King Street Spas & Pool Supplies

We bought a heater from them last weekend. Owner said most likely Wednesday for install. When I had not heard from him by Thursday, I called to follow up and he said he would be by that evening (actually his exact words were "I will get my a$$ there today")
He arrived around 7pm, we were eating dinner. Tim went out to let him in the gate and then came back in to finish dinner with us.
A while later we looked outside and he was gone. Old heater uninstalled and sitting in our driveway, no new heater to be found.
I figured he got called away, we are pretty patient, so I gave it till Friday afternoon then called the store. They said he would call back, he did not.
We went in today, because our pool hoses are now loosely connected and leaking, and frankly we do just want our heater. The girls in the store called him and handed me the phone.
What transpired next was accusations, after accusation of him saying Tim hid the bag of connections for the heater, then he hung up on me.
In shock, and not sure what to, we asked for a refund, which they said they could not process a refund. In the meantime the owner called back and said he would send us a cheque, which I flat out refused. I was not leaving the store without a credit on our card, so he told us we would be there till Monday.
At this point I basically broke down as he hung up on us again.
About 10 minutes later he came busting through the door in a shop full of people, and started screaming at my husband calling him a F-in Lyin@ Ba$tard.. yup.. verbally attacked him for something that makes no sense and we have no idea what he is talking about. My husband said "Why would I sabotage my own heater install"
He then asked us to leave, Again I refused and said he better get me a refund or he would have to call the police to have me removed.
After an hour I finally left with a refund and a ban from the store, at which I laughed at that he would actually think I would ever step foot inside again.

Honestly, we bought a heater.. not sure how that made us the bad guys.

Funny part was, no less than 4-5 customers who witnessed this said they have had terrible customer service from him. So why keep going back and encouraging this insane behavior??