Hi all, quite new to this forum so if im putting anything in the wrong topic or not using correctly I do apologise.

 

I'm in the midst of changing my heater matrix, I have a 2019 octavia mk3.5 vrs post facelift. I'm looking to replace the matrix as its only blowing cold air however I can't seem to find the correct matrix replacement, the one currently installed has the straight pipes however no matter what parts supplier I look at they only supply the matrix with the bent inlet pipe. I will supply a photo of my situation, any help is appreciated. Thanks.

What happened with the current matrix?  If its blowing cold, its usually a problem with the Silica teabag in the coolant header bottle having split.  This will have put all the silica into the heater matrix and more worryingly potentially block up the coolant channels in the engine block.

 

If this is the case, then you need to flush out the cooling system ASAP.  You only need to replace the heat exhange matrix in the cabin if its leaking.

I've removed the silica bag more of a precaution but I don't think it has split, however the inside of the old matrix doesn't look the best inside however I can't see any silica beads in the matrix/system. From what I've read the matrix is the main reason you get cold air coming through the vents, unless you have another solution. Thanks.

Yeah I have been told heater matrixes fail often regardless of tea bag parties.

 

It also cud be the flaps that control air flow to the heater matrix, but I believe the matrix itself is more common to fail.

The flap motors do also fail as well and it is probably to get the motor changed out.  However, I still don't think the heater matrix itself has failed.  By all means do a coolant flush to make sure there is no dirt in the matrix itself.

 

One thing we are missing though - is a scan via ODBEleven or VCDS to confirm whether the motor flaps have failed or not.

I didn't think about checking the flap motors, when I get in I will hook them up to my scanner and see what comes up, is it a relatively difficult job?

 

Regarding the heater matrix I think I will change out anyway, if anyone has a part number or make that would be great as finding the correct one is what I'm struggling with atm. Cheers

You need to find out if it's a Valeo or Denso system, either might be fitted. Look what brand the blower motor is, if you can access its label.

With that info, and your reg number or VIN, I can probably tell you matrix PN.

Looking at your pic, and the parts catalogue, it looks like those metal pipes aren't part of the matrix, but unscrew/unclamp from it?

On most VAG cars that age, the end of the pipe is a bit convex and the heater matrix inlets are a bit concave. The clamps are a v-band that pushes them together when fitted properly . It can be an utter **** of a job but needs to be done right. 

 

if you think the matrix is gunked up, have you tried disconnecting the pipes in the engine bay side and flushing it out with a hose pipe (or airline if you're a fatalist)?

I have the same heater matrix fitted and I'm also struggling to find the same part.

 

I own a skoda Octavia MK3 68 Reg 1.6 Esate DSG.

 

Blowing only warm air from passenger vent.

 

I have checked with local part shops , also tried TPS & looked online with no luck.

 

Based on my REG , it will bring up a different Heater.

I have been told it may be a later Denso model, 

4 minutes ago, sham16 said:

I have the same heater matrix fitted and I'm also struggling to find the same part.

 

I own a skoda Octavia MK3 68 Reg 1.6 Esate DSG.

 

Blowing only warm air from passenger vent.

 

I have checked with local part shops , also tried TPS & looked online with no luck.

 

Based on my REG , it will bring up a different Heater.

I have been told it may be a later Denso model, 

I have exactly the same situation it's so strange, mine is a 2.0 tsi dsg and whenever I enter my reg or vin number it comes up with a diffent type. I think it is denso as that's the only variant that looks the same as the one currently fitted and the blower is also denso. Just strange that it's impossible to link that matrix to my car anywhere on the Web. I've managed to find one and ebay and I'm biting the bullet and ordering it to see if it fits.

If you're sure it's a Denso system, and you tell me the VIN, I can tell you the matrix part number.

2 hours ago, Breezy_Pete said:

Looking at your pic, and the parts catalogue, it looks like those metal pipes aren't part of the matrix, but unscrew/unclamp from it?

Yeah the pipes disconnect from the matrix using those v-clamps which then leaves to straight ports on the matrix.

Just now, Breezy_Pete said:

If you're sure it's a Denso system, and you tell me the VIN, I can tell you the matrix part number.

My VIN is TMBBU7NE0K0154947. Cheers mate

Or just bite the bullet and take it out far enough to find the part number sticker on it?

2 minutes ago, Lewisyoung said:

I have exactly the same situation it's so strange, mine is a 2.0 tsi dsg and whenever I enter my reg or vin number it comes up with a diffent type. I think it is denso as that's the only variant that looks the same as the one currently fitted and the blower is also denso. Just strange that it's impossible to link that matrix to my car anywhere on the Web. I've managed to find one and ebay and I'm biting the bullet and ordering it to see if it fits.

I ordered off Ebay,  found only 1 seller with the heater I needed , brand NRF but they still.managed to send the wrong one so I will be returning it to tomorrow

2 minutes ago, Breezy_Pete said:

Or just bite the bullet and take it out far enough to find the part number sticker on it?

Tbf I took it out ready to put the new one in only to realise I'd bought the wrong one (I know amateur move) so after alot or cursing I just though the old one back in without checking the part number, serves me for getting in a huff haha

7 minutes ago, Breezy_Pete said:

If you're sure it's a Denso system, and you tell me the VIN, I can tell you the matrix part number.

Sorry I put my vin under the wrong reply, it's TMBBU7NE0K0154947, if you have no luck no worries just thanks for checking.

That VIN for a Denso system gives matrix part number 5WA 819 031. Skoda only want £326 plus VAT retail. 😆

1 minute ago, Breezy_Pete said:

That VIN for a Denso system gives matrix part number 5WA 819 031. Skoda only want £326 plus VAT retail. 😆

Is that it....Great...il go sell my kidney now.....

8 minutes ago, Lewisyoung said:

Is that it....Great...il go sell my kidney now.....

 

11 minutes ago, Breezy_Pete said:

That VIN for a Denso system gives matrix part number 5WA 819 031. Skoda only want £326 plus VAT retail. 😆

From what I can gather after searching that part number and looking at pictures I can confirm that that is unfortunately the one. Thanks for helping mate I'd still be scratching my head otherwise.

I have found this 5WA819031 - 707278 - which i think is NISSENS

 

Cheapest I can find on Ebay

https://www.ebay.co.uk/itm/126916634064?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=JCd5rML7SDq&sssrc=4429486&ssuid=k2rsDVOoTni&var=&widget_ver=artemis&media=COPY

9 minutes ago, sham16 said:

I have found this 5WA819031 - 707278 - which i think is NISSENS

 

Cheapest I can find on Ebay

https://www.ebay.co.uk/itm/126916634064?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=JCd5rML7SDq&sssrc=4429486&ssuid=k2rsDVOoTni&var=&widget_ver=artemis&media=COPY

It might be worth a go tbh, first I think I'm going to ring some scrappers in my area and see if I have any luck.

On 10/02/2025 at 12:04, Lewisyoung said:

Hi all, quite new to this forum so if im putting anything in the wrong topic or not using correctly I do apologise.

 

I'm in the midst of changing my heater matrix, I have a 2019 octavia mk3.5 vrs post facelift. I'm looking to replace the matrix as its only blowing cold air however I can't seem to find the correct matrix replacement, the one currently installed has the straight pipes however no matter what parts supplier I look at they only supply the matrix with the bent inlet pipe. I will supply a photo of my situation, any help is appreciated. Thanks.

I'm just about to do mine, and this looks like like the Valeo one, as the clamps are right on the edge of the heater matrix. Whereas the Denso has protruding pipes which then clamp onto the internal pipework