krishen 2 Posted January 28, 2018 Hi, I had the radiator replaced a couple of months ago and since then noticed the heater is not as hot as it used to be. If i was getting 10/10 heat before its more like 7/10 heat now. Could air in the system cause this? Quote Share this post Link to post Share on other sites
1xshaunx1 27 Posted January 28, 2018 The system bleeds itself easily normally,a short run and a top up after usually does it. How quickly does it achieve this heat. If it takes forever and struggling to reach temps could be thermostat stuck open. Quote Share this post Link to post Share on other sites
Supercharged 2 Posted January 28, 2018 Do you have the recall bypass valves still fitted? Quote Share this post Link to post Share on other sites
krishen 2 Posted January 28, 2018 The system bleeds itself easily normally,a short run and a top up after usually does it. How quickly does it achieve this heat. If it takes forever and struggling to reach temps could be thermostat stuck open. Doesn't take long, maybe 5-10 mins to get warm air and then hot air follows very soon after. Do you have the recall bypass valves still fitted? No idea. Will have to check. But can they cause heat temp to drop if they start to fail? Quote Share this post Link to post Share on other sites
seanl82 23 Posted January 29, 2018 What year is your car? The bypass valves we're only fitted to early cars. You can tell if it's had the recall by the fact that one is metal and one is plastic. Does the air get cooler when driving then warm up again when stationary? That's the indication that the stat is stuck open. Worth bleeding properly if you think there might be air in the system though. They're notorious for being difficult to bleed. Just run the engine up from cold with the expansion cap off, alternating revs up to 2.5k then idle for 30 secs each. When idling, massage the pipes to force air to the top. When temp reaches 90, switch off, let it cool the top up as necessary. Quote Share this post Link to post Share on other sites