized and the electric backup heater is not running constantly. This should not be a problem in a new build.