DIY: Water (Heater) Valve Replacement

I'm going to change my water valve in a while, any tips how to bleed the system after finishing? Is it the same way as when the expansion tank is replaced?

DIY coming soon

Blowing hot/warm air when the HVAC is set to 16 degrees? My immediate thought was the water valve which opens/closes, allowing hot coolant in the heater core. I assumed the valve was stuck and would not close completely, hence allowing coolant flow in the core. I went ahead and bought a replacement valve from Tischer BMW (USA)

The old one as it was in the car


First I had to remove the airbox to allow some space to work.


Remove 3 push-lock pins for the air intake assembly


Unplug MAF and loosen the big clamp that holds the intake boot on the MAF


Remove the 2 x 10mm bolts that hold the airbox assembly in place


Airbox removed


Unplug the water valve connector


Pull the water valve out of its 3 rubber guides to reveal the 2 hose clamps screws. Use a flathead screwdriver to undo both screws, paying attention which is the upper and which is the lower hose.


The new water valve
Front:


Rear:


Coolant flow arrow


I placed a rag underneath the water valve to catch the coolant and pulled both hoses out. Then I immediately placed the new water valve and pushed both hoses back in place. Screwed both clamps and secured the valve in place. Plug the connector in the valve. Re-install airbox and MAF connector. Job almost done.


Since air was introduced in the system from the partial coolant loss, I bled the system just to make sure. Removed coolant cap, loosened the bleed screw, started the engine and set the heater temp to its highest setting (32 degrees Celcius) in full blast. Setting the temp in the highest setting would open the water valve allowing coolant flow in the entire system. I topped up the coolant with a 50/50 mix of BMW Antifreeze and distilled water so that the indicator would go to the top mark. As soon as bubble-free coolant started to come out from the bleeder screw, I tightened it, turned off engine and replaced coolant cap.


Job done. Now I have outside environment temperature air even when the A/C is off. I'll open the old water valve to see what actually failed. The heater valve connector wires were a bit exposed for some reason so I applied a generous amount of PVC tape for protection.

thank you!!!! i was looking for this as well

I'm planning on deleting that valve since I don't need it. Any thought paraklas?

Well, I can't think of any reason why not. You can make a bypass connection that will either have the heater always on or always off. Why if I may ask you don't need it? Unless you live in Sahara or Antartica?

Ha,ha
I live in Puerto Rico. Average temp here is 85F, so no need for it

so in order for my to bypass it, do i just unplug it ???

Guessing...

Set the temp to the highest and then unplug it to have always on heater
Set the temp to lowest+ac and then unplug it to have always off - cool air

Cheers for that, i've been looking for exactly that info...Top man

Originally Posted by paraklas

Blowing hot/warm air when the HVAC is set to 16 degrees? My immediate thought was the water valve which opens/closes, allowing hot coolant in the heater core. I assumed the valve was stuck and would not close completely, hence allowing coolant flow in the core. I went ahead and bought a replacement valve from Tischer BMW (USA)

The old one as it was in the car


First I had to remove the airbox to allow some space to work.


Remove 3 push-lock pins for the air intake assembly


Unplug MAF and loosen the big clamp that holds the intake boot on the MAF


Remove the 2 x 10mm bolts that hold the airbox assembly in place


Airbox removed


Unplug the water valve connector


Pull the water valve out of its 3 rubber guides to reveal the 2 hose clamps screws. Use a flathead screwdriver to undo both screws, paying attention which is the upper and which is the lower hose.


The new water valve
Front:


Rear:


Coolant flow arrow


I placed a rag underneath the water valve to catch the coolant and pulled both hoses out. Then I immediately placed the new water valve and pushed both hoses back in place. Screwed both clamps and secured the valve in place. Plug the connector in the valve. Re-install airbox and MAF connector. Job almost done.


Since air was introduced in the system from the partial coolant loss, I bled the system just to make sure. Removed coolant cap, loosened the bleed screw, started the engine and set the heater temp to its highest setting (32 degrees Celcius) in full blast. Setting the temp in the highest setting would open the water valve allowing coolant flow in the entire system. I topped up the coolant with a 50/50 mix of BMW Antifreeze and distilled water so that the indicator would go to the top mark. As soon as bubble-free coolant started to come out from the bleeder screw, I tightened it, turned off engine and replaced coolant cap.


Job done. Now I have outside environment temperature air even when the A/C is off. I'll open the old water valve to see what actually failed. The heater valve connector wires were a bit exposed for some reason so I applied a generous amount of PVC tape for protection.

Paraklas your a champ. But I have a question for you.

My upper radiator hose failed recently, spilling coolant EVERYWHERE over my engine bay. After this, I no longer had cold air, even at 16*c. Is it possible that coolant spilt on the heater valve, damaging it and therefore disabling cool air? If so, should I go ahead and replace this part?

Also, part # and $ would be great.

Cheers

edit: also i've noticed (if it helps with the diagnosis of my problem) - when the ac is set to lowest temp (16*c), the drivers side vents are *slightly* warmer than the passenger side (note that I drive a RHD car)

Thanks for the info and photos, I'm cool now.

Originally Posted by dh0licious

Paraklas your a champ. But I have a question for you.

My upper radiator hose failed recently, spilling coolant EVERYWHERE over my engine bay. After this, I no longer had cold air, even at 16*c. Is it possible that coolant spilt on the heater valve, damaging it and therefore disabling cool air? If so, should I go ahead and replace this part?

Try re-bleeding the cooling system for starters. Also, check the AC belt and the pulleys for coolant presence. Coolant on the pulleys will cause the belt to slip, I had a similar issue when coolant was sprayed on the engine belt and caused the battery light to trigger every time I turned the steering wheel. That valve is sealed pretty good, I don't think spraying it with coolant would have any effect on its functionality.

Also, part # and $ would be great.

Got the valve from Tischer

Water hoses/water valve - BMW parts catalog

Cheers

edit: also i've noticed (if it helps with the diagnosis of my problem) - when the ac is set to lowest temp (16*c), the drivers side vents are *slightly* warmer than the passenger side (note that I drive a RHD car)

See my comments in Red
Part Number is:64 11 8 369 805

Great DIY!

I wanted to minimize coolant leakage/spillage during the change of the water valve - so I "clamped" the hoses leading to/from the valve with some needlenose pliers gently held tight with some twine. Not a drop of coolant spilled from the pipes. Note that I protected the hose from the sharp edges of the pliers with some shop towels.

Is the shorter hose suppose to connect to the top and longer house to the bottom of the valve openings?

Is it verified that if you unplug the valve that it will always stay cold? I have an issue where my A/C is always at 59deg F, and it goes off and on hot and cold.

subscribed, will be doing this tomorrow

Thankyou so much for this DIY! And great job!

Changed temp control valve and problem solved. Had 2 repairs shops tell me it was the flapper door which of course involves opening the dash and a days work. Glad I didn't listen. Very easy to do 20 minutes tops.

Originally Posted by karibrich

Changed temp control valve and problem solved. Had 2 repairs shops tell me it was the flapper door which of course involves opening the dash and a days work. Glad I didn't listen. Very easy to do 20 minutes tops.

what was your problem, originally? i changed my water heater valve, and heat is still coming into the cabin, especially when driving local...

Hey dh0licious,
I recently had the same problem you describe losing the top radiator hose. What did you do to correct the issues you were having with your A/C not working properly?

thanks,
Jerry61

Originally Posted by dh0licious

Paraklas your a champ. But I have a question for you.

My upper radiator hose failed recently, spilling coolant EVERYWHERE over my engine bay. After this, I no longer had cold air, even at 16*c. Is it possible that coolant spilt on the heater valve, damaging it and therefore disabling cool air? If so, should I go ahead and replace this part?

Also, part # and $ would be great.

Cheers

edit: also i've noticed (if it helps with the diagnosis of my problem) - when the ac is set to lowest temp (16*c), the drivers side vents are *slightly* warmer than the passenger side (note that I drive a RHD car)