WGB in Toronto

I've learned my lesson, hopefully someone else can learn as well. I called the Whirlpool service desk about my dishwasher that wasn't washing as well and was routed to TAS. The appointment was set-up without fuss and the tech arrived on time. I should have sent him packing when he said 'that's a unique machine' as he looked at my Whirlpool dishwasher, but unfortunately didn't. After some fuddling around and confused looks he called someone on his cell phone and spoke for a few minutes. The diagnosis was a component that he said would cost $220 which they would contact me about and he'd come back to install (for more $). I waited a week and heard nothing, so thought I'd order the part myself to speed things along - learning that the part was no longer available and I'd have to buy a new dishwasher (to replace my 5-year old one). I figured, if it was dead, it wouldn't hurt me having a look. It turns out a float level sensor in the bottom was dirty, so I cleaned it, put it back together and it worked fine. So, I phoned TAS and asked that my $88 be refunded as the diagnosis was completely wrong and almost cost me $800 to buy a new one. I have phoned several times and they have stopped responding. For the principal of it, I will now be taking them to small claims court where I am almost sure to win - more to come. If TAS or their techs feel they are not equiped to diagnose a make or model (which they know before they come out), they should decline rather than taking the money and providing no service - or in my case, taking a stab in the dark at random components that may have cost me a new dishwater.