Hello all,

Of lately I realised i only have cold air coming from the vents, even after the engine heats up to still no hot air. I topped up the coolant and still no good. Any thoughts on what the problem is?

Cheers

What engine does your Octavia have. What quantity of coolant was necessary to bring it back up to the mark. I would have thought a warning would have been indicated if it was anything substantial.

2015, 1.6 diesel . Well it was rather low in fact and took a large quantity to bring it back up.

Diesels suffer from water pump issues but this usually is accompanied by temperature surges. Also the heater matrix can block as a result of the engine   manufacturing process and is why extra silicate in the form of a bag is put in the expansion reservoir. The fact is the system has lost coolant so look for leaks.

My heater matrix stopped providing heat recently. It was the "Mit Silikate" bag that had split in my coolant expansion tank. This had then blocked the heater matrix.

 

A side problem I discovered was that I had a lot of water in the drivers footwell. Not sure how it got there, however my coolant had also dropped prior to the issue being identified and could possibly be related if the matrix was blocked and the coolant leaked from the pipes leading to the matrix. 

 

I'd get it checked out as soon as possible, especially with the winter weather approaching. I was fortunate that I noticed the no heating in August!