Lack of Heat on Xantia 1.9TD Mk2

Gregg1100 · Post by **Gregg1100** » 03 Sep 2009, 00:11

Hi,
If the heater hoses from matrix ( felt from engine compartment ) are hot at both sides, are there other things that can be wrong.?
The heater control sllder doesn't seem to do much, nor does the recirculating/ fresh air control. I had to do the gearwheel drop down job on the cabin to demister cable a while ago. I seem to remember something about a sensor that is tucked away behind one of the centre air outlets, but not sure. Can't see too much with all the junk in the way behind radio/cd.
Thanks,
Greg

jgra1 · Post by **jgra1** » 03 Sep 2009, 00:32

hi Gregg, I think both hoses being hot can still confirm a blocked matrix and therefore no hot air

Malolm pointed this out to me (citronut)

John

Post by **CitroJim** » 03 Sep 2009, 06:29

It could be the matrix but I'd be wondering firstly if the motor-driven flap over the matrix face, which regulates the volume of hot air coming out of the matrix, is working OK. The motor or its gear train does sometimes fail.

Problems with sensors are rare and will usually result in the heater putting out some hot air initially and then going cold. A Lexia session will prove sensors and the operation of the ECU and motor-driven flap.

Xantidote · Post by **Xantidote** » 03 Sep 2009, 12:08

Jim,

The "motor driven flap". Does Greg's Xantia have this by virtue of being a Mk 2, or because it's got air-con?

Makes me grateful for the simplicity of my Mk 1, but I ask because I'm sure in due course I'll end up with a Mk 2, and have to accept all the added technology & electric issues that will bring. I like my Mk 1 because it's so basic (by present standards)

Martin

Clogzz · Post by **Clogzz** » 03 Sep 2009, 13:20

Because it’s got aircon, called ‘climate control’ in that it regulates the temperature by adjusting the motorised heater flap.
The flap motor is visible at the very bottom front of the centre console on the passenger’s side.

Gregg1100 · Post by **Gregg1100** » 15 Nov 2009, 19:24

Hi,
Is there anything I can do with that little motor in dash. The air intake and re-cirulatory sliders don't do anything either. I managed to get some heat to direct to screen by refitting the cog after it had slipped out of mesh ( direction cable- floor to screen range ).
There is some heat coming from heater, but there again, it is not yet cold.. When it does start to get cold, it will be back to having the windows open to defrost the glass. The temperature gauge reads under 75 deg when hot ( 15 mile journey to work---A roads, dual carriage way and a little blast up M4.? What do other temperatures gauges read in this forum.?
I have had strict orders from SWMBO to get some heat in the car .

Greg

Post by **CitroJim** » 15 Nov 2009, 20:19

That sounds like the engine is running a bit cool Greg. On a MK2 the mid-way on the gauge is 90 degrees I believe so the normal running temperature should be near that.

The thermostat may be duff and there again it may be the wrong type. Some engines have a thermostat with a "top hat" on it to open the bypass passage which includes the heater circuit. If the wrong type is fitted than the passage might fail to open properly and will starve the matrix of hot water.

I know it is not easy in a TD but can you feel lots of heat in the pipes going to the matrix? They should be well warm even before the thermostat opens as the matrix forms part of the bypass circuit.

Don't there's a bleed valve on the matrix elbow. It's worth trying a bleed there and also checking the little bypass pipe that runs from the front LH side of the head is clear. The alloy spigot that the pipe slips over is very small bore and can block up. This little pipe is pretty critical.

1.9TDs normally have brilliant heaters.

Gregg1100 · Post by **Gregg1100** » 15 Nov 2009, 23:14

Hi Jim,
Thanks for that. I have to put more antifreeze in the car, so I will whip out the thermostat and have a look at which one is in there. That little outlet- is that the one behind the injection pump ?. Or are you looking at it from the rear as in the BOL. They say the thermostat housing for instance is on the left hand side of engine. Not on any 1.9 TD I have seen lol. Anyway, I know what you are on about, and I will look first thing tomorrow. Bloody rain most of next week, so it is a car job to work, and not the bike. Nowhere to keep wet clobber, except on bunk in the cab. Not recommended if on a night out.
Thanks,
Greg

mark21td · Post by **mark21td** » 16 Nov 2009, 10:30

CitroJim wrote:
Problems with sensors are rare and will usually result in the heater putting out some hot air initially and then going cold. A Lexia session will prove sensors and the operation of the ECU and motor-driven flap.

Thats what mine's doing, gets hot and then cold, and the blower seams slow in auto.

Xantidote · Post by **Xantidote** » 16 Nov 2009, 11:30

Temperature gauges are not necessarily accurate. Has it always read 75?

My original thermostat lasted 13 years, and the gauge's needle always sat in the middle of the white 80 mark. When it failed, the needle sat (IIRC) between 70-75. With the new thermostat, the needle sits on the bottom edge of the gauge's 80 mark. Even with the faulty thermostat, it gave out enough heat into the car to see me through last winter, though I always felt it could be hotter. As an aside, as soon as I fitted the new thermostat, I noticed the engine seemed to run more smoothly during warm-up.

Cheers - Martin

citronut · Post by **citronut** » 16 Nov 2009, 13:46

is there plenty of blow comming out of the vents with the fan on full speed,

if not your pollen/cabin filter could be blocked,

regards malcolm

Gregg1100 · Post by **Gregg1100** » 28 Nov 2009, 02:34

Hi,
Should be able to look at car this weekend. I will pick up a new thermostat and check the pollen filter as well.
How can I check that the water valve is fully open- or is it something to do with electrics again? . What was wrong with a cable?.
Greg

DickieG · Post by **DickieG** » 28 Nov 2009, 07:04

Gregg1100 wrote:How can I check that the water valve is fully open- or is it something to do with electrics again?

That's easy to check because there isn't a water valve on a Xantia

Post by **CitroJim** » 28 Nov 2009, 08:45

Just feel the hoses when the engine is good and hot Greg and both should be nice and toasty to the touch!

I always think it's a good thing there is no water valve on the matrix. One less thing to fail!

Gregg1100 · Post by **Gregg1100** » 28 Nov 2009, 15:49

Hi Jim,
At least with a water valve one can fully shut or open the flow of hot water through the system.
The temperature slider doesn't seem to do much on this car, didn't do nothing at all on my old L-reg TD ( no aircon ).

What is the temperature slider connected to to raise or lower the amount of heat available then, please. If it is something to do with a part fitted in the vent on the dash, what can I do to sort it out ?
The heater hoses either side of the matrix are hot. A new radiator is fitted to the car.
Still haven't got thermostat,- wife not well now, so will have to leave it for another week. The shifts I do are just work to bed at the moment.
Thanks,
Greg

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