Vitovent 300-W Luftventilatoren Drehzahl

[AirKna113]

Hi,

Sorry for not writing in German.

I have a Vitovent 300-W with LB-1 controlling unit in operation since October 2018.

I recently noticed that at Level 3 (195 m3/h in/out) the supply air fan runs 650 RPM faster than the exaust fan.

Neddless to say, the ducting was done in a workmanlike manner, the vents  are of an appropriate shape and size, and the filters are regularly replaced.

Is this normal?

Grüße 

[Flo_Schneider]

Hello AirKna113,

the Vitovent 300-W can automatically regulate pressure differences. If there is a slight icing on the heat exchanger, the speed of the outside air fan is increased by the control. The fact that it comes to a slight icing, is normal, about the regulation also recognizes when the preheater must be turned on for outdoor air heating.

Best regards ° fl

[AirKna113]

Seat Flo_Schneider,
Thank you for your response.
I forgot to mention that when I checked the system the outside temperature was well above zero degree Celsius and that no preheater is installed. I understand that the Vitovent adapts the speeds of the two ventilators to maintain the airflow settings but, in my case, I think the difference is too high (even if no default message is displayed and the device apparently is working well).
Viele Grüße

[Flo_Schneider]

The Vitovent 300-W has a standard preheater installed. Was the difference on your ventilation unit since the commissioning so big?

Best regards ° fl

[AirKna113]

As of your question, I'm sorry, I don't remember. Considering that a possible cause can be attributed to the different type of filter used for the intake (F7) and for the expulsion of air (M5), earlier today I replaced them with two M5 filters. Nothing changed: there is a ~ 600 RPM difference, yet.
Regards.

[Flo_Schneider]

Did you check the air heat exchanger once? Maybe this is very dirty and is clogged from one side.

Best regards ° fl

[AirKna113]

Earlier today, I removed the "Gegenstrom-/Enthalpiewärmetauscher". It was clean and not damaged.

[Flo_Schneider]

If the pipes, filters and the heat exchanger are clean, there may still be a defect in the fan motor. I recommend you to contact your heating contractor.

Best regards ° fl

[AirKna113]

Thank you. I'll take your advice.
Ciao.

[prototyp]

Hello AirKna113,

Ich habe ein ähnliches Problem. Haben Sie es jemals geschafft, dieses Problem zu lösen? Ich kann keine Lösung finden – das Regenerieren/Ersetzen der Lüfter ist das Letzte, was ich noch nicht versucht habe

Hier gibt es mehr in meinem Thread:

https://community.viessmann.de/t5/Lueftung/Lauter-Betrieb-hohe-Geschwindigkeit-des-Zuluftventilators...