ACC System

[Rocky]

Does anyone know what controls the flow of coolant into the heater core?

As far as I know, when you want cold air, the heater core is drained of fluid. When you want heat, coolant is flowed into the heater core. I'm trying to diagnose a problem I have.

If your interested, read on.

When my ACC is set to about medium temp, I can hear water sloshing around in the vents in the centre console. When the heat is on HIGH, I hear a rush of coolant entering the heater core. This leads me to believe the device that controls the flow of coolant is faulty. Please correct me if i'm wrong.

Also looking at replacing the ACC Dual Valve soon. This device regulates the air coming out from the side vents and the centre vents. With the AC on, warm air comes out the centre vents which I believe the ACC Dual Valve diaphragm is busted or sticking.

Last problem, when i trun my fan all the way to high, it maintains HIGH state for about 2 seconds before it goes to meduim while it's still set on high. I believe this might be a fan regulator on the blower motor.

Wish me luck,

thanks in advance

rocky

[J Irwan]

rocky

just curious, when and why did you actually set the HEAT temp on "high"

I rarely have to adjust my climate control temp during summer and winter.

it always stay between 68 and 71 for both summer and winter..





Regardz,

[SLAMMED_C]

Your statement is incorrect...

As far as I know, when you want cold air, the heater core is drained of fluid. When you want heat, coolant is flowed into the heater core.
The heater core always has coolant in it.

The flow of coolant in the heater core is controlled by the mono valve (on single zone cliamte controls) or a duo valve (on dual zone climate controls)
when you slelect more heat say on the drivers side, the left side valve will pulse as needed to flow hot coolant into the heater core, if no heat is requested, the valves do not pulse, as no heat was asked for (in say a/c mode)
but as heat is needed, the valves will pulse to continue to let more hot coolant into the heater core to maintain the temp that you requested for, and so one if the controls are adjusted on the passenger side.
there are also lots of flaps, mix flaps in the heater/ac box that mix cooler outside air with the hot heater core to deliver the desired temp selected by the driver.

Now, for the warm air coming out the vents when you put it on a/c.. Id say there is no freon charge in your ac system, I would start with that.

And finally, with your fan speed changing on its own, Id say the voltage regulator on your blower motor.

[Rocky]

Originally posted by J Irwan
rocky

just curious, when and why did you actually set the HEAT temp on "high"

I rarely have to adjust my climate control temp during summer and winter.

it always stay between 68 and 71 for both summer and winter..





Regardz,

Irwan, cause up in Canada, we get -30C temps (close to 0F).

Slammed C: thanks mang...i'll check the freon(134a) but I doubt it cause the centre vents blows cold air and the side vents warm. I'll change the the voltage regulator.

BTW, is it easy DIY job to change both?