RL 50

RL-50

The RL-50 is a decentralized home venting system with heat recovery. Its an older version of the product found here: product website

I'm starting this reverse engineering page because it is broken now the second time which what seems to be the same problem. The air vent has blinds which open and close automatically when the system turns on or off. Currently its in a state where the blinds are always open, even when the system is turned off. See picture 1. I want to reverse engineer the PCBs and get a complete overview of the system. Maybe this way someone can have a look at the schematics and help me figure out why it keeps breaking.

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  Picture 1: Ventilation system without cover blinds open

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  Picture 2: Ventilation system without cover blinds closed

Problem description

The blinds, which you can see in picture 1 as the horizontal white elements in front of the fan, are not closing anymore if the system is turned off. Its not a big problem and the basic function of pushing the air out or pulling it in, is not affected, but the brown/red heating element gets very hot after some time and I'm worried that this could lead to a fire if i leave it like this.

This brown element on the top right of picture 1 is a heating element, which pushes out a small plastic rod if a voltage is applied on the terminal on the top left of the element, and thereby opening the blinds. It seems that there is always a voltage applied to the element. The light bulb on the bottom right of the picture 1 is lit up and probably indicating that there is a voltage applied to the heating element.