It's very cold out there and still being set highest, my car barely blow any hot air. Similar car of my friend can make toasty warm in the setting of 23. I had pollen filter replaced lasst year July 11k miles ago. and same time I gave a good clean of the air filter as it was fairly new. Any tips and tricks to get the hot air blowing .

 

thanks guys.

 

 

Do you have air flow at all?

 

If you have air flow but only cold, most likely the problem is heater matrix, blocked by corrosion or splitted silica bag in the coolant expansion tank. Or possibly some flap in the venting system is bad and no air is directed to the heater matrix. A scan wud help. How does your coolant look in the expansion bottle. Does your coolant tank have text 'mit silikat'?

 

If no flow, the problem is blower motor.

37 minutes ago, RattleWagon said:

1. Does your coolant tank have text 'mit silikat'?
2. If no flow, the problem is blower motor.

1) If so, then it's likely this has split and is the base cause of the heater issues.

2) In which context, can you hear the ventilation fan running when the car is idling?

Bizarrely a few weeks ago my car would only blow hot air out of the passenger side air vents with the drivers side luke warm at best. This was when it was -6 some mornings so very noticeable.

 

Booked it in and of course the bloody thing has fixed itself 😝

If driver side is right side of the vehicle that description is very often related to heater matrix problems. Often you first lose heat from right side and then all over.

 

However, self fixing points to possible problems with the control flaps. Or then the whatever blockage from the heater matrix is back in the coolant circulation, possibly finding new place to cause issues. Lets hope for the best!

I have the same issue. I was about to order a new heater matrix but I've read several posts where that was replaced and it didn't fix the issue, it turned out to be the heater control valve had failed. I have one arriving in the next few days so I'll update once I've replaced it. 

Mine struggles to blow air into the footwells. I did the flap reset operation and it improved, but just a bit.

I can't remember the exact method but there are a good few posts on Briskoda that detail what to do.

We really need a scan done via VCDS or ODBEleven.  This will show either weak or failing flap motors (a known weak point).  You should also check the cabin air filter to make sure it isn't blocked or dirty.

On 15/01/2025 at 09:09, varaderoguy said:

We really need a scan done via VCDS or ODBEleven.  This will show either weak or failing flap motors (a known weak point).  You should also check the cabin air filter to make sure it isn't blocked or dirty.

 

car is blowing air properly. it is just less hot. cabin filter is fairly clean and i gave it another clean. OBDEleven doesn't pull up any error code.

On 14/01/2025 at 10:29, Paws4Thot said:

If so, then it's likely this has split and is the base cause of the heater issues.

Can you confirm whether you have checked to see if you have the Mit Silcon and check to make sure (if you can) that the silicon bag has been (carefully) removed.  This issue is a ticking timebomb for a lot of Octavia owners.  If you are able to remove the silicon bag and it looks (even slightly) as though it has split, you will need to organise a complete flush of the cooling system.  If Silicon gets into the heater matrix, it can block it up (and hence less hot airflow)

 

I've checked. I don't have Mit Silikat. I think this is only for diesel car. Mine is petrol.

and also just to show you how clean the Pollen filter is ..

Ain't a new one of them white ???

 

It looks kind of dirty but it could be computer screen colour making it look dirty ???

 

 

3 minutes ago, Tilt said:

Ain't a new one of them white ???

 

It looks kind of dirty but it could be computer screen colour making it look dirty ???

This is Gray colour. Not dirty. i used white one before but i found the original gray colour again, so i just bought it.

 

3 minutes ago, Tilt said:

 

 

 

15 hours ago, automass said:

I've checked. I don't have Mit Silikat. I think this is only for diesel car.

Not true, mit silikat was originally fitted on ALL engine versions.

18 hours ago, Tilt said:

Ain't a new one of them white ???

 

It looks kind of dirty but it could be computer screen colour making it look dirty ???

 

 

The charcoal filter version type do look pretty dark when new. For the price of a new, OEM cabin filter, I cannot see any worth in cleaning an old one.  

PetrolDave, I’m sure I don’t have Mit Silicat in my coolant. It doesn’t say anywhere on the tank. If I had it, it should have been printed, like it is on my friend's diesel car 66plate.

18 minutes ago, automass said:

It doesn’t say anywhere on the tank.

No but the G13 stamp implies there should be a bag in there. G13 wasn't recommended for use without the bag. Some of the tanks are twin-walled with the bag out of sight in between.

Well, G13 means silicates are included in the coolant mixture itself, where as Mit Silicat- they are provided via a silicate bag if I am right. So, in my case, I shouldn't have Mit Silicat in my expansion tank. I never had coolant flushed. Just wondering if coolant flush will cure the problem. any advice on it!!!

MY2015 2.0 TDI CUNA

 

Expansion tank has both stamps, G13 & mit silikat.

11 hours ago, automass said:

Well, G13 means silicates are included in the coolant mixture itself, where as Mit Silicat- they are provided via a silicate bag if I am right. So, in my case, I shouldn't have Mit Silicat in my expansion tank. I never had coolant flushed. Just wondering if coolant flush will cure the problem. any advice on it!!!

So the whole reason why Skoda / VAG put these silicon bags into the coolant tank was to try and make the Coolant - "Coolant for Life" - if I remember rightly - sometime between 2015 and 2017.  The term "coolant for life" got dropped very quickly, but the silicon bag was there to remove excessive moisture in the coolant.  In the meantime, VAG had gone from G12+ to G13 - which was meant to compliment the minimal servicing requirements.  G13 got pulled (I think) due to environmental concerns and it got replaced by the current mix we all use today called G12evo.  Skoda will still recommend a coolant replacement every 5 years though, so the whole silicon bag debacle is one of those issues where VAG chalked it up to experience.  I know of Skoda dealers who's techs remove the silicon bag if they see it....other's leave it.  Its a mess.  In short though, I recommend removal of the silicon bag due to the fact that the bag splits. 

 

In answer to this question from automass, if your coolant is over 5 years old, a coolant flush is not going to hurt.  The coolant can weaken, if you had silicon bag in your header tank (and it split and you didn't get a flush done at the time) then a coolant flush followed by fresh G12evo will definately help.

4 minutes ago, varaderoguy said:

but the silicon bag was there to remove excessive moisture in the coolant

You know coolant is roughly 50% water, right?

 

Edited 22 January, 20251 yr by Breezy_Pete

1 minute ago, Breezy_Pete said:

You know coolant is roughly 50% water, right?

Excessive moisture and also as a lubricant (sorry I missed out that bit). 

I would also correct an earlier statement about G12+ - that should have been G12++.

 

The helpful chart gives a better timeline.

 

8 minutes ago, varaderoguy said:

Excessive moisture and also as a lubricant (sorry I missed out that bit).

Mit Silikat refers to silicate  not hygroscopic silica, they're different compounds.

 

 

Edited 22 January, 20251 yr by PetrolDave

Thanks @PetrolDave - I've correctly what I said earlier (everyday/schoolday etc)  Sorry if anybody was confused.