no heat in a 99 blazer

I have a 99 blazer that blows lukewarm air at best.

The engine seems to be running at normal temps (what is the normal temp anyway?) so I'm guessing it's not a thermostat problem.

From the posts out there that I've seen, specifically the one by bowtiebandit, this problem seems to be caused by buildup in the cooling system usually due to the manuafactures use of the "orange" coolant. I'm assuming the best solution is to try the flush he suggested?

Is replacing the heater core really necessary? Probably should check it anyway while the system is drained?

Thanks,
Ryan

If you are getting luke warm air, some of the fluid is getting through. The same thing was happening with mine. I did a simple plain water flush to see if the heater core was partially plugged and it was. I had plenty of heat. I then followed the instructions that you read from bowtiebandit. It worked out pretty good and is a pretty inexpensive fix.

Good luck.

If you werent getting a smell of burnt antifreeze then i isnt your heater core or a puddle under floor mat go with the flush.
good luck