Hi I have a 2015 rapid space back 1.6tdi sport 

bought in the better weather last year and once warranty run out in colder weather realised my heater system doesn’t work properly 

no fluctuation in temperature,tepid heat from vent at drivers side and cold at all others

engine up to temperature no problem fitted new auxiliary cooling pump 

checked temp flap motor is working and even flushed water through matrix to check for blockage 

I’ve now been told the matrix is blocked due to the gel bag bursting in the G30 expansion tank and it’s most likely been replaced but matrix will be clogged up although water is still able to pass through the matrix it doesn’t get through the veins 

has anyone any information on how to replace the matrix it doesn’t seem to be accessible does the dash need removed ?

I can’t find a procedure list or help videos online for this model at all 

Very common issue it seems. takes multiple flushes to get rid of the silica crap that's got into the matrix. Have a look at the octavia mk3 section, there's a lengthy thread here:

 

 

Edited 26 January, 20215 yr by DC04R
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