No Hot Air in Vents HELP 😭

[as1890]

Hello,

I'm wondering if someone can help or advise me.

We have a Seat Leon and for the past year or so we have no hot air from the vents no matter what combination we use 1/2/3/4 etc

There is air coming out just no hot air. Air con works fine but currently have temps of -2/-3 so need some heat.

I've been told it could be a heating matrix, coolant issue and a few other problems.

Next issue is that the cost I've been told it it's a heating Matrix it could cost upto €2000 by the main dealer.

Another person informed me an auto electrician may need to look at it.

I'm completely lost, don't know where to start is it big job or small job or what.

I've had the car on 20+ long runs 2 hours or more still not a puff of hot air.

Any help would be appreciated

 

[BillyCool]

Have a read of this:

Coolant and heating issues

Hey Guys, Got a low coolant warning this morning on my 2017 2.0 tdi 184 FR it was -5°c. On my way to pick up some coolant I noticed the heaters weren't working very well. After topping up the heaters got worse cold on the passenger side warmish on mine, but only at lower fan speeds and temps...

www.seatcupra.net

If you also search "heater matrix" on the forum you'll find several discussions about it.

Is your car petrol or diesel?

 

[as1890]

Have a read of this:

Coolant and heating issues

Hey Guys, Got a low coolant warning this morning on my 2017 2.0 tdi 184 FR it was -5°c. On my way to pick up some coolant I noticed the heaters weren't working very well. After topping up the heaters got worse cold on the passenger side warmish on mine, but only at lower fan speeds and temps...

www.seatcupra.net

If you also search "heater matrix" on the forum you'll find several discussions about it.

Is your car petrol or diesel?

Diesel

 

[BillyCool]

Diesel

Then it could well be your heater matrix.

Depending on how confident you are, you could do it yourself and save a fortune. Someone else jsut got their local garage to do it for about £400, which is good.

 

[as1890]

Then it could well be your heater matrix.

Depending on how confident you are, you could do it yourself and save a fortune. Someone else jsut got their local garage to do it for about £400, which is good.

Thank you.

Can you answer this for me, does the heating matrix require replacement or does it get flushed? I'm hearing different things online some posts say it gets flushed others say bite the bullet and replace matrix.

A well regarded local guy near my work has a fairly good reputation I'll try him tomorrow

 

[BillyCool]

Some people have successfully flushed them out and bought themselves some time, but ultimately they will block up again and they usually need replacing. For me, it's a bit of a false economy but you are welcome to try it. A successful flush usually restores about 50% functionality, it's never fully cleaned out.

I tried to flush mine out once I'd removed it and got a lot of debris out of it. If you blow through one of the openings, you still get a lot of resistence. It's only when you blow into a new one that you realise how blocked the old one was still was. I cleaned mine with all sorts and it was still probably less than 50% effective.

Personally, I see no real benefit in flushing and I don't think it's really worth the effort. For €90 I got a matrix and fitted it myself in about 2 hours. I appreciate that if you have been quoted €2000 to replace the matrix, a flush may be considered a viable option.

If you do replace the matrix, I would advise not to use a dealer. They will want to remove the dash and that's why it costs so much.

It's entirely up to you. I would imagine that at some point you'll still end up with a new matrix, whether you try flushing or not.

 

[SuperV8]

Flushed my matrix 4 or 5 times (easy job to remove) - hoping it would last longer each time I flushed - but it didn't - in the end changed the matrix and it's been perfect for a few years now. Think of flushing your matrix as a temporary fix.

Flush your cooling system first - then install a new matrix. You don't want your nice new matrix blocking up again from crud in your cooling system!

 

[Sham]

Hi

I have a similar issue i have a 1.6tdi seat Leon 2015 and recently had a Cambelt and water pump change costing £800!!! Prior to that the heaters used to blow out hot air most of the time when the car was warmed up but someitmes wouldn’t. But now since the cold weather it constantly blows ice cold air even after a long drive and on motorways when the engine oil n coolant is at 90 degrees. The ac works brilliantly might I add lol it’s the only way to clear the windscreen as on hot it don’t do nothing at all to clear it.
I have taken the silica bag out of the tank myself and it was not burst so don’t think it’s blocked the heater matrix up. My coolant levels are correct and it’s not dropped recently. It did a few months ago and I topped it up twice since then it’s been stable.
someone suggested there could be a leak and to use K Seal ? As I get water dripping into the drivers footwell when I have the footwell vents on.
any suggestions or ideas would be greatly appreciated sorry for the long winded post guys. Tried to get as much info in as possible. I can’t really afford to spend loads on it after the recent Cambelt change.

 

[Sham]

Hi

I have a similar issue i have a 1.6tdi seat Leon 2015 and recently had a Cambelt and water pump change costing £800!!! Prior to that the heaters used to blow out hot air most of the time when the car was warmed up but someitmes wouldn’t. But now since the cold weather it constantly blows ice cold air even after a long drive and on motorways when the engine oil n coolant is at 90 degrees. The ac works brilliantly might I add lol it’s the only way to clear the windscreen as on hot it don’t do nothing at all to clear it.
I have taken the silica bag out of the tank myself and it was not burst so don’t think it’s blocked the heater matrix up. My coolant levels are correct and it’s not dropped recently. It did a few months ago and I topped it up twice since then it’s been stable.
someone suggested there could be a leak and to use K Seal ? As I get water dripping into the drivers footwell when I have the footwell vents on.
any suggestions or ideas would be greatly appreciated sorry for the long winded post guys. Tried to get as much info in as possible. I can’t really afford to spend loads on it after the recent Cambelt change.

Oh forgot to mention after the garage changed my timing belt I asked them if the old one was work out? they told me it wasn’t the original and it had already had a change at some point so basically didn’t even need again yet !!!! I only got it done as I didn’t know if it had bee. Done and didn’t want to risk it going as car is in 100k now I got it on 97k and there was no record in the service book or receipts got from a dealer. This is why I don’t trust garages !

 

[Sham]

Flushed my matrix 4 or 5 times (easy job to remove) - hoping it would last longer each time I flushed - but it didn't - in the end changed the matrix and it's been perfect for a few years now. Think of flushing your matrix as a temporary fix.

Flush your cooling system first - then install a new matrix. You don't want your nice new matrix blocking up again from crud in your cooling system!

Can u point me to a step by step guide on how to flush the cooling system please pal? Would be much appreciated as I’m not the best DIYer. But I have to give it a try before forking out to a garage for a heater matrix I might not need.

 

[Sham]

Hello,

I'm wondering if someone can help or advise me.

We have a Seat Leon and for the past year or so we have no hot air from the vents no matter what combination we use 1/2/3/4 etc

There is air coming out just no hot air. Air con works fine but currently have temps of -2/-3 so need some heat.

I've been told it could be a heating matrix, coolant issue and a few other problems.

Next issue is that the cost I've been told it it's a heating Matrix it could cost upto €2000 by the main dealer.

Another person informed me an auto electrician may need to look at it.

I'm completely lost, don't know where to start is it big job or small job or what.

I've had the car on 20+ long runs 2 hours or more still not a puff of hot air.

Any help would be appreciated

Just an update have let the engine run on idle to get upto temp and my heaters are giving out mildly warm air on low setting upto 3 if I turn up higher then just starts blowing out really cold air sk it seems like mine is a blockage in the system and hopefully a few flushes will sort it out. Ib removed the silica bag already. Il let u know how I get on.

 

[Walone]

Just an update have let the engine run on idle to get upto temp and my heaters are giving out mildly warm air on low setting upto 3 if I turn up higher then just starts blowing out really cold air sk it seems like mine is a blockage in the system and hopefully a few flushes will sort it out. Ib removed the silica bag already. Il let u know how I get on.

I would suggest checking the temperature of the hoses going through the bulkhead to see if they are both hot, with the heater fan OFF the temperatures should be similar, with the fan on full blast I would expect one of the hoses to be cooler than the other.

 

[BillyCool]

Hi

I have a similar issue i have a 1.6tdi seat Leon 2015 and recently had a Cambelt and water pump change costing £800!!! Prior to that the heaters used to blow out hot air most of the time when the car was warmed up but someitmes wouldn’t. But now since the cold weather it constantly blows ice cold air even after a long drive and on motorways when the engine oil n coolant is at 90 degrees. The ac works brilliantly might I add lol it’s the only way to clear the windscreen as on hot it don’t do nothing at all to clear it.
I have taken the silica bag out of the tank myself and it was not burst so don’t think it’s blocked the heater matrix up. My coolant levels are correct and it’s not dropped recently. It did a few months ago and I topped it up twice since then it’s been stable.
someone suggested there could be a leak and to use K Seal ? As I get water dripping into the drivers footwell when I have the footwell vents on.
any suggestions or ideas would be greatly appreciated sorry for the long winded post guys. Tried to get as much info in as possible. I can’t really afford to spend loads on it after the recent Cambelt change.

Just because you have removed the silicate bag does not mean your matrix is not blocked. There is also an issue with casting sand blocking up the matrix.

I would absolutely NOT add K Seal or similar. Some of the coolant pipework (inc. the matrix) have very fine channels and any sort of sealant could actually make the issue far worse.

The water into the footwell - is this water or coolant?

 

[SuperV8]

Can u point me to a step by step guide on how to flush the cooling system please pal? Would be much appreciated as I’m not the best DIYer. But I have to give it a try before forking out to a garage for a heater matrix I might not need.

Have a search on here for leon workshop manuals - they show the official coolant flush procedure. It's not for the faint hearted though as there are many one way valves and coolant circuits each which need blocking off and water flushing through each circuit! and then vacuum filling!
People on here have reported just dropping the bottom rad hose (usual coolant flushing technique) and flushing water through the main coolant circuit has worked for them.
Does sound like your matrix is partially blocked, but could also be trapped air from the coolant pump change?.
It's NOT just silicate which can block the matrix - but also just detritus from an infrequently changed coolant can block the narrow matrix passages.
If you are 'up for' flushing your cooling system - then sounds like you are 'up for' changing you heater matrix! Quite simple - remove a few under dash trim panels/glovebox/blower motor - and the heater matrix slides out to the passenger footwell. Undo the 2x pipes and collect something like 0.5L of coolant.

edit#
DON'T USE K-SEAL or similar!

 

[Sham]

I would suggest checking the temperature of the hoses going through the bulkhead to see if they are both hot, with the heater fan OFF the temperatures should be similar, with the fan on full blast I would expect one of the hoses to be cooler than the other.

Will give that a try thanks for the advice, much appreciated

 

[Sham]

Have a search on here for leon workshop manuals - they show the official coolant flush procedure. It's not for the faint hearted though as there are many one way valves and coolant circuits each which need blocking off and water flushing through each circuit! and then vacuum filling!
People on here have reported just dropping the bottom rad hose (usual coolant flushing technique) and flushing water through the main coolant circuit has worked for them.
Does sound like your matrix is partially blocked, but could also be trapped air from the coolant pump change?.
It's NOT just silicate which can block the matrix - but also just detritus from an infrequently changed coolant can block the narrow matrix passages.
If you are 'up for' flushing your cooling system - then sounds like you are 'up for' changing you heater matrix! Quite simple - remove a few under dash trim panels/glovebox/blower motor - and the heater matrix slides out to the passenger footwell. Undo the 2x pipes and collect something like 0.5L of coolant.

edit#
DON'T USE K-SEAL or similar!

Thanks for the advice pal. Yeh I was thinking that using k seal would surely clog it up even more and that’s just guna make it worse. It’s just water dripping into the drivers footwell. When had the Cambelt they had a look and said was ac pipe out of place and they sorted it. But still get a bit when the blowers are set to footwell had a look myself and it drips from behind the vents and onto the clutch pedal.
yeh I’m not confident enough to do the full flush myself in depth but would have a go at the simpler one lol. If that makes a difference then happy days..

 

[Sham]

Have a search on here for leon workshop manuals - they show the official coolant flush procedure. It's not for the faint hearted though as there are many one way valves and coolant circuits each which need blocking off and water flushing through each circuit! and then vacuum filling!
People on here have reported just dropping the bottom rad hose (usual coolant flushing technique) and flushing water through the main coolant circuit has worked for them.
Does sound like your matrix is partially blocked, but could also be trapped air from the coolant pump change?.
It's NOT just silicate which can block the matrix - but also just detritus from an infrequently changed coolant can block the narrow matrix passages.
If you are 'up for' flushing your cooling system - then sounds like you are 'up for' changing you heater matrix! Quite simple - remove a few under dash trim panels/glovebox/blower motor - and the heater matrix slides out to the passenger footwell. Undo the 2x pipes and collect something like 0.5L of coolant.

edit#
DON'T USE K-SEAL or similar!

Forgot to ask the water pump change I had done if that has caused air bubbles in the system surely I can take it back to them and ask them to rectify it ??

 

[BillyCool]

Forgot to ask the water pump change I had done if that has caused air bubbles in the system surely I can take it back to them and ask them to rectify it ??

The system is supposed to self-bleed, so any air should work its way out of the system.

This is a guide that I've wrriten that might help with a matrix change. You can see if you fancy giving it a go.

 

[as1890]

Update on this folks.

Car going to Main Dealer in Cork, Ireland Monday. Timing belt had to be done and getting a coolant flush which service tell me will fix my issue with no heat. In the last 2 weeks I'm getting heat for 5-10 seconds after a 15 minute drive, turn off blower for a minute and back on again for 10 seconds for mild heat.

A local mechanic said it would be between €600 - €700 to fix. The main dealer said around €1000 so it's going to main dealer anyway so we're going to go with them. Local mechanic said he couldn't guarantee it would be fixed after spending €700

 

[SuperV8]

Update on this folks.

Car going to Main Dealer in Cork, Ireland Monday. Timing belt had to be done and getting a coolant flush which service tell me will fix my issue with no heat. In the last 2 weeks I'm getting heat for 5-10 seconds after a 15 minute drive, turn off blower for a minute and back on again for 10 seconds for mild heat.

A local mechanic said it would be between €600 - €700 to fix. The main dealer said around €1000 so it's going to main dealer anyway so we're going to go with them. Local mechanic said he couldn't guarantee it would be fixed after spending €700

Coolant flush will not fix your heater matrix - might work temporarily. The fix is a new heater matrix.

I would have the dealer do your cambelt - and coolant flush (which they should be doing anytime they disturb the coolant system anyway!) and then find a someone who can change the heater matrix - easily under 2 hour job.

A new matrix is probably around €150? (they cost more in the winter!)
They are a simple change - from the side of the dash. Drop the glovebox out and blower motor, tunnel side trim and its there - couple of clamps and she's free!