Citroen c5 X7 - cabine heating problem?

[ExOduS442xb]

Hi guys, I have possible problem (still not sure is it normal or a problem) with the cabin heating. As we have entered November the temps have dropped enough for the cabine heating to be used. That said, I just can't get enough heat, no matter which temperature I set.

I have an C5 Exclusive from 2010 with auto a/c. I did noticed that when set to 28 it's a little bit warmer, however it's not warm, more like lukewarm. I've read that some people could not seat in their C5's when set to max temp.

I had BX and C5 mk1 (2002) and setting the heating to max would make you wanna jump into cold river.

Is this normal behavior?

Thanks for all the answers.
Mladen

[Ross_K]

Hi Mladen, I suppose the first things to check would be your coolant level and thermostat. Are these ok?

[ExOduS442xb]

Hi Ross, coolant level is fine, I checked. I am not sure when termostat was changed, but I have no other issues, when engine reaches it's optimal temp it stays at it no matter if you drive slow or fast (more aggressively). If thermostat was the cause, wouldn't there be other symptoms like overheating or engine would not be able reach it's operating temp?

[GiveMeABreak]

It's possible you have a blocked heater matrix or a faulty air mixing distribution motor / flap. Having said that, the flaps and motors on the C5 X7 (MK III) are far more reliable than the MK I or MK II, so I would be looking to get the coolant system checked, possibly flushed out and changed.

[ExOduS442xb]

Thanks Marc, I am not sure I understand how could coolant cause the problem if engine reaches it's operating temperature?

Can I ask does it become very hot in your C5 if you set temp to max?

Thanks,
Mladen

[GiveMeABreak]

What can happen is the heater matrix can become blocked up, which restricts the flow of hot coolant into the cabin area where it is used to heat the interior. At some point they will fail - generally anytime 10-15 years, but sooner if they are neglected, by not having the coolant flushed and replaced as per the vehicle schedule. Without a properly functioning matrix, you will be relying on the cabin heating resistors for warmth, which can only provide limited warmth as they are only use to to provide demisting or help with increasing the cabin temperature until the engine has warmed up.

This is only a possible issue, so does need some investigation.

[citroenguy]

Do you have a Webasto diesel heater?
Pretty sure they were standard equipment on 2.0HDI and up until euro 6.
At least in colder countries.
Or electric "toaster"/PTC heater might be broken

[ExOduS442xb]

What can happen is the heater matrix can become blocked up, which restricts the flow of hot coolant into the cabin area where it is used to heat the interior. At some point they will fail - generally anytime 10-15 years, but sooner if they are neglected, by not having the coolant flushed and replaced as per the vehicle schedule. Without a properly functioning matrix, you will be relying on the cabin heating resistors for warmth, which can only provide limited warmth as they are only use to to provide demisting or help with increasing the cabin temperature until the engine has warmed up.

This is only a possible issue, so does need some investigation.

Would you suggest buying new heater matrix or trying to "fix" the one I currently have? I am not sure how can it be repaired, by flushing? I am more open for buying the new one and then changing the coolant as well, the prices are starting from 45 euros and going up to almost 300 euro. Some brand names like Mahle and Nissens are around 70-100 euro depending where you buy it, those around 45 euro are probably from China (VAN WEZEL).

Do you have a Webasto diesel heater?
Pretty sure they were standard equipment on 2.0HDI and up until euro 6.
At least in colder countries.
Or electric "toaster"/PTC heater might be broken

Actually not, I don't have Webasto. The car is an 3.0 HDi, it's EURO 5 model.
I live in eastern part Croatia, it can get quite cold, but climate is changing and for the past few years it rarely went below -20, mostly 0 and -5, but the car is parked within the house garage and it's mostly around 10' there.

Since I have no other issues it could most likely be heater matrix. Is there any way I could test this, I am guessing Diagbox or Lexia can't do anything? Because to get it out I need to disassemble half of the car.

[citroenguy]

Never seen a PSA car with blocked heater matrix, but i guess it can.
More common with PTC heater fault or burned contacts.

[citroenguy]

This thing:

[GiveMeABreak]

But that heater resistance only provides basic heating until the engine warms up for cold mornings or to help with defrosting. If 'ExOduS442xb' is saying that the cabin temperature does not heat up very much even when the engine at operating temperature, then there is another issue.

@ExOduS442xb: I wouldn't spend any money yet until you have had it checked out, otherwise you could be wasting money.

[Ross_K]

This thing:

That's not it surely, in front of the pollen filter, with the pipes going in? That'd be too accessible for a Citroen

[citroenguy]

No i think it's after the pollen filter, further back toward the center console.
The 4 wire thing in front is the fan speed regulator "resistor pack"

[CitroJim]

I have no experience on this particular car or its heater but a common problem on the superficially similar Pug 407 was broken air control flaps in the heater box...

I don't know if this is a common or known problem on the X7 too but thought it was worth mentioning as flaps that no longer move could cause the issue here...

[Ross_K]

If I understand correctly the silver pipes go into the heater matrix (which is seen in the photo above), and based on this post of Marc's the electric heater pack is above the pipes (item 2 in the picture below, and out of view in the photo above):

Disconnect the connector (Heater element) .
Unclip the connector (Heater element) at "a".

Remove:

• The earth bolt (3)
• The (1) bolt

Remove the passenger compartment air heating resistor (2).

Refit:

• The cabin air heating element (2)
• The (1) bolt
• The earth bolt (3)

Refasten the connector (Heater element) as "a".
Reconnect the connector (Heater element).

And my understanding that the silver item is the heater matrix is based on a random eBay ad...? Correct me if I'm wrong as I'm more used to seeing heater matrixes buried deep inside the dash of Citroens

I have no experience on this particular car or its heater but a common problem on the superficially similar Pug 407 was broken air control flaps in the heater box...

I don't know if this is a common or known problem on the X7 too but thought it was worth mentioning as flaps that no longer move could cause the issue here...

If I remember correctly you can "exercise" the flaps in Lexia or Diagbox