HELP ME PLEASE!!!

CardiffFR150

Active Member
Jan 5, 2021
78
20
Cardiff
Hi guys,

I have a 2014 Leon FR (mk3). I need to remove the heater matrix. I’ve been advised that this can be done without removing the dashboard. Is this true? Apparently it can be accessed and removed from the passenger footwell area. Any advice please guys?
 

Walone

Active Member
Feb 10, 2016
1,533
418
Near Heathrow
There is a guide somewhere on the forum posted by a member who has done it, but I can't find it at the moment, try searching for 'No heat from vents' or something like that.
 
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CardiffFR150

Active Member
Jan 5, 2021
78
20
Cardiff
let us know how you get on

Hi. I’ve been on the phone to a mate and he’s confirmed that the heater matrix is definitely accessible via the passenger footwell. Here’s a video of the same job being done on a 2013 Skoda Octavia which has the exact same layout as the mk3 Leon.

Im going to attempt to change mine tomorrow with a bit of luck lol. Seems pretty straight forward.
 

andycupra

status subject to change
i don't think the octavia in the video had a leak, - likely the usual VAG issue of the coolant low level alarming when the ambient temperatures drop. too many people over-react to this, when a small top up fixes it in 90% of cases as it is usually simply a slightly lower level due to being colder. simple as that.

Job looks pretty reasonable for a heater matrix replacement.
PS - also nice he had a couple of mistakes, - means you don't make the same!
also, how can you remove a heater matrix as it may have been blocked and not run some water through it to see if it was! - although if he really did a good job of flushing the system that fact the coolant was still pink suggests it was blocked - as well it being fixed :)
 
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BillyCool

Active Member
Jan 16, 2020
645
244
Leicestershire, UK
Hi guys,

I have a 2014 Leon FR (mk3). I need to remove the heater matrix. I’ve been advised that this can be done without removing the dashboard. Is this true? Apparently it can be accessed and removed from the passenger footwell area. Any advice please guys?

I replaced mine in March following the above video in about 3 hours and that included taking my time.

I've sent instructions to about 3 others members on the same subject so drop me a DM if you need any help with sourcing your matrix, tools, fitting, photos etc.

The matrix is never usually fully blocked but has restricted water flow due to the combination of possible silicant gel from the split bag in the header tank and casting sand from the engine block. You can try to flush it out (I tried 3 times) but compared to a new one, it's never as good.
 
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SuperV8

Active Member
May 30, 2019
1,317
578
Try looking here No heat from vents | SEATCupra.net Forums from post number #16
That about covers it - BUT you also need to undo the screws holding the blower motor in and drop the blower motor.

This is how I flushed out my matrix, kept doing this until the water in the bucket was virtually clear.
Worked fine for me, lovely hot air after - the problem will be it depends on how much sediment you have in circulation in your coolant system? This will be unknown and seems to vary from car to car. Mine blocked twice again, each time longer between blocking (months rather than weeks), but I can now get the matrix out in less than 30 mins!.
I have since done my timing belt/water pump and flushed/replaced my coolant/thermostat (keeping my original cleaned heater matrix)

edit:
Also to add - you don't need to drain your coolant - just be prepared (plastic sheet/cloth/shallow tray) to collect a small amount of coolant when you release the lower pipe . No more coolant comes out. Probably only a can of coke's worth.
 
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CardiffFR150

Active Member
Jan 5, 2021
78
20
Cardiff
I replaced mine in March following the above video in about 3 hours and that included taking my time.

I've sent instructions to about 3 others members on the same subject so drop me a DM if you need any help with sourcing your matrix, tools, fitting, photos etc.

The matrix is never usually fully blocked but has restricted water flow due to the combination of possible silicant gel from the split bag in the header tank and casting sand from the engine block. You can try to flush it out (I tried 3 times) but compared to a new one, it's never as good.

Thanks a lot mate. I’ve been at it all day I’m about to put the matrix back in. I’ve tried to wash it out as much as possible. It seems to now be clear after a bit of muck came out. Fingers crossed! It’s bloody freezing in Wales lol
 

CardiffFR150

Active Member
Jan 5, 2021
78
20
Cardiff
That about covers it - BUT you also need to undo the screws holding the blower motor in and drop the blower motor.

This is how I flushed out my matrix, kept doing this until the water in the bucket was virtually clear.
Worked fine for me, lovely hot air after - the problem will be it depends on how much sediment you have in circulation in your coolant system? This will be unknown and seems to vary from car to car. Mine blocked twice again, each time longer between blocking (months rather than weeks), but I can now get the matrix out in less than 30 mins!.
I have since done my timing belt/water pump and flushed/replaced my coolant/thermostat (keeping my original cleaned heater matrix)

edit:
Also to add - you don't need to drain your coolant - just be prepared (plastic sheet/cloth/shallow tray) to collect a small amount of coolant when you release the lower pipe . No more coolant comes out. Probably only a can of coke's worth.

Hi thanks for your information. Really does help. I’ve had my matrix out for a few hours flushing it out. I had a new bottle of coolant so I decided to flush the system at the same time. I’m about to put it all back together. I really hope it works! I’ll keep you updated pal.(y)
 
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BillyCool

Active Member
Jan 16, 2020
645
244
Leicestershire, UK
LOL! You can try the `trumpet test` by blowing through one of the holes. It should be completely unrestricted. My old one still had some resistance and it was only when I got the new one that I realised how clogged up it was even after `cleaning`. You can keep cleaning and replacing and will probably work for a while but personally for €80 I'd just rather fit a new one.

Just be careful not to damage it when you put it back in. The fins are quite fragile.
 

BillyCool

Active Member
Jan 16, 2020
645
244
Leicestershire, UK
Hi thanks for your information. Really does help. I’ve had my matrix out for a few hours flushing it out. I had a new bottle of coolant so I decided to flush the system at the same time. I’m about to put it all back together. I really hope it works! I’ll keep you updated pal.(y)

Flush which part of the system?
 

CardiffFR150

Active Member
Jan 5, 2021
78
20
Cardiff
Flush which part of the system?

I took the bottom hose off the radiator and disconnected the inlet/outlet pipes going through the firewall. I then used water to flush it through via the expansion tank.

I’ve put it all back together and not getting no heat:( Even worse now because it’s overheating when I drive!! Not loosing coolant though. Both the inlet and outlet pipes that are attached directly to the matrix (inside the passenger footwell) are freezing cold! Not warming up at all! Also when I had the matrix out, I could blow through it fairly easy. Took a bit of a blow mind. I’ve had enough today lol. Any advice mate? Cheers(y)
 

BillyCool

Active Member
Jan 16, 2020
645
244
Leicestershire, UK
The cooling system is quite complex and effectively has 3 parts to it. The only way to properly bleed the system is get SEAT to do it with their magic kit.

I did much the same to you and dumped as much coolant as I could via the rad hose and then filled it back up. The system is prone to air locks/blocks and is meant to self bleed over time. Did you run it with the lid off the expansion tank? Some people go for drive and top it up a few times before the levels sort themselves out.

If your matrix is cold then it's either a mega air lock and/or something else isn't quite right i.e water pump. I had my pump replaced because the stupid electronic widget failed.

I'd try to burp the system a bit and see if you can keep topping it up. The old fashioned way was to squeeze the big hose from the rad to the expansion tank to try and get the air out.

In terms of the water pump - is water being pump back into the expansion tank via the small return pipe?
 

SteveGSXR600K1

Active Member
May 6, 2017
572
187
I took the bottom hose off the radiator and disconnected the inlet/outlet pipes going through the firewall. I then used water to flush it through via the expansion tank.

I’ve put it all back together and not getting no heat:( Even worse now because it’s overheating when I drive!! Not loosing coolant though. Both the inlet and outlet pipes that are attached directly to the matrix (inside the passenger footwell) are freezing cold! Not warming up at all! Also when I had the matrix out, I could blow through it fairly easy. Took a bit of a blow mind. I’ve had enough today lol. Any advice mate? Cheers(y)
Did you do the process of squeezing the pipes, running it up to 90c to open the thermostat, etc, that the guy did at the end of the Octavia video, to bleed any air out of the system?
 
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CardiffFR150

Active Member
Jan 5, 2021
78
20
Cardiff
The cooling system is quite complex and effectively has 3 parts to it. The only way to properly bleed the system is get SEAT to do it with their magic kit.

I did much the same to you and dumped as much coolant as I could via the rad hose and then filled it back up. The system is prone to air locks/blocks and is meant to self bleed over time. Did you run it with the lid off the expansion tank? Some people go for drive and top it up a few times before the levels sort themselves out.

If your matrix is cold then it's either a mega air lock and/or something else isn't quite right i.e water pump. I had my pump replaced because the stupid electronic widget failed.

I'd try to burp the system a bit and see if you can keep topping it up. The old fashioned way was to squeeze the big hose from the rad to the expansion tank to try and get the air out.

In terms of the water pump - is water being pump back into the expansion tank via the small return pipe?

Thanks for replying. I ran the engine whilst topping the coolant up. Gave the pipes a squeeze and the coolant seemed to be flowing through the system. I took the car for a spin and noticed my coolant temperature went through the roof and the fan kicked in!

I checked coolant level and all was ok. I just limped it back to the house. However I’ve just remembered that there was a wired connector beneath the glove compartment which seems to be linked to the blower system which I forgot to plug back in. Not sure if it has anything to do with the cooling system. I’ve attached a pic of the connector (not my pic but same thing)
 

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CardiffFR150

Active Member
Jan 5, 2021
78
20
Cardiff
Did you do the process of squeezing the pipes, running it up to 90c to open the thermostat, etc, that the guy did at the end of the Octavia video, to bleed any air out of the system?

Yep! Even made the same mistake that he did by not fixing the clamp on the matrix pipe properly lol. But yeah mate pretty much followed it step by step. Of course I only attempted to clean my matrix not replace it. One big ball ache when it comes to cooling systems!
 
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BillyCool

Active Member
Jan 16, 2020
645
244
Leicestershire, UK
Thanks for replying. I ran the engine whilst topping the coolant up. Gave the pipes a squeeze and the coolant seemed to be flowing through the system. I took the car for a spin and noticed my coolant temperature went through the roof and the fan kicked in!

I checked coolant level and all was ok. I just limped it back to the house. However I’ve just remembered that there was a wired connector beneath the glove compartment which seems to be linked to the blower system which I forgot to plug back in. Not sure if it has anything to do with the cooling system. I’ve attached a pic of the connector (not my pic but same thing)

I don't know what that does or if it's relevant but not plugging something back in is never wise! ;)

Is it connected now? I'd do that before you drive it again and see how that goes.

Also maybe let it settle overnight and check coolant levels in the morning?
 
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CardiffFR150

Active Member
Jan 5, 2021
78
20
Cardiff
I don't know what that does or if it's relevant but not plugging something back in is never wise! ;)

Is it connected now? I'd do that before you drive it again and see how that goes.

Also maybe let it settle overnight and check coolant levels in the morning?

Yes definitely a silly mistake. It’s not connected yet I’m going to leave it until the morning. Thanks for your advice mate. One last question, how would I know if I had a dodgy water pump??
 
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