Heater Problems

[Jake1]

Hi all,

Wondering if some one can help,

I’ve got 2015 GTI however doesn’t seem to be getting hot enough when the heaters are on full,

I’ve checked the Heater Core / Matrix pipes and both return and inlet are boiling hot. I’ve check the heater flap motor and it’s moving as it should & calibrated it via the controls. The car seems to get hotter when I have the fan speeds set lower / say set to 4. So the heat isn’t as hot when the blowers are on full.

Monitored via obd and coolant temperature is 212 degrees

Could it be a thermostat or heater control valve?

Thanks

[Big Col]

more likely the matrix is starting to block up - its a common problem on the platform.

[Finglonga]

Yep, as said  sounds like the Matrix, mine was the same I also needed to have the Aux  Heater pump replaced as it was not working. The matrix was clogged up and you can not flush them as they have a bypass.

[Adam T7]

A bit late unfortunately but it pays to remove the silicate bag from the expansion tank☹️