V70 Climate Control Problem

crismit125 · Post by **crismit125** » 26 Jun 2013, 20:45

Hello all, when i set the temperature to full heat warm air is produced but not blown out the vents. All of the vents have this problem. The system sounds like it is under pressure or clogged up. However, the a/c blows cold indicating that the blower motor is fine. I noticed this problem during the winter but have not gotten to fixing it until now.

All help and advice is greatly appreciated, Thanks!

Post by **abscate** » 27 Jun 2013, 03:42

Do you have manual or electronic climate control?

Are you saying if you run the AC, cold air comes from the vents, but if you turn it to heat the air flow stops?

crismit125 · Post by **crismit125** » 27 Jun 2013, 15:29

Thanks for the reply, The climate is electronic dual zone. With the a/c on, air flows out the vents and it is cold like it normally should. However when i turn the heat on air flow stops but i can feel warm air on top of the vents. The problem is that the warm air inst blow out the vents. I find it weird since the a/c is.

Post by **abscate** » 28 Jun 2013, 05:20

That does sound strange. Ill see if I can post a pic of the internals of the Electronic Climate Control - bad damper motor, plugged heater core (air side) perhaps?

Haakon · Post by **Haakon** » 29 Jun 2013, 04:02

I have almost the exact problem as you have, only mine, does not come air out of any air ducts with the ac on. I`ll hope we can sort this out togheter

fiy: heres my post on it: https://www.matthewsvolvosite.com/forums ... =1&t=57214

Post by **abscate** » 29 Jun 2013, 04:27

The path on the ECC is as follow.

Air comes in from either fresh or recirc (controlled by first damper ) all air then goes through the AC evaporator core.

If the requested temp is below ambient, the AC is turned on and the floor, cabin, defrost dampers direct air as chosen temperature regulation is performed by cycling the AC compressor and fan speed with feedback from the cabin temperature.

To heat, the air is directed partially through the heater core. Unlike your old Ford Fairlane , there is no hot water valve on the heater core..it always flows with hot coolant at full flow. Cool air is partially redirected into the heater core and then sent to the cabin. I believe both mix and fan speed are used to regulate heating cabin temp based on my time spent upside down under my dash watching my dampers. See your Doctor if you do this for more than 4 hours.

A plugged heater core (air flow) would obviously account for crismit symptoms. Good news is you can pull the heater core out in about an hour without dash removal

crismit125 · Post by **crismit125** » 29 Jun 2013, 15:15

Im going to take a closer look at it this weekend as well as do some research and report back.

Thanks a lot!

Edit: I also forgot to mention that I loose about 1/5 to 1/4 coolant from the reservoir every few weeks which may lead me to thinking that there is a leak at the heater core. However I checked the floor carpets and they are not damp or wet.

Post by **abscate** » 29 Jun 2013, 17:45

You have to check under the soundproofing material under the carpet. The carpet can stay nice and dry and pool coolant underneath