Air conditioning Hack

[KcRay]

Today I was able to get 36-38 degrees blowing out of both the drivers side and the passenger side ac vents. Previously I was getting 44 out of the passenger side and 50-52 out of the driver side. I installed a water shut off valve in the heater hose going from water pump to the heater core. It's the outbound side of the pump says "out"right on the hose. This stops any hot water from getting into the air conditioning system at all. You will have no heat when the valve is closed, for the heater you will have no way to control the air conditioning temperature it will be as cold as it can be. This was only a test for me if you decide to do this it will be at your own risk. In essence this proves there's definitely a blend door issue inside the dash letting hot water into the HVAC system when we are telling it not to

 

[Ddelallata]

Awesome! Thanks for having the guts to try this out.

 

[Zeronet]

Does that valve allow you to partially open it so that you could reduce but not completely cut off the flow? Could that allow the a/c system to adjust cabin temperature?

 

[heydre]

True problem solving in action....KcRay!
Good question Zero...

 

[KcRay]

Does that valve allow you to partially open it so that you could reduce but not completely cut off the flow? Could that allow the a/c system to adjust cabin temperature?

Yes, you could open it just a bit. I'll try that today.see what the temps are then

 

[Nails]

Nice thinking outside the box!!!

 

[YoAdrian]

Today I was able to get 36-38 degrees blowing out of both the drivers side and the passenger side ac vents. Previously I was getting 44 out of the passenger side and 50-52 out of the driver side. I installed a water shut off valve in the heater hose going from water pump to the heater core. It's the outbound side of the pump says "out"right on the hose. This stops any hot water from getting into the air conditioning system at all. You will have no heat for the heater you will have no way to control the air conditioning temperature it will be as cold as it can be. This was only a test for me if you decide to do this it will be at your own risk. In essence this proves there's definitely a blend door issue inside the dash letting hot water into the HVAC system when we are telling it not to View attachment 25616 View attachment 25617 View attachment 25618 View attachment 25619 View attachment 25616 View attachment 25616 View attachment 25617 View attachment 25618 View attachment 25619 View attachment 25616 View attachment 25619

Interesting info regarding the potential source for many climate control problems, nice work.

Last summer this site collected a lot of owner complaints about insufficient cooling air and weird/incorrect climate control logic. My AC is certainly not “ice cold” like my other vehicles, and just yesterday I was commenting to my wife about how the climate system seems to take inappropriate actions based on ambient vs commanded temps.... I wonder if the blend door problem you are discussing is related?

I wish there was a way for @RamCares to point Ram engineers at a post like yours above @KcRay to briefly review how shutting off a line like you did drastically improved the AC performance. Maybe it could provide them a direct path to fixing a problem that we’ve heard exists in many trucks, as evidenced by the complaints and service calls last summer.

I suspect these climate control complaints and service calls will increase again soon and Ram will be hearing a lot about it... would be great to help them get a leg up on a fix. But how do you get their ear? Must it be through a star case?

 

[KcRay]

Yes, you could open it just a bit. I'll try that today.see what the temps are then

Opened the valve 1/2 turn to let in a bit of hot water this am. Got some 90* heater temp blowing and ac temp down to 44* coming out the drivers vent. So yes you can actually fine tune your own blend by adjusting the water valve, and get some sort of personal comfort, other than only having 36* blowing at you.

 

[REBEL 2.0]

Opened the valve 1/2 turn to let in a bit of hot water this am. Got some 90* heater temp blowing and ac temp down to 44* coming out the drivers vent. So yes you can actually fine tune your own blend by adjusting the water valve, and get some sort of personal comfort, other than only having 36* blowing at you.

Please keep us updated periodically, even if there are no changes in performance. Good job!

 

[Flot]

I am not looking at my truck right now, but wouldn’t it make more sense to install a “u” into the heater core line so that you aren’t changing the flow from the water pump? That way the water will pump towards the core and return just as it would before. (Maybe it is a simple Tee off the main lines so this wouldn’t matter). They do sell adjustable bypass valves like this, although I don’t know that I’d want the added complexity. There are plenty of U hose kits on ebay etc.

What is the diameter of the heater core line? Asking for a friend.

If anyone does this, don’t forget to cap off the heater core as well.

I’m not surprised at the results, in most vehicles the heater core is practically right next to the AC evaporator. I do wonder if there is any increased risk of evaporator freeze up or similar.

I’ve still got my fingers crossed that my dealer will perform the AC TSB next time I go in for an oil change. I will say that after my last trip to the dealer I could swear that I heard the cooling fans on high much more than I used to - not sure what update might have influenced that or if it is just my imagination.

 

[KcRay]

I am not looking at my truck right now, but wouldn’t it make more sense to install a “u” into the heater core line so that you aren’t changing the flow from the water pump? That way the water will pump towards the core and return just as it would before. (Maybe it is a simple Tee off the main lines so this wouldn’t matter). They do sell adjustable bypass valves like this, although I don’t know that I’d want the added complexity. There are plenty of U hose kits on ebay etc.

What is the diameter of the heater core line? Asking for a friend.

If anyone does this, don’t forget to cap off the heater core as well.

I’m not surprised at the results, in most vehicles the heater core is practically right next to the AC evaporator. I do wonder if there is any increased risk of evaporator freeze up or similar.

I’ve still got my fingers crossed that my dealer will perform the AC TSB next time I go in for an oil change. I will say that after my last trip to the dealer I could swear that I heard the cooling fans on high much more than I used to - not sure what update might have influenced that or if it is just my imagination.

There is a bypass hose going from water pump to the engine block. This bypasses or parallels the heater core as needed. So no real need to make your own bypass hose.

 

[RPeezy]

You're doing good work KcRay! Thank you for your efforts!

 

[I Love Grits]

Thanks for taking the time to do this!

 

[Jhill]

I have spread the word in private message to RamCares to please share this info to the engineers that it is an obvious blend door issue. They agreed that they would. I have also emailed TFLtruck and got a reply from Andre Smirnov that they will look into AC temps as they haven't experienced warm weather yet. I also told him results of shutting down coolant flow. I am sure informing these 2 sources should "turn up the heat" on the engineers for a resolution.

 

[Jhill]

Today I was able to get 36-38 degrees blowing out of both the drivers side and the passenger side ac vents. Previously I was getting 44 out of the passenger side and 50-52 out of the driver side. I installed a water shut off valve in the heater hose going from water pump to the heater core. It's the outbound side of the pump says "out"right on the hose. This stops any hot water from getting into the air conditioning system at all. You will have no heat for the heater you will have no way to control the air conditioning temperature it will be as cold as it can be. This was only a test for me if you decide to do this it will be at your own risk. In essence this proves there's definitely a blend door issue inside the dash letting hot water into the HVAC system when we are telling it not to View attachment 25616 View attachment 25617 View attachment 25618 View attachment 25619 View attachment 25616 View attachment 25616 View attachment 25617 View attachment 25618 View attachment 25619 View attachment 25616 View attachment 25619

This is right up there with landing on the moon! You are our hero for being first to McGyver a temporary solution. I have promoted you in every AC post I find. Maybe Nobel prize worthy? Fat guys everywhere can now stay cool!

 

[TruckDriver]

That's a pretty interesting solution @KcRay ; if anything I'd suggest crack that valve open 10% at the least to ensure you don't have stagnant water in your core.

Too bad you have to do this in the first place - I haven't had a hot enough day to need to crank the AC but I'll keep a gauge handy when I do

 

[Jhill]

Here are more coolant valve options....the Vintage Air $88 unit is electronic and gives you total control of valve variable adjustment from inside with a potentiometer knob. Way cool! Others cheaper units could have a pull cable to open/close valve. Maybe Ram will offer a $500 option to have it from factory in future. lol

 

[Nails]

This is way older Toyota’s & fords had some of coldest ac out there. Damn well freeze you out of the cabin

 

[MEL T]

the 4 seasons valve 74827 reminds me of the heater control valve on my 1967 dodge dart, that I bought new and was my first car. It was a 273 cu iin 2bbl 4 speed

 

[KcRay]

That's a pretty interesting solution @KcRay ; if anything I'd suggest crack that valve open 10% at the least to ensure you don't have stagnant water in your core.

Too bad you have to do this in the first place - I haven't had a hot enough day to need to crank the AC but I'll keep a gauge handy when I do

You have a good point.

That's a pretty interesting solution @KcRay ; if anything I'd suggest crack that valve open 10% at the least to ensure you don't have stagnant water in your core.

Too bad you have to do this in the first place - I haven't had a hot enough day to need to crank the AC but I'll keep a gauge handy when I do