[Jekyll700]

So my son's Corsa 1.2 SXi has a lukewarm heater and as he is even less practical than me I have so far changed the thermostat, replaced the heater motor resistor and flushed out the heater matrix.

We now get lukewarm air at best, which whilst a step forward is still useless in the winter months. So should I flush the matrix again or get a new one? Or is there something else I am missing?

Thanks,

 

[ozsubrosa]

Welcome to CCUK. From the title, it looks like you've read around; I haven't had this problem but most of the time it's the heater matrix. A more thorough flushing can sort it out but sometimes it can take a replacement matrix because it's not a brilliantly done piece of kit.

Others will come in with more first hand experience.

 

[jewels]

what did you clean it with? There are radiator cleaners, or try with kh7 gasoline etc, I would also use hot water with the radiator cleaner, and if you can leave it for a while to soften the crap it would be better, in the worst case I would see if they clean them by ultra sound , or send the radiator to clean

 

[Jekyll700]

thanks - sounds like it would be easier to just change the matrix

 

[jewels]

Some photos would not hurt, especially as the radiator hooks on the pipes, I think it loses me there

 

[corsaz22se]

A new matrix is not expensive and it can be change fairly easy. You could try removing it and soaking in boiling water then flushing. But at around £30-40 for a new one its not much to replace.

 

[Jekyll700]

so I was planning to order a new matrix and change it, but today my son started the car and had a sudden water leak onto the passenger side floor and a simultaneous fizzing of the new fan motor resistor

seems as though water was coming through the heater pipework - anyone know whether this will be coming from the matrix or the bulkhead?

 

[jewels]

or to see if it got stuck and with the pressure it released, that until you see it is to give a blind opinion, the pipe is difficult to break, I would say that it loses due to the connection with the radiator by pressure is the weakest point

 

[corsaz22se]

the pipe work to the heater is on the drivers side (right hand side) behind the plastic panel. if these pipes leak or the matrix fails the coolant will run out in to the right hand foot well first not the fan motor as that is higher up.
It is possible the seals on the bulk head have gone and the drain holes for the bulk head are blocked, there is a drain under the batter tray and another near the brake servo on right hand drive cars. they both exit in to the engine bay.

 

[jewels]

that in Spain many get stuck with sheets of mud and others and in opel it is the first thing they tell you to check

 

[Jekyll700]

thanks both, but the drains on the bulkhead are clear - although I know that is no guarantee of avoiding a leak through the seal

going to have a poke around as I need to understand how water gets inside the heater vent on the passenger side

 

[jewels]

With the issue of the servo bulkhead water, weren't some affected also by the air filter inlet? If not, what you can do is dry the area well and stain it with talcum powder? what is used for baby diapers? And when it gets wet, it cleans them so you know where it goes

 

[corsaz22se]

Also do you have A/C? there is a drain form this on the bottom of the bulk head near where the gear shifter rod come out, these block up over time.
If not it will be the seal on the pollen filter housing to bulk head as it is just a foam seal.

 

[Jekyll700]

Yes, the car does have AC - will try to find the drain for that

Still not sure where water can get inside the blower pipes to ruin the fan resistor though - would this be from the heater matrix, or the bulkhead seal?

 

[jewels]

unopened and seeing it is a lottery Knowing that the radiator gives you problems and that all corsa leaks through the bulkhead of the pedals, you are talking at a 50% chance

 

[Jekyll700]

so in an attempt to replicate the problem we poured water into the bulkhead area (five watering cans worth!) and got no leakage into the car

now thinking leak must be from heater matrix or possibly a/c

am I missing anything?

 

[corsaz22se]

Water can get inside the heater from the bulk head seal or from the A/C condenser.
Are you loosing coolant? does the water in the heater fan smell like coolant?