Hi Guy could you please help me my Octavia  2016 model heater blowing on both sides cool air on hi temperature mode. Today I flushed it and put new purple coolant from euro car Parts still getting cold air so please help me?????

How did you do the coolant change?  Did you also remove the Silica teabag in the header tank at the same time.

 

You should be using G12evo or G13 ready mixed coolant (Red) for the car.  If there is no heat from the heater, then you may have either a blocked matrix from the silica tea bag - or you have a failed thermostat (what is the car temperture doing?)

You also might have a air lock (did you expel all the air from the cooling system??)

No mate I just unscrew the both radiator bottom hose and drain it and flush  4 times but it’s very dirty please look the video I have attached 

With so much gunk it could be blocked heater or thermostat. @varaderoguy asked you about the car temp, is it reaching the normal operating temperature and is it keeping it while driving?
 

If it’s the heater core, you may want to try running the car for 15 minutes on 8-10% citric acid water mix while heating is set to max. Then flush few times with distilled water and try the heating. Mercedes has citrix acid radiator flush which is basically the same.

Thanks mate for your help.I flushed 4 times with de-ionised and I bought 2 bottles of Holts speed flush,So the final flush it’s Cristal clear and I mix the coolant G13 purple with de-ionised water and done the air lock by opening the top hoses on the reservoir tank and I can’t find the silicon tea bag on it. Still it’s not getting hot air but the car temperature reach on 90 degrees with in few minutes it’s seem normal..I changed new pollen filter also..Maybe it’s the thermostat has some trouble is that easy to change I don’t know where it’s in my car some YouTube videos showing it’s under the air filter box,How we can find if the thermostat not working properly????

You could try re-callibrating the system. There's a youtube vid in this link.

 

 

If the temp gauge gets to 90 quickly & stays there, the thermostat will be ok.

 

This presumably is the EA288 engine, so has an electric auxiliary  coolant pump to supply the heater. 

 

That might have failed or the heater matrix might be clogged up.

What is the part number on the coolant tank.

Some of the earlier tanks had the silicate in a tube or bag between two walls, so it doesn't just float there like a tea bag in some of the later ones.

 

That material looks like rust, but do the metal bits stick to a magnet?

Was it sandy in texture as that might give a clue to other possible causes.

 

There's a lot of aluminium in the system also, so you do have to be careful on using the correct coolant too.

 

I have just purchased an Octavia 3 a week ago, and have noticed something similar; regardless of the temperature I set (not Auto), the middle 2 vents continuously blow out cold air.

I have reset the system, which seemed to resolve this for the duration after the reset until the next day, when it went back to blowing out cold again.

I'm assuming this is a fault, or am I missing something in the settings?

46 minutes ago, Noms said:

I have just purchased an Octavia 3 a week ago, and have noticed something similar; regardless of the temperature I set (not Auto), the middle 2 vents continuously blow out cold air.

I have reset the system, which seemed to resolve this for the duration after the reset until the next day, when it went back to blowing out cold again.

I'm assuming this is a fault, or am I missing something in the settings?

Id take it back to the garage where you got it from and let them take a look.

Edited 11 March, 20215 yr by Ecomatt