Flushing heater core

  1. Established Member Joined: Dec 2011 Derby Posts: 1021 Posi saxo, flatty, Peugeot bipper, Vauxhall vectra
    #1
    Replaced thermostat on a Renault Clio today as the temp gague was all over the place, replacing the thermostat sorted this. I also flushed the radiator while I was at it. However the heaters inside the car are only blowing "warm" not red hot like my other cars to the point you can't keep you're hand on the vent.
    P.s I bled the system and it isn't as a result of air locks.

    To flush the heater core can I just unclip the 2 hoses going into the car without draining the system? And it's a matter of letting the hose flow through each pipe in both directions until clear? Could this cause air locks in the system? And hopefully that would cure the problem?
  2. Saxperience Post Whore Joined: Apr 2011 Posts: 9100 Amazon green VTR 16v, Inferno RS clio 182
    #2
    You won't lose it all but it'll need topping up and rebleed after. And yes just undo the matrix feeds at the engine side and flush it through both ways. I'd reckon it's an air lock though unless the system was heavily silted up before? Usually the clios bleed up quite easily however


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  3. Established Member Joined: Dec 2011 Derby Posts: 1021 Posi saxo, flatty, Peugeot bipper, Vauxhall vectra
    #3
    well i drained the whole system again, flushed everything out gave the header tank a good clean, it had a layer of sort of rusty dried up antifreeze on the inside of it? managed to scrape majority of it off and clean it out.

    bled the whole system properly however the heaters still don't blow as hot as id expect, maybe the heaters on Clio's are general rubbish?

    Another thing is, the fan never seems to kick in, ever! but the temp manages to stay on half way constatly...
  4. Saxperience Post Whore Joined: Apr 2011 Posts: 9100 Amazon green VTR 16v, Inferno RS clio 182
    #4
    How hot are you expecting? Could be the matrix is partially blocked up so low heat but usually a flush will cure it. I will say however the climate control/heaters on max in my Clio never feel as red hot as the manual system on my Saxo


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  5. Established Member Joined: Dec 2011 Derby Posts: 1021 Posi saxo, flatty, Peugeot bipper, Vauxhall vectra
    #5
    well, in the vectra especially they blow red hot to the extent that you cant keep you're hands on the vents longer than 10 seconds. maybe i just got high expectations but system is flushed and clean now soo ill live
  6. Saxperience Post Whore Joined: Apr 2011 Posts: 9100 Amazon green VTR 16v, Inferno RS clio 182
    #6
    I've found the heater in our Vauxhalls to have been really good. Had a Vectra b, once the stat had been changed the heater was great.
    Shame about the rear of the shell leaking water like a sieve though, the rear foot wells had about an inch of water in them


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