heater problem

[James T]

I have a 306 (N). But the heaters don't seem to be working properly. The de-mister doesn't blow hot air at all, only cold and the blowers into the car only blow slightly warm. I have changed the thermostat as it was stuck open and completeley flushed out the entire system, refilled and bled. Any ideas what the problem could be? Any thoughts would be greatly recieved.

 

[davek]

I have a 306 (N). But the heaters don't seem to be working properly. The de-mister doesn't blow hot air at all, only cold and the blowers into the car only blow slightly warm. I have changed the thermostat as it was stuck open and completeley flushed out the entire system, refilled and bled. Any ideas what the problem could be? Any thoughts would be greatly recieved.

Possibly air lock in system. If not, the heater matrix might be blocked with gunge or the ventilator baffles not operating properly. I'd try to dislodge the air bubble-it's the cheapest option.
Davek

 

[Adrian Sims]

Possibly air lock in system. If not, the heater matrix might be blocked with gunge or the ventilator baffles not operating properly. I'd try to dislodge the air bubble-it's the cheapest option.
Davek

Hi there,

Sorry to hijack the thread but I have recently had the same problem (again on a 306 N reg)

I also changed the thermostat and found that it was faulty.

How do you bleed the system to remove air locks, any defined procedure?

Many thanks

Adrian

 

[davek]

How do you bleed the system to remove air locks, any defined procedure?

Many thanks

Garages have a pressure vessel which they attach to the reservoir filler neck and force coolant right through the system. The secret is to have a supply of coolant at a higher level than the highest point in the system. A big plastic bottle held up high and supplying coolant via a piece of hosepipe tightly fitted into the top hose of the system can do the job. My old Renault 21 had little hand operated valves in the top hose and heater hose which ensured all the air was out. In a troublesome case you might try removing the pressure cap and allowing the engine to run till it's so hot the fans cut in and the coolant boils out of the reservoir.Might bring the air bubble out with it. Daft innit,- in the search for efficiency bonnet heights get lower and lower and you can't have a big tall radiator anymore, which didn't create these problems.
DaveK.

 

[Nik Andy]

I believe the correct procedure is to get an old empty coke bottle and cut the bottom off it, then stick it upside down (filler neck first) into the coolant vessel and fill the coke bottle up, this gives enough of a header to fill the system completely. I read about this problem and fix in car mechanics magazine several years ago, cant remember if they used anything the seal the bottle though.

You could write to them though?
http://www.carmechanicsmag.co.uk/

Andy

 

[Dave English]

I believe the correct procedure is to get an old empty coke bottle and cut the bottom off it, then stick it upside down (filler neck first) into the coolant vessel and fill the coke bottle up, this gives enough of a header to fill the system completely. I read about this problem and fix in car mechanics magazine several years ago

It is in the HBOL too!

, cant remember if they used anything the seal the bottle though.

They make a good enough fit as is.

The it is just a matter of loosening the bleed screw(s) till coolant flows, closing them, running the engine up to temp, massaging the fat hoses & repeating ad nauseam (well until no more air from bleeds)

What could be easier :-^)

 

[Neil D]

HI James, I hate to be the bearer of bad news, but I had exactly the same symptoms on my 306 (sold now) last year, with the air being cold on the screen and luke warm on the vents (centre ones, not so much on the side ones). I turned out to be my heater matrix leaking slightly. I lost no water and water going in an out by the bulkhead were boiling. I had to have to matrix changed. The labour is the expensive bit here, the part costs about £50, but the labour for me was £250. The problem being the dash has to come out. If you feel really competant and have a couple of free days over Christmas, you could maybe give it a go yourself. I didn't because I was afraid to take the airbag off, but I've taken it off since and it's no problem. Haynes manual covers the lot,

Hope it helps, and sorry to dissappoint,

Neil

 

[wolves]

had similar problem with my 405 diesel,after several trips to garage to have the system bled,and stat changed which made no difference.was told to check the flaps were opening fully, and to check for a blocked matrix.flaps could be heard to be opening and closing so went for the matrix option.before going to garage i took the dash off and replaced it when the car came back saved them time and me money,verdict A BLOCKED MATRIX cost about £40.inside temp now about 55*c.