clacy

Jeff On your 4th picture down it shows two vent doors that bypass the heater core or AC vents. Is it possible that one of these doors could be broke and thus letting cooler air to the drivers side. I have pulled and looked at all 4 of the motors and linkage and have found that they al work as they are supposed too. My passenger side temp is warm to hot, but the drivers side is cool to cold. I have a 2003 Ram 2500, and the temp gauge and thermostat appears to be working as it is supposed too. It goes up to the middle hash mark and then when it opens it comes down just a hair and stays there.

roxj

Do you have the dual temp control? If you do it has 2 separate small doors instead of 1 for the blend.

Jeff in TD

Mine has dual climate controls, so there are two pairs of doors (above and below the heater core) on each side of the HVAC box.

I've heard that being a bit low on charge will cause the passenger side to run warmer, but I'm not sure why, unless all the refrigerant is evaporating as soon as it hits the evaporator (the inlet would be on the side of the box that would mostly get blown towards the driver's side).

clacy

No I have only the single control. All other doors and vents seem to work fine as far as changing air flow. This just blows cold air on the drivers side, and warm on the passenger side. I was wondering if there was 2 doors for the blend and maybe the one was broke, thus letting cold air to blow on the drivers side?

Jeff in TD

On single control trucks there are two doors for temp blend, one above and one below the heater core. They are the ones with one controller working two doors via a linkage.

clacy

Yea this is what has me baffled. I removed the motor and ran the door by hand with the blower motor running. They seemed to be working from feel and both didnt free spin. With out seeing this pulled apart I am wondering if one of those doors are broke on one side thus letting cold air pass through the drivers side venting. Are they one unit with 2 doors attached to the shaft or are they one big complete door? I have stuck foam in my drivers vents to block the cold air, and hopes that the passenger side warms me up.

6 2 Carl

Clacy,

I have the same issue as you. I have have very little heat on the driver side, more heat, but still not great heat on passenger side. I took the whole dash apart thinking I have a blend door issues, only to find nothing wrong. I swapped a motor and door for good measure, only to find no improvement once I put everything back together.

I believe my heater core is plugged, and the cause for my poor heat.

I recently drained and refilled my coolant and back fllushed my heater core. This seemed to help. However the heat performance has slowly been getting worse again.

I think some debris got into my coolant system when I had an engine swap. I plan on back flushing the heater core again and adding some kind of coolant filter off of a big rig.

Carl

clacy

Yea I am at a loss. I hate to rip the dash apart if the doors seem fine. Just trying to figure this out.

Jeff in TD

I think the single control ones have two flaps on each door. Whether it could be broken on one end, I suppose there's no way to tell without taking it apart.

clacy

Now add this to the mix. Tonight I happened to switch the control dial to recert upper vents and recert upper/lower foot vents, and when doing this had warm air from them both, passenger and drivers side. Any other setting I still get cold on drivers, heat on passenger. Any thoughts on this one. Are we still looking at a blend door issue, heater core being plugged, blend door broke on one side???? Any thoughts or ideas welcome.

Jeff in TD

The blend doors should be in a position relative to the heat control setting, regardless of what other doors are selected.

I don't know what you've got going on.

RamGazer

I know this thread is pretty old, but my manual says to have the a/c system discharged and also the link from the first post says to also (or did I read it wrong?). I went to AutoZone today and they were saying I don't need to discharge my system since I won't me removing the accumulator. Will I be removing it or do I not need to?

Jeff in TD

You have to disconnect the ac core, so yes the system does need to be Discharged.

RamGazer

Darn, I was hoping to save $100! That's how much NTB wants to charge me.

Jeff in TD

I think that is about the going rate.

It seems to me it would not have been hard or expensive to design the hvac case for easier service. It could have been modular, so a person could replace a door or heater core w/o having to desturb the evap core, and maybe w/o removal of the entire dash.