Charger error

Eager to get my ebike charged to be able to try out the next day, I ended up soldering the connections to the charger last night in the wee hours of the morning. I managed to wire the connector on my battery box with the polarity backwards. When I connected the charger to the box, I heard an unpleasant pop sound and immediately knew I had screwed something up. I sent an email to Ping, and he responded later with a reassuring "Don't worry, we will help you solve the problem". Ping helped diagnose the problem as being the charger and said he would send me a new one, no charge, even though I explicitly said I had caused the fault. My experience with Ping as an eBay seller so far has been outstanding.