Hi, the heater in my truck isn't working correctly, one of the 2 hoses that go into the cab goes lukewarm after about 15 mins, the other hose stays cold, I noticed my coolant is at the minimum point, could that be causing it ? I can feel warm air if I turn off the blower, and then turn it on after a few more minutes, and it will blow hot air for about 5 seconds, before the cold comes in again. Any ideas ? I replaced the thermostat last year, do you think the low coolant is the reason ?

Thanks in advance.

 

Fill it up with coolant first. No coolant=no heat.

 

Hi, I filled up the coolant, and still same problem, I noticed that if i put the blower on the lowest setting I do feel warm air, but if I set the fan on 2 or 3 then it's only cool air I get. I tested the pipes again and one is a lot warmer than the other, could it be a blocked heater core, and is there an easy remedy for that ?

Thanks

Steve

 

Assuming you used the correct thermostat (and installed it correctly) it sounds like its' got an air bubble that needs to be burped/displaced with coolant.

 

It can take several engine heating/cooling cycles for coolant to get from the overflow tank into the coolant loop. Just because the tank got filled doesn't mean the system took it into the rest of the system.