Dear forum,
My name is Markus, and we have just moved into a condominium in Dresden [built in 2016]. My question relates to this...
The apartment has a decentralized ventilation system from the company Lunos; specifically, the e² model with heat recovery. Aside from the fact that I find the fans extremely noisy, they also don’t seem to achieve their purpose. Take our bedroom, for example: 12 square meters (129 square feet). One fan is installed. This morning, after airing out the room by opening the windows, the humidity level was 55.6%. My wife worked in this room for 3 hours. Meanwhile, the humidity increased to 64%, despite the ventilation running on the highest setting.
The system’s filter is clean, so that can’t be the problem. The fan itself works; there is airflow. But this can’t be what the system was designed for: First, the fans on the highest setting are difficult to use because they are too loud at 50 decibels. And then even this highest setting can’t maintain the current humidity level? I don’t understand. In my opinion, these fans are completely ineffective.
Since our building is very well insulated, I actually have to air out the room by opening windows three times a day, otherwise the humidity quickly approaches 70%. Three times a day! This is really annoying and should not be necessary with a decentralized ventilation system.
Am I missing something here? Is this the case with all ventilation systems?
I would greatly appreciate any input. On one hand, because I would like to find a solution [different fans?]. On the other hand, because I find the situation so unbelievable. It can’t be that these "things" have no effect...
Best regards,
Markus
My name is Markus, and we have just moved into a condominium in Dresden [built in 2016]. My question relates to this...
The apartment has a decentralized ventilation system from the company Lunos; specifically, the e² model with heat recovery. Aside from the fact that I find the fans extremely noisy, they also don’t seem to achieve their purpose. Take our bedroom, for example: 12 square meters (129 square feet). One fan is installed. This morning, after airing out the room by opening the windows, the humidity level was 55.6%. My wife worked in this room for 3 hours. Meanwhile, the humidity increased to 64%, despite the ventilation running on the highest setting.
The system’s filter is clean, so that can’t be the problem. The fan itself works; there is airflow. But this can’t be what the system was designed for: First, the fans on the highest setting are difficult to use because they are too loud at 50 decibels. And then even this highest setting can’t maintain the current humidity level? I don’t understand. In my opinion, these fans are completely ineffective.
Since our building is very well insulated, I actually have to air out the room by opening windows three times a day, otherwise the humidity quickly approaches 70%. Three times a day! This is really annoying and should not be necessary with a decentralized ventilation system.
Am I missing something here? Is this the case with all ventilation systems?
I would greatly appreciate any input. On one hand, because I would like to find a solution [different fans?]. On the other hand, because I find the situation so unbelievable. It can’t be that these "things" have no effect...
Best regards,
Markus
S
SaniererNRW1237 Oct 2022 13:53G3762mm schrieb:
Am I overlooking something here? Is this the case with all ventilation systems? No – I also have decentralized units and a consistent 55% humidity level (currently). Although I’m usually alone, I cook regularly, shower daily, and mostly work from home. I keep the units running continuously on the lowest setting. There is a humidity sensor in the bathroom, so the unit there automatically switches to the highest setting while showering.
I can’t specifically help identify the cause for you. I can only say that it shouldn’t be like that.
What are the outside temperature and humidity levels? Ventilation does not automatically dehumidify. Instead, moist warm air is expelled outside, and (through heat recovery) slightly cooler but definitely dry air (because cold air can hold less moisture) is brought in, which then absorbs more moisture inside before being ventilated out again.
However, if it is only a little colder outside but, for example, much more humid than inside (as it often is when it rains), this process doesn’t work effectively.
However, if it is only a little colder outside but, for example, much more humid than inside (as it often is when it rains), this process doesn’t work effectively.
I’ll join in here… We have now been living in the house for over five years. Currently, we consistently have indoor humidity levels above 60 percent (63–64 percent). Outside, the humidity has been over 80 percent for weeks, with plenty of rain. I checked our records… last year around this time it was similar. Later, the indoor humidity dropped again to about 55–58 percent. In 2020, we only occasionally had indoor humidity just above 60 percent. Our room temperature back then was also about 1–2 degrees Celsius (2–4 degrees Fahrenheit) higher. By the way, we don’t have any ventilation system or similar equipment.
Can I assume that the high indoor humidity is related to the outdoor conditions? Or should I be concerned that there might be a leak somewhere?
Can I assume that the high indoor humidity is related to the outdoor conditions? Or should I be concerned that there might be a leak somewhere?
W
WilderSueden24 Oct 2022 14:43That’s not unrealistic. If you have 100% relative humidity at 12 degrees Celsius (54°F), it will drop to about 60% at 20 degrees Celsius (68°F) when the air is warmed up. This is basically the air you bring in through ventilation, whether through windows or a mechanical ventilator. On top of that, there is additional moisture generated inside the house from cooking, showering, wet clothes, and so on.
Well... as already mentioned, a ventilation system is not a dehumidifier.
To reduce the humidity to around 50%, in weather conditions like we have right now (at least in my region), you need a dehumidifier or an air conditioner.
But I would say... even opening the windows doesn’t make a difference. When the outside humidity is nearly 80%, as it is here at the moment, it won’t help.
To reduce the humidity to around 50%, in weather conditions like we have right now (at least in my region), you need a dehumidifier or an air conditioner.
But I would say... even opening the windows doesn’t make a difference. When the outside humidity is nearly 80%, as it is here at the moment, it won’t help.
Similar topics