My Heating is on the fritz

I can’t turn it off, the place is like a greenhouse and my hot water is bubbling away merrily.
Even when I turn the thermostat down to zero it doesn’t help and nor does taking the fuse out that controls the heating system.

So I phoned a “Tradesman” yesterday and he promised to be here between 12 and 3.30.
It’s now 5.30.
I phoned him about 15 mins ago and the conversation went like this

ME: Where are you?
HIM: I’ve just ordered the part
ME: What fucking part, you haven’t even called round yet
HIM: Erm Yes that’s true
ME: So how do you know what part to order if you haven’t even seen the job
HIM: Err I just do
ME: Well in that case psychic one tell me what my next words to you will be
HIM: Don’t bother
ME: Wrong, they are piss off you useless twat.

…and he wanted a £50 call out fee