Heater Blows Cold Air

[elambert]

The heater in my 2003 Olds Silhouette Van is not blowing warm air. Even when the van is warm, the heater does not blow warm like it should. The fan blows fine, just cold air. I make sure that the control is on hot. What could the problem be and how in the world can I fix it? I hope it can be done without taking it to the $garage$.
Thanks for your help.

[GregA]

Originally Posted by elambert

The heater in my 2003 Olds Silhouette Van is not blowing warm air. Even when the van is warm, the heater does not blow warm like it should. The fan blows fine, just cold air. I make sure that the control is on hot. What could the problem be and how in the world can I fix it? I hope it can be done without taking it to the $garage$.
Thanks for your help.

Welcome to the forum!

My first step would be to either feel or measure the temperature of the hoses that connect to the heater core after it has warmed up. I believe they are behind and to the left of the master cylinder.

Note: Have you seen those No-Contact Laser/IR Thermometers? Handy tool!

If the hoses are hot, I would say that it is probably and air flow issue (temperature air baffle not moving properly). If you set the fan to LOW and move the temperature setting from COLD to HOT, you should be able to HEAR IT move around under the dash.

If the hoses are NOT hot, it is probably a restriction to the heater core.

One other thing: Since it is a 2003 model, is it still under warranty? Even if it is just over the age or mileage, I would try to get it fixed under warranty.

Let us know what you find.

Take Care,

[Gill YM]

when you take it to the "shop", don't let them replace the heater core. I'ts an expensive job, and in 9 out of 10 issues, it's not necessary.

Usually this is caused by a simple thing like the heater valve (in the core) not working properly or stuck, and is a lot less expensive to replace than the whole core!!

tell me, has it occured over a peiod of time, or was this problem almost instant?

[cdru]

Originally Posted by Gill YM

when you take it to the "shop", don't let them replace the heater core. I'ts an expensive job, and in 9 out of 10 issues, it's not necessary.

Usually this is caused by a simple thing like the heater valve (in the core) not working properly or stuck, and is a lot less expensive to replace than the whole core!!

While I agree that the core is not normally the cause of heat related problems, it should be noted that there is no valve in the heater core. It's just a mini-radiator.

Engine-tempature coolant is always running through it, even when you have the AC on. There is a damper that controls how the air is mixed, the warmer you want it the more air gets passed through the heater core.

[Gill YM]

Originally Posted by cdru

While I agree that the core is not normally the cause of heat related problems, it should be noted that there is no valve in the heater core. It's just a mini-radiator.

Engine-tempature coolant is always running through it, even when you have the AC on. There is a damper that controls how the air is mixed, the warmer you want it the more air gets passed through the heater core.

I think I meant "the damper" thingy. I didn't knoiw what to call it, so I called it a valve! Yeh, you;re right, it controlls the air mixture. Sorry for confusion

[95ragtop]

Don't mean to scare you, but check the coolant level! The heater also blows cold when the cooland is low. If it is low you can fill it, but also check the oil to make sure it's not foamy (coolant in the oil from a bad intake or head gasket). Keep an eye on the coolant level if you had to fill it. If it maintains the correct level, it was just low. If not, have a pressure ckeck done to find the leak. Just a heads up so you don't keep driving it if this is the problem. You'll seize the engine$$$ There are several threads on intake gasket issues.

[testing99]

My van was blowing cold air ...freezing cold air. It turned out to be low on coolant. After adding coolant 3 times to the resevoir and alot of driving to draw the coolant up into the system. Heater now is HOT !

I believe that an air pocket gets stuck in the heater core. I guess i should have added it via the raidiator cap ?



Hope my intake gasket is fine.

[elambert]

WOW! We were ruling out options and decided to go with the cheapest first. (Of course!) Just knew it was going to be an expensive fix, so with absolutely no faith, we checked the coolant level. It was only a little low so we added some with the van running, so it would circulate well. And guess what! It worked! First try and the heater was blowing not just warm air, it got quite toasty in there. Thank you so much for your advice and for saving us $$$.

[Slider63]

Originally Posted by elambert

WOW! We were ruling out options and decided to go with the cheapest first. (Of course!) Just knew it was going to be an expensive fix, so with absolutely no faith, we checked the coolant level. It was only a little low so we added some with the van running, so it would circulate well. And guess what! It worked! First try and the heater was blowing not just warm air, it got quite toasty in there. Thank you so much for your advice and for saving us $$$.

All, Thanks! I had the same problem in my 2001 pop up last night. After checking fuses, googled the symptons and found this forum. Added about a quart of coolant and heat was restored.