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Hi guys! Newbie here! Just bought a 2008 308. Problem is the heater not hot. Now, thermostat been changed, matrix flushed.

It does go cold when turned to position, just hot ain't hot! I'm suspecting electrical. Any ideas?
 

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mmmmm.... I did but maybe not properly. Had an old Bmw that was a pia to bleed. Any tricks or a link to a how to?

Any possibility symptoms could be electrical if not his?

Thanks for your help.
 

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Have you flushed and replaced coolant recently?

First get the engine warm but not hot! Carefully remove the expansion cap, then remove the bleeder cap,(try not to drop it) replace bleeder cap when all air has passed and coolant starts flowing out, check level and replace expansion cap!

Take the car for a short spin try the heating again then repeat until no air is in the system - if that fails, then get it scanned!
 

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Hi guys! Newbie here! Just bought a 2008 308. Problem is the heater not hot. Now, thermostat been changed, matrix flushed.

It does go cold when turned to position, just hot ain't hot! I'm suspecting electrical. Any ideas?
Hi ya. Did you ever solve this. I've got same problem mine!

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I had the same problem. Turned out to be the heater matrix. The car ran fine at 90 once warm.

I took the panel in the passenger footwell off that covers the inlet and outlet pipes. Ran the engine until hot. At this stage both pipes were very hot. Switched fan to 4 and found that the air was hot for less than a minute. The outlet pipe was much cooler by this time. I reckoned this meant a lack of flow - blockage somewhere or waterpump. I didn't think it could be the thermostat as the heater is still in the flow circuit when it's closed.

Anyway I went for the cheapest option of a matrix off ebay for £30. Worked a treat. I could barely blow through the old matrix. A flush would not have got rid of the muck in there. I hope the rest of the system isn't similarly choked up. The drained coolant looked clean enough.

By the way the O rings don't seem to be available from Peugeot on their own. They are 16mm Id with 3.5mm cross section. Ebay again.

Sorry about length of this post but it'll be worth it when your heater starts working again.
 

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Thanks nico. Did it take long to change and is it easy to get to? You imagine removing the whole dash!

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Actually easier than I thought. Dashboard doesn't have to come out. Once I got the panel in the passenger footwell off I removed the bracket that holds the 2 pipes to the bulkhead (2 small screws - quite difficult to see). That gave enough movement to move the pipes out of the way when disconnected from the matrix (clipped in). There are then 4 screws that hold the matrix into the housing.

Obviously the system has to be drained but that still leaves coolant in the heater pipes and matrix. I put plastic sheet under the unit and it covered the whole (so I thought) footwell too so I could lift out the coolant. I still managed to spill a half litre or so - it comes out fast!

It took barely an hour to do in the drive. It took me longer to dry the carpets out!

Haynes manual has it all and is reasonably detailed. You may find something on youtube about it. The matrix is the same as some Citroen C3 Picassos (09 - 15). Definately use new O rings and clean the area where the O rings sit on the pipes.

Hope it goes well if you decide to go ahead.
 

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Have you flushed and replaced coolant recently?

First get the engine warm but not hot! Carefully remove the expansion cap, then remove the bleeder cap,(try not to drop it) replace bleeder cap when all air has passed and coolant starts flowing out, check level and replace expansion cap!

Take the car for a short spin try the heating again then repeat until no air is in the system - if that fails, then get it scanned!
am going to try this for mine,where is the bleeder cap though, i've seen pictures of several..is there one by the bulkhead near the heater pipes ? thanks. ps 2010 308 1.6.
 

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not sure I have an air blockage after all. What has caught my attention though is that while warming the engine up the top return hose to the radiator was quite warm even though the temp gauge in the car hadn't reached it's normal 90c. Also the coolant in the header tank was warm too. I'm not sure at what stage the thermostat is due to start opening tbh but if it's around 90c then maybe I have a faulty thermostat ?

One other question on the opp side of the radiator are another inlet and outlet from the radiator side that seem to go down into 'something' at the back of the alternator then out again up to an aluminium cylinder with a valve on top - this then disappears in it's aluminium pipes towards the bulkhead. Any ideas ?
 

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I assume your heaters are not blowing hot air? Have you had the heaters on full and run the engine for over 20 mins or more and still blows warm/cold?

If it is the thermostat it's easy/cheap to check or replace - I'm sure thermostat opens around 90'c so coolant will be extremely hot!

Regards to other question, not sure if you're on about your air-con unit or the water pump but a failing water pump will not help.
 

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I'm sure thermostat is good. Up to 90 degree in about 3 miles and then stays there all journey. Metal Heater pipes entering heater are too hot to touch. On low fan speed heater is warm but on 3 or above barely Luke warm.my wife's 206cc hot after 1 mile.

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I'm sure thermostat is good. Up to 90 degree in about 3 miles and then stays there all journey. Metal Heater pipes entering heater are too hot to touch. On low fan speed heater is warm but on 3 or above barely Luke warm.my wife's 206cc hot after 1 mile.

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Mines pretty much the same, on low blower the heat is hot..although not as hot as it has been..when the blower is turned up the air is colder, certainly not what I would call warm even. I took out and cleaned the pollen filter, which was new in April, and gave it a good clean out but it hasn't affected the heat but will affect the volume of air the blower pushes through.. I also topped up the header tank which was only on low, now it's just below the high mark. Am going to test it again today and check at what temp the thermostat is opening..when it's stopped raining.
 

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It may just be air in the system which will need to be bled out, or system could do with a flush, if it's not been done for a while, fill with fresh coolant and then bleed system as shown on video but check thermostat too, to rule that out!
 

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308 Peugeot - Heater not working

Have been following the forum to see if I could find out why my 308 heater isn't working. Have found absolutely nothing of any use. I've just fixed mine and I'll explain my process below:

First I thought it was the thermostat - but because the heater flow bypasses the thermostat - clearly it wasn't that.

Then I checked the heater matrix by disconnecting the hoses at the thermostat housing and put the hose in one end and it flowed out the other - so clearly not that either.

The comes the refilling and the bleeding - you just simply can't do that without the bottle that goes on top of the expansion tank. Rather than but the Peugeot tool - I went to the wreckers and bought an old pressure cap. Then put it in the drill press and drilled the guts out of it - then cut the bottom off an old drink bottle and inverted it with the crew top fitting nicely in the hole I had drilled. Then araldite all round to seal it - check to confirm it seals before using.

Next - install the flash new tool you have made - fill it with antifreeze/coolant and watch it bubble down into the engine then keep topping up the new bottle until it the level stops dropping.

Then - find the bleed screw cap where the heater hose connects through the bulkhead behind the engine - I took the induction hose off to do that.

Open the bleed cap - then close it when the flow has started. When you do this you will notice bubbles coming up through the water in your new bottle/tool. When the bubbles stop - open the cap again and let water flow. Keep doing this until no bubbles come up when you do it - you need to do this patiently and slowly and wait a minute or two in between. Don't let the bottle empty while doing this - keep it full

After the bubbles stop - locate the bleed screw on the thermostat housing - you can see it if you look down behind the wiring harness holder - perhaps slide that up and out of the way - open the belled screw and let water flow out of it.

I found that air can get trapped in the top hose where it bends - so I pushed it down so the air would flow back up towards the thermostat - this produced a lot of bubbles at the bottle tool - I did this a few times and kept squeezing the hose while doing it. finally there were no more bubbles and the water level went up and down when I squeezed it.

Then AFTER doing all of this - I topped up the bottle again and started the engine and let it run at around 2,000rpm to warm up - at first there were bubbles but they gradually decreased and stopped.

After a nice long run and a few stops and starts at the shops along the way - the heater is working perfectly.

I hope this helps someone with their problem. And to those recommending replacing the heater core PLEASE don't recommend to anyone that their heater matrix is blocked when both the hoses are hot!!
 
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