My HotTop was used a lot for about 6 months from new last year, and then I put it in the cupboard, deciding to let Steve do the hard work of roasting for me. Primarily, I did this because I was having so many problems with my shots, that I just needed to junk some variables out of the equation while I put the world to rights.
But I digress. Anyway, my shots are a lot better now and I was wanting to get back to roasting. For a long time, I'd wanted to mod my hottop with my own control circuit, probably laptop-based, but I knew it would be a decent sized project, and my day job and kids just eat up too much of my time right now. So the "P" upgrade at a lower price than it was originally, seemed like a good idea to gain a bit / a lot more control.
Electronics doesn't scare me, and I'm handy with tools, so I figured I ought to be able to do it.
Anyway, I figure I can summarise the experience as follows:
The high points:
1. It works ! First test roast went through fine. And I actually programmed it with a small child under one arm (not essential to the process) and without the user manual. Although my backround in lifting small children and programming stuff, probably helped there
2. I think it took about an hour and a half to install the upgrade.
3. Mine was the easier version of the install because my HotTop doesn't have the chaff tray safety switch, which can necessitate some extra work to rewire
The low points:
1. For the price of the upgrade, you'd think the manufacturers could provide a printed copy of the installation instructions
2. Ditto the operating instructions, although I kind of get the impression the upgrade boards were out before the manual was actually finished.
3. There's a bit of a gap in the instructions when it comes to removing the base of the HotTop, which you need to do to access all the fixing screws for the internal circuit board. Basically, it tells you to remove 4 screws in the base, 2 of which are obscured by the rubber feet. And then gently wiggle the top and base apart ensuring that you don't pull or trap any wires.
i) They don't mention the fact that there is an earth wire which connects the mains lead anchored to the base, to some metalwork in the top half. This needs unscrewing before you will be able to get the 2 halves apart. (And putting back afterwards!)
ii) Because of the way (i) is done, you also need to cut some cable ties on the wiring harness, which will need replacing at the end.
iii) They also don't mention that apart from the screws, there are some plastic lugs effectively anchoring the base to the top, at the top corners of the plastic panel underneath the bean exit chute. These are pretty hidden and are not that strong. When I eventually found them, it transpired that the best way to unhook the lugs from their receptacles was to unscrew the screw on the control panel side which becomes visible when you remove the control panel (middle left looking at the control panel) and the one at the same place on the opposite side of the HotTop, obscured by a rubber plug. This allows you to ease the sides out and the lugs come free. But you wouldn't get any of this from the instructions !
Turns out, despite my care, and my realisation that there must be something else anchoring top and bottom, I'd weakened one of these lugs, and it rewarded me by snapping when I came to put it all back together again. And I was very careful to try and avoid this. Though you can't actually tell this has happened, everything is tight after I put it back together.
Other than that, it's not a hugely onerous process. The electronics part is actually relatively easy really, as you're just replacing wires to the same numbered points on the new board, removing and reconnecting the earth wire, and fitting some new cable ties. As I mentioned briefly, I didn't need to worry about the extra steps for the chaff safety switch, so I can't comment on that. The hardest part for me, was separating the 2 halves of the machine, and it's a shame that this part is so poorly documented - it just took me ages.
Initial impressions of the new version are very favourable, although I wondered if they could have actually made the UI more streamlined to require a less fancy screen and programming, and maybe charged a lot less for it ! Perhaps I really should design my own version
If anyone is contemplating the upgrade board route and wants to ask me anything else about the install, then just shout.
Jon
