Heat issue

[ljblue]

2006 Silverado crew cab 4x4.  I had some issues over the summer. Blowing hot air all the time.  Ended up just being the blend actuator.  I replaced the hvac control module as well as the resistor (my 5 fan speed wasn't working).  Everything has been fine til the last few weeks.  Now that it's cold, of course the heat is giving me fits.  It's really odd. Sometimes, everything works just as it should.  Sometimes it will only blow cold air, but at any second, it can immediately go to hot.  The truck blows the same temp through the dash/floor/defrosters.  So if its blowing cold, they are all cold.  When it decides to blow hot, they all blow hot.  Sometimes it will be working fine, i'll stop to get gas, jump back in and it will blow cold.  Sometimes it will stay cold for the whole ride home, others it will take a minute or 2 and blow hot.  It's so random.  Anyone run into a similar issue?  One more thing...when it is blowing cold, if I move the setting on the control to hot, the air does feel slightly warmer, but still fairly cold...if that makes sense. Not even sure where to start.

[txab]

Sounds like the temp actuator is bad and is in need of replacement

[GMC-AT]

+1 .. I just did both these actuators on my 2000.  They are both cheap and easy to replace..close to each other. 

[Northman]

Does the actuator connect to a cam type device that opens the doors? Is it possible the connections from the door to the actuator have come unhooked and the door is just flopping back and forth?

[davester]

The actuator directly turns the door.  It is possible for the door to be broken, but that is much less likely than the actuator failing.

[carnau]

8 hours ago, ljblue said:

2006 Silverado crew cab 4x4.  I had some issues over the summer. Blowing hot air all the time.  Ended up just being the blend actuator.  I replaced the hvac control module as well as the resistor (my 5 fan speed wasn't working).  Everything has been fine til the last few weeks.  Now that it's cold, of course the heat is giving me fits.  It's really odd. Sometimes, everything works just as it should.  Sometimes it will only blow cold air, but at any second, it can immediately go to hot.  The truck blows the same temp through the dash/floor/defrosters.  So if its blowing cold, they are all cold.  When it decides to blow hot, they all blow hot.  Sometimes it will be working fine, i'll stop to get gas, jump back in and it will blow cold.  Sometimes it will stay cold for the whole ride home, others it will take a minute or 2 and blow hot.  It's so random.  Anyone run into a similar issue?  One more thing...when it is blowing cold, if I move the setting on the control to hot, the air does feel slightly warmer, but still fairly cold...if that makes sense. Not even sure where to start.

Do you have dual controls? Like drivers and passenger temp settings?

Check the coolant level. Sounds to me like you're running low on coolant. 

 

If you have dual controls and both sides are cold or both sides are hot then it's likely not an actuator. 

[ljblue]

On ‎12‎/‎28‎/‎2017 at 10:43 PM, carnau said:

Do you have dual controls? Like drivers and passenger temp settings?

Check the coolant level. Sounds to me like you're running low on coolant. 

 

If you have dual controls and both sides are cold or both sides are hot then it's likely not an actuator. 

Thank you sir! You nailed it!  I didn't feel like it was the actuators since ive messed with them a lot recently and it was acting different.  I was low on coolant.  Heat is working great now.  I feel kinda silly!  Now I'm trying to figure out WHY I was low on coolant.  Thanks again!

[carnau]

1 hour ago, ljblue said:

Thank you sir! You nailed it!  I didn't feel like it was the actuators since ive messed with them a lot recently and it was acting different.  I was low on coolant.  Heat is working great now.  I feel kinda silly!  Now I'm trying to figure out WHY I was low on coolant.  Thanks again!

Np! Glad you got heat! It's extremely cold outside! lol. These vehicles are prone to two different leaks.

 

One: The common water pump failure. Look behind the water pump and you will see a trail of water leaking down. Sometimes it burns off and never makes it to the ground.

Water Pump - http://amzn.to/2DS6WaU - $65

 

Two: The heater core hose pipe fitting thingies. They connect to the end of the heater core on the passenger firewall. Need a special tool to get them off but you can get it cheap.

Fitting - http://amzn.to/2CfZPIE - $9

GM Tool - http://amzn.to/2CagvkZ - $12

Lisle Set of tools that works just as good - http://amzn.to/2CGqlfw - $10 

 

Glad I was able to help! Make sure to hit those like buttons!