Heater only blows cold

[boltonboy]

2009 1.6 HDi 
So the car warms up fine to just under 90 but the air never gets above miserable !
I understand it will be one of two solutions 

1. Thermostat (I’m told this is very unusual)
2. Needs the system bleeding

So assuming it needs bleeding I’m told there’s 2 bleed caps 
One I’ve found to the right under the plastic air pipe and with the expansion tank cap off I’ve undone this one (engine running and cold) it pours out without air bubble stutters,
The 2nd one I’m told is on the heater matrix and is probably where my problem is but I can’t locate it !?
I think it’s to the left of the engine and obviously on the bulkhead but for the life of me cannot see it, I’m even struggling to find a video or image as to its location 

Any help would be appreciated 

Thanks in advance 
Phil

[oilyrag]

Looking into the engine bay from the front the two heater pipes are above and right of the brake master cylinder - they enter a moulded plastic fitting that is attached to the bulkhead. This fitting might also have a bleed cap - looks like a tyre valve cap.
Warm the car up, switch off and open the cap a little - warm water should flow out, taking any bubbles with it.
If you then run the engine and feel the pipes - both should get pretty hot. If not, then it is possible that the matrix is clogged up - it is an involved and big job to change this. Alternatively drain the system and lift the metal clip that holds the pipe connector and wriggle it out - beware there are 2 'O' rings to capture. Then use a hose pipe to flush the matrix out in both directions - do not use mains pressure as it might burst the matrix. Just enter the hose into the fitting and wash out - you may see a dose of rusty water come out. Put vaseline on the connector & O rings and bleed the system.
You do not need to drain the whole system down as the pipes are high on the bulkhead - once disconnected tie the pipes up high and the coolant will stay in the engine/rad.
Another possibility is that the cold/hot air flap system isn't operating via the dashboard dial and you're not getting any hot air as a result.
The matrix is running hot all of the time and the cab temp is controlled by mixing hot and cold air.
Good luck!

[saskak]

What oilyrag has said. I guess the B9 is not too different from the M59, so here are the two bleeding screw valves on my M59: https://www.youtube.com/watch?v=CSmm2SCpPCs

at ~6min is the second bleeding screw valve at the heating matrix.

[boltonboy]

Looking into the engine bay from the front the two heater pipes are above and right of the brake master cylinder - they enter a moulded plastic fitting that is attached to the bulkhead. This fitting might also have a bleed cap - looks like a tyre valve cap.
Warm the car up, switch off and open the cap a little - warm water should flow out, taking any bubbles with it.
If you then run the engine and feel the pipes - both should get pretty hot. If not, then it is possible that the matrix is clogged up - it is an involved and big job to change this. Alternatively drain the system and lift the metal clip that holds the pipe connector and wriggle it out - beware there are 2 'O' rings to capture. Then use a hose pipe to flush the matrix out in both directions - do not use mains pressure as it might burst the matrix. Just enter the hose into the fitting and wash out - you may see a dose of rusty water come out.  Put vaseline on the connector & O rings and bleed the system.
You do not need to drain the whole system down as the pipes are high on the bulkhead - once disconnected tie the pipes up high and the coolant will stay in the engine/rad.
Another possibility is that the cold/hot air flap system isn't operating via the dashboard dial and you're not getting any hot air as a result.
The matrix is running hot all of the time and the cab temp is controlled by mixing hot and cold air.
Good luck!

Thank you so much

[boltonboy]

Thanks a lot

[boltonboy]

What oilyrag has said. I guess the B9 is not too different from the M59, so here are the two bleeding screw valves on my M59: https://www.youtube.com/watch?v=CSmm2SCpPCs

at ~6min is the second bleeding screw valve at the heating matrix.

Thank You

[boltonboy]

Great stuff cheers

[oilyrag]

Meant to add - if the matrix doesn't flush well then thoroughly dissolve a dishwasher tablet in a jug of boiling water and feed this into the matrix and leave for a couple of hours. The tablet contains a mild de-scaler. If more muck comes out when you then flush you can go through the same process until you get clean water out.
My matrix clogged immediately after an MoT - revving the engine for emissions must have shifted some muck, but the above cleared it out and all is warm now!