I think what you suggest is quite common,
I have a T6, if you turn off the blower fan via the central knob, heat / cold air will continue to come out of the vents at the temperature previously set (before the fan was turned off)
this has been discussed previously in various threads,
simplest way to correct if for yourself: turn the fan on / select a neutral temperature, then simply turn the fan off, that way the air comming out of the vents is not detectable as either hot or cold.
I think it’s a design fault with the T6, but it’s a very common & wide spread issue.
IMO, if the dealer tries to fix it, it will be a dash out job, I now just live with it as one of the foibles of the Van.
here is one thread to get you going, use the search function (top right ) of the page
Hi, my van seems to have developed a problem with the driving heater, when the heater control is set at 22 deg, in the middle of the range at TDC, the van produces the temperature I would expect when it is warming up, however once the van is up to full temperature it starts to cool down to a...
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