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Heater Matrix removal and replacement guide

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JimB78   
Wed Jan 05 2022, 07:50am
Member No: #58520
Joined: Jul 22 2021
Location: Ireland
I have been having the common problem of no heat on the drivers side vents and a little bit of heat on the passenger side vents, this seems to be widely understood to be down to the heater matrix clogging and the flow returning before it gets all the way around the core, because the matrix in this car is rectangular it seems the drivers side end of it doesn't get warm, hence the cold air from the drivers side vents,

I was hoping to find a step by step "how to" somewhere but no joy, so I decided to do my own


Tools needed,

5.5 m 1/4 inch socket and ratchet
T25 Torx bit socket 1/4 inch
Plastic spudger



Step 1:
Disconnect Battery,

Step 2:
remove lower cover below the glovebox, it is help up by 3 plastic slide rivets you can remove by hand, unplug the footwell light and remove cover.

Step 3:
remove plastic cover to the right side of the footwell, this is held on with one torx screw, it can be pulled off when screw removed.

Step 4:
remove glovebox by unscrewing the 4 torx screws, 3 are on the top of the box as you look into it, and another to the right, then remove the plastic cover over the passenger airbag switch on the upper left part of dashboard that meets the door frame, use the spudger to pry this off, next remove the glovebox light and unplug,
now you can wiggle the glovebox out.

Step 5:
remove electric heater beside heater matrix if you have one, (if not skip this step)
this is fixed with a 5.5mm hex bolt remove this, then unplug the connector and pull out the electric heater

Step 6:
remove heater pipe bracket to the left of the matrix with one 5.5mm hex bolt

step 7:
undo the upper and lower pipe clamps attached to the matrix with your 5.5mm socket,
be ready with towels and a basin to catch spillage and pop off the pipes and drain the pipes and matrix,

step 8:
while that's draining you need to remove the stepper motor above the top pipe as the matrix will not clear it when coming out, this is 3X 5.5mm hex bolts, when its removed you can then push the pipes out of the way and pull the heater matrix out.

Make sure to top up and bleed coolant system afterwards,
Installation is the opposite of removal.



All in all not the worst job ive had to do.

*If a mod can show me how to edit post I can add photos of most of the steps*
will tidy the post up later i just wanted to get it down before i forgot
KDC85   
Thu Jan 06 2022, 02:34pm
Member No: #54649
Joined: Sep 19 2019
Location: Devon
Thanks for this. I wonder if this fix my issue, I have good heat on the passenger side, but the drivers side and the rear are cold.

Did you pull the matix out and replace, or just drain and refill it?

Cheers for your efforts.
JimB78   
Fri Jan 07 2022, 10:33am
Member No: #58520
Joined: Jul 22 2021
Location: Ireland
KDC85 wrote ...

Thanks for this. I wonder if this fix my issue, I have good heat on the passenger side, but the drivers side and the rear are cold.

Did you pull the matix out and replace, or just drain and refill it?

Cheers for your efforts.


hi there, just going on the amount of people who have had these specific issues with heat and how they fixed it, it seems a safe bet,

I pulled the matrix and flushed it but i could see that it was only filling up to about 1/3 of its capacity so i have ordered a new one from citroen,

apparently stock levels for this part are dangerously low, with no sign of them being replenished according to the parts man
 

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