conflats12

Hi All, not sure is this the correct place to post but I am having an intermittent issue with my 2014 VRS 2.0 tdi Randomly every month or 2 I get a check coolant warning. Check levels and its below min line on bottle, top up and warning goes away. I have checked for leaks to no avail. I dipped the engine to see has oil level risen (it hasn't) I noticed it happens more frequently when the air con is running (but can see any leaks on coolant system). I spoke to dealer and they said to get the water pump replaced. I purchased the car with 43k miles 18months ago and the pump/timing belt was replaced then. Currently have 73k miles on the clock. Anyone come across this before? Don't want to spend €550 on new pump/belt kit if not the issue. Thanks Conor