interior heater isnt getting hot

turbulence23 · Post by **turbulence23** » October 11th, 2007, 6:43 pm

got a problem but can''t find a good answer..

its getting a little bit colder now so last week i turned on the car heating... after driving for a while the air flowing out doesnt feel warm, its getting a little bit warm but not as warm as it supposed to be..

thought of air in the coolant but temperature reeding looks fine, there isnt any air in the system that i checked..
could the heating unit be broken? and so what could be broken? do i need a new heater unit??? or are there other things to check first

checked the manual, looks like hot coolant flows through the heater unit and this heats up the air or is there another system working that might be broken??

really need to know, also have sometimes foggy windows so good heating is critical then or else i don't see nothing

PS: do i really need do dismantle the dash to get to the heaterunit?

shameem · Post by **shameem** » October 11th, 2007, 10:55 pm

There are many possible faults - few are

- You might have a faulty engine thermostat that is stuck open
- Blockage in the heater core

Smith18 · Post by **Smith18** » October 12th, 2007, 4:06 am

Check coolant level also, on mine i had a leaky radiator and it would be low on coolant and it wouldn't flow right until i revved it up.

solo_ryder · Post by **solo_ryder** » October 12th, 2007, 8:54 am

Smith18 wrote:Check coolant level also, on mine i had a leaky radiator and it would be low on coolant and it wouldn't flow right until i revved it up.

Happened to me before I swapped the motor, the seal on the waterpump went bad and then the heater would not work right, check coolant levels first.

SuperK · Post by **SuperK** » October 12th, 2007, 9:49 am

My thermostat was stuck open and it wouldn't heat.

replaced the thermo and it burns wonderfully. I'd check that first if I were you.

SuperK · Post by **SuperK** » October 12th, 2007, 9:49 am

My thermostat was stuck open and it wouldn't heat.

replaced the thermo and it burns wonderfully. I'd check that first if I were you.

SuperK · Post by **SuperK** » October 12th, 2007, 9:51 am

My thermostat was stuck open and it wouldn't heat.

replaced the thermo and it burns wonderfully. I'd check that first if I were you.

Nd4SpdSe · Post by **Nd4SpdSe** » October 12th, 2007, 11:58 am

Diddo. Definitely a worthwhile check if your coolant level is good. One thing i did notice, mind you it was in the winter, is that the engine temperature took alot longer to get to normal than it used to as well, but even when i got there, it still didn't blast out nice hot air.

Most will fail open, there are even thermostates that are called "fail-safe" in which they are designed to go open when they fail.

turbulence23 · Post by **turbulence23** » October 22nd, 2007, 5:01 pm

thanx for the replys...

so checking up the thermostat is a must... coolant level is good, just checked i a little time back, no air in the system no leakage..

also think the heatercore might be failing as i have a lot of problems with condensation on the inside of the windscreen....

might be leaking or something, or could anything else cause the interieur window to fog up that much??

Nd4SpdSe · Post by **Nd4SpdSe** » October 22nd, 2007, 5:24 pm

The fogging up is a common problem it seems, I know my mx-3 did it in the winter and so did the 626. What solved the problem for me is to set air to "Fresh" rather than "Recirculate", once I did thatI never had a problem with fogging in the Mx-3 since...

Tunes67 · Post by **Tunes67** » October 22nd, 2007, 5:26 pm

One other thing that hasnt been mentioned yet is the waterpump itself. If the water pump impeller has corroded away to nothing.. it could also prevent coolant/water from circulating to the heater core properly. Though I have seen one on a 4 cyl engine that still kept circulating the coolant even after the impeller was long toast.

You dont have to remove the heater core to check it for blockages. Simply disconnect both heater core hoses from the engine.. connect a garden hose to one heater core hose and another hose leading to a bucket (or other wise out of the engine bay) Then turn on the water.. do this slowly and gradually.. then just see if water flows through the heater core. If not.. its blocked and needs to be replaced.

If water does flow through the heater core then look at the possibility of a stuck open thermostat or waterpump failure.

Tunes67

turbulence23 · Post by **turbulence23** » October 22nd, 2007, 5:50 pm

okay, wil check the heatercore soon then...

but that means i have to drain the coolant system, also a good time then to check the thermostat.

waterpump couldnt be the issue, just swapped in the ZE last spring and ofcourse then replaced the waterpump. just driven 4000km with it or so, so i hope the waterpump lasts a little bit longer..

will check if its recirculating or taking in fresh air, whats the big difference then?

when on fresh air its sucking in fres air from under the wipercover, and on circulation its sucking air from where?

Tunes67 · Post by **Tunes67** » October 22nd, 2007, 5:56 pm

waterpump couldnt be the issue, just swapped in the ZE last spring and ofcourse then replaced the waterpump. just driven 4000km with it or so, so i hope the waterpump lasts a little bit longer..

I'll admit that its unlikely to be your issue. However.. just because its been replaced DOESNT mean its functioning the way it should be. For that matter check and make sure your belts are tight and spinning your waterpump pulley as they should be.

Dont bury your head in the sand and ignore a potential problem just because you believe its already been addressed. That was then and this is now.

Tunes67

turbulence23 · Post by **turbulence23** » October 22nd, 2007, 6:04 pm

Tunes67 wrote:
waterpump couldnt be the issue, just swapped in the ZE last spring and ofcourse then replaced the waterpump. just driven 4000km with it or so, so i hope the waterpump lasts a little bit longer..
I'll admit that its unlikely to be your issue. However.. just because its been replaced DOESNT mean its functioning the way it should be. For that matter check and make sure your belts are tight and spinning your waterpump pulley as they should be.

Dont bury your head in the sand and ignore a potential problem just because you believe its already been addressed. That was then and this is now.

Tunes67

point taken

will ofcourse check it when all the coolant is out, isnt a big issue then, but i am alsmost confident that its working.. engine is getting at a normal temperature, not overheating etc...

but will look into it, you will never know

solo_ryder · Post by **solo_ryder** » October 22nd, 2007, 7:29 pm

turbulence23 wrote: when on fresh air its sucking in fres air from under the wipercover, and on circulation its sucking air from where?

Its sucking from inside the car, that is why it is called recirc. and that is why it fogs are you are recirculating the moist air.