2001 Chevrolet Blazer Q&A

2001 Chevrolet Blazer Question: I have no heat

The ac works fine and there is no leak in the heater core -
Answer 1
Have you ever removed that red 'crap' it came from GM with called Dex-Cool? -
Comment 1
Yes I have replaced the Dexcool. I have heard this stuff will settle in the lowest point and solidify. -
Comment 2
Possible stuck open thermostat, low coolant level, heater controls or restricted heater core. Replace t-stat first thing anytime there is a heating/cooling problem with the engine which also affects hvac systems. -
Comment 3
I have done all of the recommended except replacing the core., I am about to use air pressure to blow out any clog. -
Comment 4
If it is restricted, i have good luck with air and water together with a rig i made up. Try the air, cant hurt. -
Comment 5
I ran water through it. It flowed fine in one direction but not the other. I was wondering it there is some find of check valve in the system that would prevent the flow in one direction? -
Comment 6
Not that i am aware of. Hook hoses back up, refill rad run until hot and see if both heater hoses get hot. Post results. -
Comment 7
I ran the motor to running temp. The big radiator hose was to hot to touch but both the heater hoses were barely warm. I had no problem holding Them in my hands. I held them close to the firewall. addendum : I ran the air pressure up to 100 lbs. It blew out something, Because I now have heat. Thanks tor the support. Tim -
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