No hot air

[phil7865]

Had my jag (2001 s type 3ltr) a few months now and needed the heating on a few days ago, so i set the temp to high and waited for the hot air. some miles later still cold.

Any guidance would be great.

[Jaguar Owners Club]

Hi Phillip

 

It sounds like you could have air in the cooling system. Generally this does not naturally occur but if you have a small coolant leak somewhere in the system or if there has been any work carried out on the cooling system then this could have introduced some air into the heater. The way to determine this is to feel the heater hoses and if they are hot and then further along there is a cold area then that's where the air is (which blocks the flow of coolant). The solution then is to purge the air by letting it out through a bleed point or temporarily loosening a hose clip to enable the air to escape.

Alternatively, It could be the hot/cold air heater distribution flap or motor stuck in the cold position. Possibly cycling the hot/cold heater control backwards and forwards may assist in getting it operational again.

 

Hope this helps?  Please keep us updated on this fault as it may affect other members who are now switching their heating onto the hot setting.

 

Regards,     Trevor

[phil7865]

Could anybody confirm that the bleed valve is built into the plastic section of the top coolant hose.I don't want to go forcing things open when they are not ment to be opened.

Thanks.

[Jaguar Owners Club]

It would be on the top hose and the cap looks the same as a tyre valve dust cap.

It is worthwhile opening it very gently and beware of steam & boiling hot water being emitted under high pressure!

If you have got air in the system, then you may have to investigate further as to how it got in there?

[phil7865]

I replaced the top hose a few days ago due to leakage trom the plastic section.

The valve you described isn't on the top hose but attatched to a narrow aluminium pipe, one end travells along the " V " section of the engine towards the bulkhead and the other end travells along the inner near side wing and down towards the bulk head. There is however what looks like a valve on the plastic section of the top hose, it has a slotted section in the middle probably for a screwdriver and in very small lettering says "service only"  and is positioned directly below the large pipe from the air filter.

[Jaguar Owners Club]

Found this description for bleeding the system.

The valve would be on the plastic section of the top hose.

The other (aluminium) pipe that you describe sounds like an air conditioning pipe.

 

The bleed valve is on a pipe just to the lower right of the throttle body at the front of the engine. To open it, turn it a 1/4 turn clockwise. This allows air / water to run down a pipe at the back of it, back to the expansion tank.
With the valve, open re-fill the system until water starts to come back to the tank via the pipe off the back of the bleed. Once that's done, start the car and run it with the heater on 29 degrees for 5 mins, topping up the tank as necessary.
Once the water level is constant, close the valve and put the lid back on.

[phil7865]

I've just bled the system as suggested and made no difference.Should i know disconnect the heater control valve.

I've read that if its disconnecter it should pump out hot air.

[Jaguar Owners Club]

You could try that but be cautious of hot steam/water suddenly being emitted under high pressure!

Also, make sure that the heater control is in the 'hot' position before bleeding the system

[phil7865]

Sorry i ment disconnect the control valve electricaly by pulling the multi connector off, which will put the pump into hot setting.(if what i read is correct).

Whot do rou think.

[Jaguar Owners Club]

sorry...misunderstood your message.

Yes, that is what I have read also.

Give it a try and see if the hoses are getting hot whilst you are running the heating system.

[phil7865]

After running the car with the heater control valve disconnected electrically there is still no heat, so i'm assuming that the valve is stuck shut. Is this a part that i can clean up and get working or would it be better to replace.

Any thoughts please.

[Jaguar Owners Club]

I would imagine if it is stuck with corrosion then replacement is the best method.

I have found there are quite a few on eBay at the moment...quite reasonably priced!

 

http://www.ebay.co.uk/sch/i.html?_trksid=p2050601.m570.l1313.TR1.TRC0.A0.Xjaguar+s+type+heater+valve&_nkw=jaguar+s+type+heater+valve&_sacat=0&_from=R40

[George]

Hi, I have the same problem with my 2006 X Type 3Ltr,  I will try to find a the bleed valve to see if there is air in the system.  But today after driving for 15 mins with cold air blowing on me I stopped the engine for a minute and when turned back on there was instant heat, so I think it is more of a valve sticking.  Do you know if the S type valve is the same as for the X type? I cant see any X type valves on eBay.

 

George

[phil7865]

I'm unsure if the engines are exactly the same. If thay are then the bleed valve is built into the top radiator hose on the hard plastic section, it has a screwdriver slot in it.But the 3ltr  X-type may only share the same block and head averything else may be configured differently.Your best bet is to post a thread on the X-type forum.

Sorry i can't help any further.

[phil7865]

I have now fitted a new OE heater control valve and hot air is now flowing through the vents.....superb.

It was a pig of a job due to poor access but well worth it.

[pjt247]

I have the same problem with my 2001 S-type. I've put a new heater control valve in but the blower still blows cold air. What else can I try?

[O.T.H]

Hi --I may be wrong but to me, it sounds as though you have an  air lock in the system  somewhere ????

[Jim Elston]

It may be the outside temperature sensor. Mine was doing the same the same as it thought that the outside temp wass 38 degrees. A cheap and easy fix! The sensor is located under the front bumper and are cheap on E-bay.

Try turning the A/C off and out the temp to maximum (hi) If all is well there, worth checking you have coolant in the system...