No cabin heat at -10 F

elpeters · January 6, 2015

Hello all. Just got this truck 2015 5.3 crewcab. It was -10 (according to the truck temp) the other night and I wasn't getting any/much heat. The blowing air was warmer than outside temp mind you but I turned off the vents because they were too cold to give you an idea.

I remote started for about 5 mins, then drove 30 mph for approx 30 mins. I tried all combinations on the system, auto, non-auto, sync, temp cranked to HI, temp set to 72, etc. with no luck the entire drive. I don't remember if I hit the recirc button. I watched the truck temp gauge as well to make sure it didn't think it was 80 degs outside.

The next day we had around a 30 deg day and it heated the cabin fine. Any ideas? I am taking to dealer this week to check but I doubt they will find anything wrong.

Newell33 · January 6, 2015

I'm not sure about the extent of your problem, but I can tell you that my 2014 is very slow to heat up. In fact, it won't heat up in temperatures below approximately 25 degrees F without driving down the highway for an extended period of time. It was around 17 degrees the other day, and while running errands around town the truck never did get above 180 degrees. This was after 2 remote start cycles in my uninsulated garage. I know there's a thread on here with other owners in cold weather states that have the same problem. This truck is far worse than my 2011, and reminds me of my 2007 Duramax. Every day that goes by is a day that I'm closer to getting something different. I'm just glad that my truck doesn't vibrate, or I'd really be pulling my hair out.

pm26 · January 7, 2015

This sounds like a possible HVAC actuator issue, (blend door actuator to be specific). If these actuator(s) do not move when commanded, warm air will not be diverted into the cabin. Another possibility is a defective heater control valve?

With a crap load of cheap parts GM is using now in climate control systems, it does not surprise me to see these problems. I already had to replace 2 HVAC actuators in my '09 Impala. But at least they failed after 4 years, not the first year.

elpeters · January 7, 2015

Thanks. It's a week old. I see this as a separate issue from the not warming up with remote start. Mine does that as well. I'm hoping they come out with a software update to fix that.. Got rid of my diesel to get faster heat and so far very disappointed.

nuclearxp · January 7, 2015

This sounds like a possible HVAC actuator issue, (blend door actuator to be specific). If these actuator(s) do not move when commanded, warm air will not be diverted into the cabin. Another possibility is a defective heater control valve?

With a crap load of cheap parts GM is using now in climate control systems, it does not surprise me to see these problems. I already had to replace 2 HVAC actuators in my '09 Impala. But at least they failed after 4 years, not the first year.

what he said. next time it may be that cold again, before you turn the vehicle off for the night, change your temp to half hot half cold then shut the vehicle off. what I'm hoping is that'll leave the blender door off any edges where it may be shutoff cold, gather condensation, and freeze in its place.

Imcrazy · January 7, 2015

It was 15 degrees this morning and my truck was warm by the time I reached the end of my street which is about a 5 minute drive.

DRS 95 Silverado · January 9, 2015

About 10 - 15 (had a low of 5) when I drove mine today. Was in unheated garage couple weeks since I ran it. Thought it warmed up pretty good. Only thing I didn't like, when it was on auto it was throwing some air out the defrost vents. Windshield was clean so I hit the button and put it all to the floor. Normally I just leave it on auto.

Don't think you have any valves in heater hoses. If keeps acting up take in it and leave it there over night if possible so they can try out with the engine cold.

austingta · January 9, 2015

We had 23* F this morning (I know...don't laugh too much), and I turned on the seat warmers for the first time...never did really heat up. The heated steering wheel got warm very quickly.

It seems the heaters on these things don't work very well.

nuclearxp · January 9, 2015

About 10 - 15 (had a low of 5) when I drove mine today. Was in unheated garage couple weeks since I ran it. Thought it warmed up pretty good. Only thing I didn't like, when it was on auto it was throwing some air out the defrost vents. Windshield was clean so I hit the button and put it all to the floor. Normally I just leave it on auto.

Don't think you have any valves in heater hoses. If keeps acting up take in it and leave it there over night if possible so they can try out with the engine cold.

There is an option buried in your head unit, from the home screen, somewhere under HVAC that will throttle the "Auto Max Fan Speed" to low/mid/high. My wife also hates the cold blast from the Auto setting so I dropped mine to Low. I think it is a mild tradeoff that it'll probably just put warmer air out slower but may minimize this effect on you.

DRS 95 Silverado · January 9, 2015

There is an option buried in your head unit, from the home screen, somewhere under HVAC that will throttle the "Auto Max Fan Speed" to low/mid/high. My wife also hates the cold blast from the Auto setting so I dropped mine to Low. I think it is a mild tradeoff that it'll probably just put warmer air out slower but may minimize this effect on you.

I think I have mine set to med max. Normally I find auto fine but yesterday it was unusually cold here and I just hit the button to throw all the heat to the floor. Overall I'm satisfied with the way it works. Seats seem a little slow to warm up but worked. Heating wheel works good. Not driving mine much yet. Driving my old truck over to plant (gets pretty filthy sometimes) till I retire, then I'll just have the newer one.