Dump the heater bypass valve?

[Mart8V]

Matrix has gone (misty/ grimy windows, no heat, header tank low, damp pass carpet!) and just ordered new one from VW Heritage.

Can I get rid of the bypass or am I better keeping it? Happy to order new hoses and do the lot at the same time if needed.  Car was blowing warm a week ago so I am assuming that the bypass valve is still working.  Any way to test?

New part is listed for mk3 as well so guessing it will be up for increased pressure?

[dubber36]

I got rid of mine when I changed the matrix, just to tidy things up if nothing else. The heater will burn my face off now.

[Mart8V]

Thanks for that. Will source some new hoses to tidy the engine bay. Any ideas on part numbers?!

[Waspy]

I need to do this too, cold mornings are getting a little hairy...

[dragonfly]

Some suggest using a mk3 matrix along with the straight pipes.  The bypass was a dealer fit/recall so isn't listed as a part. You could replace the bypass with copper pipes then see if the temperature changes that way you know it's the bypass.  I'm sure Heritage list the straight rubber pipes.

[gazareth]

the bypass was a safety feature fitted to prevent the heater matrix bursting and scalding your feet badly! would leave it where it is tbh.

[Waspy]

the bypass was a safety feature fitted to prevent the heater matrix bursting and scalding your feet badly! would leave it where it is tbh.

So it's either freezing toes or scalded ones? FFS.

[gazareth]

oh the irony

[Wayne]

I believe the mk3 matrix is a better / strong design so the bypass valve is not needed.

[dubber36]

I believe the mk3 matrix is a better / strong design so the bypass valve is not needed.

Quite right. The original matrix wasn't up to the job, so rather than VW changing however many millions of them under recall, they fitted the bypass valve instead. It's all down to economics.