Go back and tell them to get a decent mechanic instead of a monkey, halfords auto centres (nottm hucknall) did my air con service (drain and refill, deodorise) at my mot for free.
If i'm not mistaken, they are in front of the rad on the right as you look at the rad.
I'm having a beer so not going near my car as it is the wrong direction from the fridge, and it is in the garage.
I'm being lazy today