I lost consciousness trying to figure out what had been done.
So, if the coolant was changed and now the level is low, did you top it off ?
Could’ve been a big burp of air from the heater core.
Park it grille high when you top it off, after a full coil down!

If that doesn’t do it then , head gasket or other problems are possible

 

Just read through this.
When the T-Stat/coolant was done everybody was happy. Then the problem started again and the blend door actuator was changed. And again it looked like it was fixed.
Now the coolant bottle has nothing in it so start looking for an external leak or the start of a bad cylinder head gasket.

 

When this all started it would work intermintally, meaning I would have heat off and on but now it’s more so that it doesn’t. When I did the t-stat, I thought it fixed it but it didn’t. Life has been busy and weather has been great so I really didn’t have a chance to get back to it.

I installed the actuator yesterday, went and drove the car to get it warm but the heater still worked the same. A bit later I thought to check the coolant level. The overflow bottle was empty and the main filler neck was a bit low. That right there was a concern.....and no there hasn’t been air in the system since the t-stat was done. The system was full when I was done with that job and made sure the air was all out.

After being topped off last night I warmed the car up again, still no change in the heat.

Now what’s a control panel cost? Worth trying one?

 

You lost coolant or never rechecked it's level after repairs.
Get front high ( hill, ramps or on top of a curb) add coolant to radiator fill and leave cap off. Get it up to operating temp to get the air out, as it "burps" add more. When it looks like no more can be added put the cap on, fill the recovery tank and monitor the level in it.
The Chevy Citation had a problem like the HHR and that's what I did in the shop I worked at. Glad they don't make that junk car anymore.
If by chance to get a lot of bubbles all the time with the cap off it is an indication your head gasket is gone.

 

How common is the head gaskets on these? Secondly when having it topped off after it was low, wouldn’t the heater generally work correctly until it went low again? That would be my suspicion.......

I owned and 03 civic that had heater issues similar and it ended up being a head gasket.....fingers crossed this isn’t my current issue

 

quote: "The overflow bottle was empty and the main filler neck was a bit low. That right there was a concern.....and no there hasn’t been air in the system since the t-stat was done.

If the main filler neck showed low, what do you think was in that empty space ?
That right. AIR.
To say there hasn't been air in the system since the t-stat, makes me think your not familiar with how a cooling system functions.

Sorry to be blunt but that's how I see it.

 

The radiator fill is lower than the top of the engine. So that means air will be trapped in the engine block unless you raise the front (rad filler) higher than the engine.
Do this first. Get back to basic's.
Like I said, with the front up and the coolant filled and the cap off, if you see that the coolant get's pushed out constantly, then think head gasket.
Head gaskets can make the engine run "rough" because a spark plug is fowling out. Also if anti-freeze is being burnt you could see white smoke out the back and your oil cap on the inside will be milky.

 

Thank you.

Now back to basics, I know how a cooling system works and how to eliminate the air. My feelings are, once the system has the air out of it and it’s full, that heater should work and it’s not....the temperature setting on the control panel isn’t going to know where the coolant level is at.

I’m not disagreeing that I haven’t had air in the system but I don’t believe that’s the causing issue.....looks like a control panel might be an option, better then tearing the head off.

The car isn’t burning coolant out the exhaust and the oil cap is fine.

 

It could be air trapped in the heater.
Ensure the heater is on full heat when you fill it up.
Yes have it sitting grille high or simply jack up the left front 4 or 5 inches.
Bring the engine to temperature, run the heater full heat full fan.
Shut it off after 10 minutes, let the engine cool completely, over night if possible.
Now when it’s cold, remove the fill cap on the upper radiator hose.
Top off the coolant level . Replace the fill cap.
Lower the HHR if you jacked it up.
Start the engine, only idle for 1 minute or less.
Go for a 5 to 10 mile drive.
Now, repeat the first part
Jack up right front, let cool , check level.
You might need to do this 3 or 4 times to fully burp the heater core.
If you want there are test kits for testing the coolant to determine a head gasket issue.

 

Then go with your gut feelings and do a follow up on the repair.
I do remember you said you would watch the heater actuator work correctly and then it didn't.
I'm always open to learn new things.