aircon+heater problem

[depeche101]

Hi guys,
As I'm new to here I'll first introduce myself and my car.
My name is Martin and I'm in Tallinn, Estonia.
The car I'm driving is a 2001 406 SW 2,0 ST. Automatic gearbox, Climate control, Heated seats, cruise control, rain sensor and electric windows+mirrors.
Now to the problem I'm having:
As the weather went colder (around -5 - +5 here now) I noticed the lack of heat in my car.
The situation is that the heater blows warm air only from dashboard to my face. Onto the windscreen and to the legs only cold air comes. No matter if I put 22, 25 or 30 on my climate control the air to the window and legs is still cold. At least colder than it should be. It might be around 15 degrees or so but it's cold especially if you're driving longer way on motorway..
At the same time if I'm in a warm garage and select 14 degrees the aircon starts to blow cold air and that comes to all the vents..so the problem is only with heat.
I've checked the internal temperature sensor - fan worked fine, I've changed the oputside temp sensor in the mirror - still nothing. Yesterday I was at my local Peugeot dealer - they put the computer on and said that it shows no faults with the climate control..They tried to look at the motors which move the flaps behind the dash and said that the one that selects where the air is being blowed works fine (that one I already knew:)) and also the other ones that selects between cold and warm air seem to work. Seems only because they couldn't take it off and said that if they touch the motor they can feel that it works...Their best guess now is that the fault most likely is that the motor itself might be ok but the connection from the motor to the flap might be broken or smthng so that even as it moves (remember it blows cold air from the aircon) it won't move enough...to check that they need to remove the dash...so totally they're telling me that I should leave the car to their workshop for most likely more than one day which really isn't an option to me... (Let's not speak of the cost of one full days work at their workshop). And of course it's just their guess now..they don't know for sure. So before I agree to give the car to them for at least 2 days I was hoping to get some information from you guys...anyone had this kind of a problem? Any hints on what to do, where to check? As the winter is coming I want to get the heating to work...no fun in driving in cold car when it's -15 or more outside:(
So...it became a long story but perhaps someone has an idea..

martin with cold 406

[Welly]

Hello there,

One of our members called miniman has the same problem as you with no heat, try to PM him and ask if he has found out what was wrong.

He thought at first that it was the Hot water control valve that was faulty and this is located behind the dash and lets hot water into the heater matrix.

It is strange how the air direction works on cooling but not heating, this could be a communication fault of the climate controller itself?

And, I hope you don't mind me saying but Tallinn, WOW, what a place to live? I only know of all the Bars/Girls etc. as a popular place for parties, but must be an interesting place to be all year round

[depeche101]

Hi Welton,

Thanks for the answer.
I looked at miniman's post but I think that these are different things. miniman's climate blowed either ot hor cold an nothing between...mine again blows the correct temperature from the dash...but not to the legs and window...
To make things even stranger...If the car is in a warm garage and engine running..after abt 5-10 minutes surprise-surprise...war air starts to come to legs and windscreen...of course that air will turn to cold as I drive outside....It'll be warm only for abt 10-15 minutes...then it'll start blowing cold again to the feet...still from the dash hot air comes... total mystery...
Local peugeot dealer said the checked the electronics with the computer and got no error message.
As far as living in Tallinn:) it is a great place to be and I know that it's a popular place for British bachelor parties and trust me..I've noticed that: Specially on summer time the old towns bars and pubs are full on quite drunk brits
martin

[Welly]

When you say that the heater starts to work better if you leave the car running for a while in the garage it makes me think of 2 things:

The pipework to the heater needs venting (try the 'tyre valve' looking air vent on the hose just before it goes into the bulkhead in the engine bay) be careful not to remove it completely because if you drop it you can loose it (not good).

I find it's best to do this with the engine running, crack open the valve cap a little and if water runs out then it is ok, if nothing happens then you need to top up BUT you have to make a 'Heath Robinson' bottle to fit in the neck of the expansion bottle to enable you to over-fill the system so you can vent it properly (sounds hard but quite simple in reality).

The second thing is that the Thermostat in the system may be stuck open resulting in longer warm up times when driving along for the engine but increased heat build up when stationary allowing the heater to work better.

The Peugeots climate control will not let any air flow to the vents until the water is up to about 70 degC (this will take ages if you have an airlock or stuck thermostat.

My Mitsubishi I had recently would NOT allow air to blow onto your feet UNTIL the water was warm enough, maybe the Peugeot has something similar, I do notice an increase in fan speed once the engine temp is over 70 deg. which allows full heating to take place.

After saying all this though, I suppose it is possible that the connections which work all the dampers to change the air direction could be faulty, but finding the exact problem could be a nightmare, usually the climate system is pretty reliable on the Pug, it's not really a common problem.

And as for Drunken Brits......That's really all we are good at, letting ourselves and our Country down when travelling abroad

[depeche101]

Hi Welton,

The thermostat crossed my mind also...although the Peugeot dealers said that it worked...
I'll try to vent the system...I did look at the expansion bottle and it seemed to have enough antifreeze in it...but I'll check it when I'll get home.
I also read from some Forum that Peugeot keeps blowing hot air from the dash to the side windows in order to prevent misting them up...but it is strange how warm air comes to some places and not to other..but perhaps it has some kind of feature like your Mitsubishi had..
Anyway..I'll try to vent the pipes and I'll cover the radiator..if the thermostat is not working covering the radiator might help..if I'll get more warm air then then I'll know that it's the thermostat. I'll let you know the outcome
As for the brits..luckily I don't go to Old Town (medieval part of Tallin which is the town centre where most of the bars and pubs are) much..work, school and 2 kids take most of my time (and now my 406:)) But as long as they are peaceful I don't mind..after all...spending all their money here they are good to some part of our economy
But if the football fans come to Tallinn I won't put my nose out of my house:)
Martin

[mjb]

The other day I discovered the coolant can be bled without the aid of a makeshift header tank by parking the car on a slight angle (ie. with the right-hand side wheels on the kerb). And I can also vouch for the being very careful with the cap!!!


I think the thing with the dash vents blowing warm air is a bit of a red herring, probably just picking up heat from miscellaneous stuff behind the dash. Unless I'm mistaken, the air should be HOT not warm...

If you get to the bottom of it please let us know, I'd kill for heating that warms the car up in under 50 miles!

[jameslxdt]

He thought at first that it was the Hot water control valve that was faulty and this is located behind the dash and lets hot water into the heater matrix.

Welton

the hot water control valve idea was never used by peugeot, it was a ford idea, hence its crap,

peugeot use a flap which diverts air coming from the pollen filter away from the heater matrix, this is frequently known for getting stuck though

the recirc flaps also often get stuck, could be a thermostat
have come across a few with defective sunshine sensors, but only the d8's

as this is a d9 it could be a climate control module fault or the bsi maybe at fault

[Welly]

He thought at first that it was the Hot water control valve that was faulty and this is located behind the dash and lets hot water into the heater matrix.

Welton

the hot water control valve idea was never used by peugeot, it was a ford idea, hence its crap,

peugeot use a flap which diverts air coming from the pollen filter away from the heater matrix, this is frequently known for getting stuck though

I didn't know that, I can hear a sort of whistling when the cabin temp is almost at it's set point and always assumed it was a control valve throttling down, I suppose then it is air pressure escaping past the 'flap' until it's fully closed.

Cheers for the info.

depeche101:

I don't know if you've tried this but I was looking at the way mine works last night. The face vents are always on in ANY position you choose windscreen or feet, for example. You have to close the face vents down with the on/off wheel thing to direct more air to the feet.

[depeche101]

Hi guys,
Covered up the radiator, but I managed only to do it today so I'll have to wait for tomorrow morning to see the results...
Welton, I know the face vents are always on...that's not the problem...even if I close them of course I'll get more air to feet but the air is cold:( That's the problem...still...I'm having the feeling that it's either the thermostat (which seems unlikely cause the engine temp comes to 90 as it used to be..so quite fast) or the flaps that allows the heat from matrix...Anyone have any ideas how to get to that flap? Remove the dash?:(
So...still trying and air still cold.

dep

[jameslxdt]

unfortunatley you do have to remove the complete dash and its a real nightmare to do, can take about 8 hours and your arms get cut to bits

[depeche101]

Well-well
Finally the car is warm again:)
Simple problem - heater matrix was somewhat stuck. Not totally but enough to be warm only on the upper side. Changed that and voila - everything fine again.
Thank's everybody for answering and sharing ideas.

Rgrds
Dep