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Heating problems! ITS COLD!

2233 Views 33 Replies 8 Participants Last post by  6ohPowersmoke
Ok guys so here are my issues. I probabaly should have looked into this before the cold weather but it hadn’t bothered me until temps have been in the 20-30 range.

problem #1 my heat is not working kind of. It was working intermittently the past few months but has gotten worse (or so it seems) while working intermittently it would range from blowing cold to luke warm to hot and all in between with no rhyme or reason. I have checked me degas bottle and the coolant level seemed to be a little lower than normal but not drastically lower than my line. (I checked it after a cold soak) it seems like it wouldn’t blow any type of warm air until the truck was up to temps then would intermittently blow warm. It also seems to blow warmer if I have it set on 80 compared to 90. Could the slightly low coolant level be the cause? Am I correct with what the coolant level should be after a cold soak? My degas bottle has a molded line and I have a sharpie line below that

problem #2 my driver seat heater does not work. Passenger works great and gets hot. Drivers seat has the red light on the button come on but no heat. I have read it could be a bad relay, I do not hear a relay click On when I hit the driver button. Wheee is the relay? How do I change it?

also to note, I have not noticed any coolant leaks so the drop in coolant level, although minor, has me puzzled.

it is deleted and studded with a coolant filter on there
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Are the heater hoses warm soon after you start the truck? and does the heater put out warm air then?

Your blend door actuator could be bad, if the hoses are hot but not warm air in the heater
if the hoses are still not warm after several minutes after start, then you may have a different problem
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Well Ya, ...aren't you asking about the heater?

problem #1 my heat is not working kind of. It was working
The hose on the RH side where it connects to the water pump is the supply
Then runs back to a vacuum valve before entering the heater core
Look for heat there first

The vacuum valve should be in the extended position -- it is only closed when the controls are OFF and Max AC
Soon as you feel heat in the supply line, it should also be in the return -- wait till the heat feels pretty warm to the touch -- then go feel the heater air

You can pop the plug off the heater fan, and key on -- if it is quiet there, you should hear the blend door motor as you operate the temperature -- should move smoothly with no clicking
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I guess I did not convey the idea about the hoses getting hot very well -- the point is the heater hoses (especially the supply) get hot first (before anything else) -- By the time you got to work, everything should have been too hot to hold your hand on, for very long -- At that point the heat in the cab should have been good - and the return hose hot as the supply.

The air blend controls function the same on both types -- just one is a knob and the other is digital

The round part on the valve is the air cylinder -- use your finger and move the lever towards the cylinder -- when you let go the lever should spring back out -- be sure the lever is moving to the full extent -- out is ON, in is OFF
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Hose in in the correct place -- but as stated before you do not use that valve in the winter -- only OFF and Max AC

Most likely you have other problems in the vacuum system -- we need to address your current problem first
pick up a hand held vacuum pump that has a gauge from someplace like harbor freight or amazon -- for testing , later
Is that the pump that’s behind the passenger battery? Could that also cause some a/c problems? Because during the summer I had some a/c do the same stuff. It would get cool but not cold
Title of the thread says it all here "Heating problems! ITS COLD!"
I think you also have Cooling problems ITS HOT

Just a different season -- same old problem

We talked about the blend door -- but little feed back on if it works or not
We have not talked about air flow or if the core is plugged up with junk -- internally or externally

I think until you are willing to do the work -- just gonna have to put up with the HOT and COLD situation
and yeah, vacuum pump plays the role in where the air comes out of the HVAC system, so there is that one also
Had to make the trip to town this morning for some new skins on the old International Dump Truck
Fired the 6.0 up and went in the house to get the Grand Kid ready
Heard the 6.0 idle up, He already had his shoes and coat on, we grabbed a drink of water and out the door
Was 20F at startup, so got the Boy in the truck and popped the hood to feel the heater hoses
Front supply beside the alternator was nice and warn, maybe 120 ish
Return under the degas bottle was a little warm -- the heater was on Auto and was blowing hard at that time
Radiator and upper hose was cold
Heater was putting out warm heat already -- not it will get hotter -- but remember this as only at about 10 minutes form start @20F

Turning the temp down to cold, made cold blow from the heater -- Back to 70F made warm in only a couple of seconds
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