No heat

[Stook]

A few years ago I had an issue with no heat from the vents. Just cold air. The Skoda dealer charged me about £500 for a flush using their specialised equipment. There are other similar posts on  here.

 

Today, I am experiencing the same problem with no heat from the vents.

 

Last week, water pump / timing belt were replaced but there was definitely hot air afterwards.

 

I've pulled away the panel in the passenger footwell and felt both of the pipes going into the heater matrix when the engine was hot. They were too hot to touch to hold which suggests plenty of hot water is going in and out.

 

Anyone have any ideas what might be causing the issue? Can a heater matrix have hot water going in and out but still be clogged?

 

 

[varooom]

You should let us know which system you have, electronic climate control might just need a reset of the flaps to change the mix of hot/cold air that passes over the heat exchanger.

A picture can say a thousand words.

[Stook]

1 minute ago, varooom said:

You should let us know which system you have, electronic climate control might just need a reset of the flaps to change the mix of hot/cold air that passes over the heat exchanger.

A picture can say a thousand words.

 

Electronic climate control. I thought that all MK3 had these?

[varooom]

Just now, Stook said:

Electronic climate control. I thought that all MK3 had these?

You are probably correct, but I prefer not to assume 😆

 

Not sure of the button combo, but someone will be along, or hit the google.

If that does not help, then you may have a stuck flap, so you need to code read the car to find out which one(s) is/are stuck.

[Stook]

1 minute ago, varooom said:

You are probably correct, but I prefer not to assume 😆

 

Not sure of the button combo, but someone will be along, or hit the google.

If that does not help, then you may have a stuck flap, so you need to code read the car to find out which one(s) is/are stuck.

 

This resetting of flaps rings a bell from last time. I'll see what I can find out from google.

 

Other thing I thought is air lock. It's possible that the air has circulated since the belt/pump replacement and now trapped in the matrix. I've maybe only done about 50 miles since. I did notice that the coolant level was slightly below the min so there has been some air in the system after the replacement or, I guess it's possible that there is now coolant leaking from faulty water pump...however, I am not sure if that would affect the heating if level is just below the min.

[varooom]

 

Looks like holding down Face direction and AC button

[Stook]

Thanks. I found similar youtube and took for a drive. That didn't help. I did however notice that one of the pipes going into the matrix is actually a lot hotter than the other which suggests a blockage in the matrix. The coolant isn't particularly healthy looking either despite being replaced last week. So, 4 years and 30k miles after Skoda dealer fixed this, the problem seems to have returned.

[varooom]

That silicate stuff is a nightmare if that has come back again.

Hopefully you can sort it out, might pay to scan the car in case the flap is stuck and registering as such in a diag scan.

 

Best of luck with it.

[Stook]

Thanks. Really not impressed. A car should not have this problem after 45k and 75k miles.

[J.R.]

2 hours ago, Stook said:

I did however notice that one of the pipes going into the matrix is actually a lot hotter than the other which suggests a blockage in the matrix

That is what is supposed to happen with a heat exchanger!!!!! It depends on what you consider "a lot hotter" to be though.

 

It does sound like the blending flap not operating, I kinda hope for your sake that is the case.

Edited 27 December, 2022 by J.R.

[Stook]

17 minutes ago, J.R. said:

That is what is supposed to happen with a heat exchanger!!!!! It depends on what you consider "a lot hotter" to be though.

 

It does sound like the blending flap not operating, I kinda hope for your sake that is the case.

 

Thanks for the reply. 

 

One pipe I couldn't touch for more than a second. The other pipe I could touch without having to remove it.

 

I wouldn't expect that much heat to be lost even if I was getting full heat through the vents.

 

I've seen a video on youtube where a guy replaces the heater matrix on what looks like a 13 plate Mk3. That's when they came in I think. It didn't look too difficult.

 

Also, this thread explains the replacement so I don't understand the crazy costs quoted. I know the proper flush is about £500 but the matrix and a couple of hours work shouldn't be more than a couple of hundred quid. I think that the mk3 required the dashboard to be removed.

 

 

 

 

One difference between this thread above and mine is that luke warm water is mentioned whilst mine is piping hot on one of the pipes going into the matrix. 

 

[Stook]

15 hours ago, J.R. said:

That is what is supposed to happen with a heat exchanger!!!!! It depends on what you consider "a lot hotter" to be though.

 

It does sound like the blending flap not operating, I kinda hope for your sake that is the case.

 

I've just done a 10 mile drive. The 2 pipes going through the bulk head were at different temperatures. One was hot to hold. The other was too hot.

 

The metal pipes going into the matrix are both very hot to touch.

 

To me, this suggests that the hot water is going in to the matrix and leaving it at a slow rate with little pressure. By the time it's pushed through the bulkhead it's has cooled down significantly.

 

I've also notice that the expansion tank has Mit Silikat on it. Looks like last time I had this issue 4 years ago they fixed it using the same part that likely caused the issue in the first place...

[J.R.]

Oh merde! I hope its not Groundhog day

[nickytheshaft]

Phew, you all stressed me with this silicate bag. I just got mine out. 77000km. It was not Burt but a side is all Black. I managed to get it out without removing the overflow bottles but drained it in cases the bag burst.

[Stook]

2 hours ago, nickytheshaft said:

Phew, you all stressed me with this silicate bag. I just got mine out. 77000km. It was not Burt but a side is all Black. I managed to get it out without removing the overflow bottles but drained it in cases the bag burst.

 

Hopefully I've saved you a lot of money!! 🤑

[nickytheshaft]

1 hour ago, Stook said:

 

Hopefully I've saved you a lot of money!! 🤑

Hell yeah 😬

[coley8978]

How when