replacing the heather matrix and heater pump on 2016 octavia

[Alan68]

Hi Folks, 

first post and I am hoping with all the experience here that someone might be able to help. 

I have a 2016 Skoda Octavia 1.6. 

The heater matrix and the heater pump appear to need replacing following an assessment by a local friendly VW and Skoda specialist. 

Has anyone attempted this themselves and if you have what level of success did you have. 

I am considering doing it myself but do not really have the skills and tools. 

But willing to give it a go with an £800+ repair bill if I stick it in the garage. 

Any feedback welcome on this one (Do it/ don't do it/I can do it etc.)  

Thanks. 

[Gaz]

Hello and welcome Alan 

 

There's a YouTube video of someone changing a heater matrix from the passenger side (UK) footwell with minimal disruption to the rest of the dash.

 

Do you mean changing the water pump?  If you do, I believe it's fairly straightforward spanner monkey work.  It's eight years since I gave up (mostly) working on my cars (age and flexibility related), but before that I'd be doing it myself.

 

£800 seems a good price for both.  What symptoms are you experiencing?

 

Is yours petrol or diesel? There's a sticky thread on diesel water pump issues:

 

 

Gaz

 

EDIT: Not the one I'm thinking of, but useful nonetheless:

 

 

Edited 11 February, 2023 by Gaz
Added a video

[Alan68]

Hi Gaz, thank you for your response.  The video is making me anxious just watching it. This is way above my skill and confidence level. 

I will get some more quotes but suspect I may just need to get this done. 

The vehicle is diesel 1.6. I am getting heat into the vehicle but the drivers side is stone cold. I have done the fan recalibration to no effect. 

Mechanic thinks it's the silicone bag added to this models matrix which has broken open and got into the pump and water system. He says it will eventually completely block the matrix. So either repair it or dump it with we buy any car and look for a replacement.  

It's been a great car up to this point.

One of my lifetime favourites as a driver.  

But having to replace matrix and pump at 60k miles is ridiculous for a car of this quality and age.

[TheClient]

A couple of things. If it is the sicate issue. 1. You will probably see some evidence of it inside the coolant expansion tank.

 

2. If your car has the silicate bag in it will be stamped with mitt silicate. 

 

3. I have read quite a few instances accroos  a couple forums of late with matrixes being replaced without resolving the problem indicating the issue was elsewhere.

 

I do not know the 1.6tdi but on ea888 gen 3 for example, as used in the vRS tsi, there is at least one solenoid valve that cab fail and block flow to the heater matrix. 

 

Not saying they're definitely wrong but the other possibilities need exploring and discounting first. There are some cases recorded of the matrix clogging without the silicate bag being the cause as well... 

Edited 12 February, 2023 by TheClient

[SuperbTWM]

There are 3 coolant pumps on these engines so make sure you clarify which one needs replacing.

 

By heater pump I assume its the electric one which is part of the heater micro circuit, not the mechanically driven one.

 

This is a really easy fix so its worth making sure this is working first and maybe trying to back flush the heater matrix before you go ahead and potentially change the heater matrix for no reason.

Edited 12 February, 2023 by SuperbTWM

[Gaz]

19 hours ago, Alan68 said:

I am getting heat into the vehicle but the drivers side is stone cold.

 

Mechanic thinks it's the silicone bag added to this models matrix which has broken open and got into the pump and water system. He says it will eventually completely block the matrix.

 

That you are getting heat in the car suggests to me that the heater matrix is not blocked (or at least not completely blocked).  Heat one side, but stone cold the other is indicative there may be something else going on.

 

Your mechanic needs needs to know, not think, if the silikat bag has split.  If he doesn't 'know', this might be an issue.  It's relatively easy to tell, and reasonable to expect a mechanic to be able to tell rather than guess.

 

As TC has alluded to, if there's a silicate bag in your coolant header tank, the tank will be marked 'Mit Silikat'.  If you take the lid off your header tank and poke a finger in, you should be able to feel the bag, and also tell if it's intact.  If I can do it, anyone can.  Here's one of the more informative threads on it:

 

 

An intact bag is very easy to manoeuvre and wriggle out of the tank.  There are other versions where the silicate can be inside a double skinned tank - you obviously won't find a silicate bag in one of these.  IIRC there have been incidences where what has blocked the matrix is casting sand from when the engine block was made.  Not suggesting this is the case here at all, just that it's not always the silicate bag.  I had a coolant check valve fault (perhaps similar to the solenoid valves TC is referring to), which stopped all heat to the cabin, and ultimately caused my turbo to grenade itself (no cooling to that either), with a rather costly bill to fix it all.

 

Agreeing with TC and Superb, I'd think this warrants further investigation before replacing a matrix which is clearly bringing some heat into the cabin.  Has the car been scanned for fault codes, particularly around warm air delivery?

 

Gaz

 

 

 

[Alan68]

thanks all for your responses. Lots to think about there. I cannot see the Mit Silikat printe anywhere and the header tank for the cooling system was only replaced with the cam belt 2 years ago. 

I will keep delving. Am sure I can dig into this a bit myself and am happy to do the simpler jobs myself. I don't have the kit or the experience for the more complex stuff.