No surge tank after 2007 on LT/LS. 2006 has a surge tank which is analogous to the old fashioned radiator tank on top of the radiator it is pressurized. The overflow bottle on other years is not pressurized, coolant flows back and forth from expansion and contraction.
If the surge tank was empty you are very low on coolant it should be filled to the marks. Same with an overflow bottle. Both must have a certain level to function properly.

 

Never had a problem overheating in November (?) only had this for about 2 months now. When I got it I checked the cap on the upper hose and it was full, I did not check the overflow tank.
No surge tank that I have seen. Only caps are upper hose, coolant recovery, oil and brake fluid.

we hit the high temp for today, 7 degrees and getting colder.. Its cold out there.

 

I have 2 Chevy Suburbans and a Pontiac Minivan with a surge (pressurized) tank.

I also owned every year of HHR except for 2010, including a trio of 2006 1LTs. None of them had a surge tank.

I looked in my 2006 Chevy HHR factory service manual, they only describe an overflow tank (coolant recovery system).

Are you sure about the surge tank, donbrew?

Steve

 

I misunderstood this to mean coolant temps being much higher. I don't know why you are being so resistant to this diagnosis. If your engine cooling fan doesn't run when the AC compressor is running, that's a problem.

 

The problem is thqt it is belo zero outside and the fans will not run unless it is above about 30 degrees. Not resistant, just I don't have any way to warm up the outside tempereature until it gets warmer out. Once the weather warms up, I will check the fans.

The fan on my 2009 smart was broken and I din't find it until it got warmer out and I tried the A/C. this morning it is -6 degrees and I am sure the fan is locked out. It does turn freely and in November when it was warmer (outside) it did work OK. Not saying that means it works now but a good possibility. we shal see when it gets warmer out and I can test it. Like I said, No garage, and in Minnesota, we deal with what Mother Nature hands us. This week it is below zero temps. wanna trade??

 

i took a look at the a/c compressor and with the defroster on full, and the snowflake lit, the compressor does not turn, nor does the cooling fan. Temp was-7 degrees so I will have to check that out once it gets warmer.

However...

Drove to work, same route I drove when it acted up, same temp outside and coolant temp did not get over 198 ntil I parked in the parking lot. it went up to 203, then back down so I think the low coolant was the issue. we will check out the a/c and fan when it warms up.

 

Let’s wait until the temperature outside is warmer.

 

But was the fan running when it cooled down?

 

Too flippin cold out to look!

 

Got up to 32 degrees outside after driving to work, tried turning on defrosters and a/c switch, no fan so i am going to guess it may not be working. Coolant temps have been steady around 194-203 (min max) i would like to see that fan come on though...