1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Heater Core Flush

Discussion in 'Audi S4/A4/A4 Cab (B7 Chassis)' started by Wrath, Mar 25, 2012.

  1. Wrath
    Offline

    Wrath Well-Known Member

    Joined:
    Apr 7, 2009
    Messages:
    1,186
    Likes Received:
    39
    Realised on a long journey "farn sarf" that my climate control doesn't provide much heat, it's lukewarm at best. After ignoring the missus going on about "there's cold air hitting me again" for a few weeks, I finally realised she was right....but don't tell her.

    I want to try flushing the heater core but I have two questions:

    1) Halfords sell a VW 5ltr bottle of coolant, how much coolant is required from empty? Do I need that much or can I get some VW stuff off ebay in 1.5ltr bottles?

    2) Where is the easiest place to get the required hose. It looks like I need 20mm/21mm or 22mm diameter hose but clearly don't want to buy an entire reel for 50 quid?
    #1
  2. raffhussain
    Offline

    raffhussain Member

    Joined:
    Jul 14, 2011
    Messages:
    89
    Likes Received:
    4
    Hey wrath, u won't need much g12. Your are just flushing the heater core which won't have much g12 standing inside it. The water passes through the core and back to the engine. If you flush on cold engine the core will have minimal water in there. When you flush the water standing in the core will come out along with gunk. No water will leak from the inlet and outlet pipes so you won't lose much coolant. Try a lock DIY store for some pipe. If you can't get any then just do it without the pipes. I did this for a friend and it was fine. He didn't lose much coolant and it worked fine.
    #2
  3. Wrath
    Offline

    Wrath Well-Known Member

    Joined:
    Apr 7, 2009
    Messages:
    1,186
    Likes Received:
    39
    Cheers mate. Managed to get some pipe so will try this shortly.
    #3
  4. Wrath
    Offline

    Wrath Well-Known Member

    Joined:
    Apr 7, 2009
    Messages:
    1,186
    Likes Received:
    39
    After borrowing some tools from B5Nut, got the top pipe off (took half an hour!), got the battery out (which nearly broke my back) but couldn't remove the lower pipe. Tried for half an hour but got worried I was going to split the hose. Put it back together and will go forward with B5's suggestion to remove the lower radiator hose and flush the whole system. At least in that case I will be removing all the crud.
    #4
  5. Wrath
    Offline

    Wrath Well-Known Member

    Joined:
    Apr 7, 2009
    Messages:
    1,186
    Likes Received:
    39
    Update: Wasn't straightforward, had to remove the thermostat and one of the torx is in a **** place. Managed to flush the system out properly, refilled (took about 2L G12++ and 2L water thereabouts). Heater works wonderfully now!
    #5

Share This Page