[martynz]

Hi,

I have an E93 (convertible) which has a weird heating issue, or not?

Apparently the E93 does not have a heater control valve/solenoid. So this can't be the issue.

If the car is hot there is plenty of hot air coming from all the vents when temp is set to highest. Once I switch on the aircon the air gets cold very quickly. Aircon off the air gets hot slowly again.

I have checked the vents with INPA and they seem to be moving and operating correctly.

Any ideas?
Thanks!

[e91Owner]

Originally Posted by martynz

Hi,

I have an E93 (convertible) which has a weird heating issue, or not?

Apparently the E93 does not have a heater control valve/solenoid. So this can't be the issue.

If the car is hot there is plenty of hot air coming from all the vents when temp is set to highest. Once I switch on the aircon the air gets cold very quickly. Aircon off the air gets hot slowly again.

I have checked the vents with INPA and they seem to be moving and operating correctly.

Any ideas?
Thanks!

I know it sounds very basic, but is the thumb wheel temperature set to cold?

[martynz]

Thanks for checking even if this is basic.

But it is set to high/red.

I have also checked both pipes (inlet/outlet) inside the cabin to the heater core which are hot.

[gbalthrop]

Originally Posted by martynz

... E93... does not have a heater control valve/solenoid...there is plenty of hot air coming from all the vents when temp is set to highest. Once I switch on the aircon the air gets cold very quickly. Aircon off the air gets hot slowly again. [That should ONLY happen if you press the MAX button (which effectively sets both thermostats to lowest setting). It should NOT happen if you turn on Compressor Valve by pressing the "Snowflake" button below the Defrost button. If you are getting cold air when you press Snowflake & light Green LED on that button, then your "Mixed-Air Flaps" (one on each side, controlled by Thermostat on each side) are NOT working to route ALL air through the Heater Core. See Details Below]
I have checked the vents with INPA and they seem to be moving and operating correctly. [NOT sure exactly WHAT you checked, or WHAT values actually appeared on INPA Screen. I would suggest Saving a ScreenPrint and attaching it here so we can ALL see what you are seeing. I attach such a screen from my 328xi as example, and a "Tutorial Quickstart" which explains HOW to save and attach INPA (or other) ScreenPrints for Forum post attachment.]...

Originally Posted by martynz

Thanks for checking even if this is basic. But it is set to high/red. I have also checked both pipes (inlet/outlet) inside the cabin to the heater core which are hot.

I will attach a screenprint of "INPA > IHKA > F5 > F4 Flap Positions" to my next post, so as NOT to ruin margins here. Attached here is a pdf showing how to get started using Functional Jobs, and HOW to save ScreenPrints and attach them here.

As stated, the MOST likely issue is that the "Mixed Air Flaps", Left AND Right, are NOT at high enough % value. That percentage, for EACH, should read ~ 80% or more if you want full heat, and "0" if you want full cooling (MAX) with NONE of the air from the Evaporator/ Cooling coil being directed through the heater core.

The screenprint attached to NEXT post was with ambient temp 3C, both thermostats set on 24C, and as you can see, BOTH mixed air flaps were controlled by the IHKA Module to 80%, and I was getting warm air from the vents.

I would suggest doing the following THREE (3) Tests, saving screenprint of Flap Positions for EACH:

1) Access Flap Position screen via the "Menu Sequence" stated above (let me know if NOT clear how ;-), record approximate ambient temp and cabin temp to let us know (that matters), make sure engine is warmed by idling at least 5 minutes, make sure Snowflake LED is Lighted (Compressor Valve Active), turn BOTH thermostats to highest, give system time (~ 30 seconds) to adjust to settings, and save screenprint of flap positions at those settings.

2) Then, Press MAX button in center of thermostat (L on US models, but perhaps reversed on yours) and see if you now get cold air and save screenprint of flap positions.

3) Finally, turn OFF MAX, but make sure Compressor Valve "Snowflake" LED is still lighted; Press "Defrost" button above "Snowflake", feel air flow to windscreen and temperature of that air; save screenprint of Flap Positions at those settings.

Provide us with those 3 ScreenPrints and we can suggest next steps.
George

[gbalthrop]

Attached is INPA ScreenPrint saved at temperatures & settings described in prior post; 3/2007 328xi

George

[martynz]

Hi gbalthrop Thanks for the additional information.
I will run some extensive tests with INPA this weekend and hopefully sort this out before the winter comes. Cheers!

[martynz]

This is the test run under number 1. AUTO. HIGHEST TEMP and AIRCON is ON

[martynz]

This is MAX COOL

[martynz]

Number 3. Defrost

[martynz]

Is it possible to inspect the movement of the flaps physically? I tried with a USB endoscope camera but could not see anything moving. But I can hear that something is moving when changing the temp.

Also the middle vents blow slightly warmer air on the right side than on the left side.
The flaps are showing they they move from 0% to 100%. Could that be a false reading?

If I set the temp to highest and the blower to max the air gets colder and colder even when driving as if the heater core does not get enough hot water pumped through?

With engine very hot the hot air measured on the sensor shows only around 40 degrees Celsius which is 104 fahrenheit.

The winter is coming in my region slowly in 3 months and I will be freezing soon.

[martynz]

gbalthrop Hi George, not sure if you had a chance to look at my findings. Cheers!