humanoid37 Junior Member Joined: 27 Oct 2009 Posts: 3 Location: Cape Town, South Africa Expertise: I love coffee
Posted Tue Oct 27, 2009, 5:09am Subject: Zaffiro way too hot - Thermostat broken?
Hi
I'm new here and to the coffee underworld so pls bear with me :)
I recently purchased a second-hand Zaffiro from a guy who seemed to know a lot less than me even about his machine (believe it, its possible!), based on the espresso's he was making me with the machine on steam setting?! He also didn't bother to tamp... Either he was acting dumb to hide the machine's defects, or he really had no idea. Either way, the end result was that I paid the equivalent of $450 (a fair price I think) for the machine and now I'm checking to see what needs replacing (yes it's somewhat backwards... it was an emotional purchase).
I've just checked temps using the foam cup method...
Once it's warmed up (gave it 20 mins, a bit short but I was in a hurry) it heats for about 45 seconds and rests for 5 mins, which I believe is standard for a Zaf (insight from forum). Problem is the bottom to top of cycle temps are 97.7 deg C to 98.5 deg C (or 207.9 F to 209.3 F) which although nice and stable is basically boiling temperature (and yes, little plumes of steam come out at the same time)...
So should I start fiddling with the thermostat adjustments, or would I be wasting my time (ie. is the thermostat definitely broken based on my observations). The fact that it's cycling and maintaining a tight zone makes me think perhaps it just needs adjusting... but why on earth would it be set so high?
humanoid37 Junior Member Joined: 27 Oct 2009 Posts: 3 Location: Cape Town, South Africa Expertise: I love coffee
Posted Wed Oct 28, 2009, 1:33am Subject: Re: Zaffiro way too hot - Thermostat broken?
Update:
I adjusted the thermostat down, warmed up the machine and pulled 46 "shots" (50-60ml/ doubles) every 45 seconds = about 25 minutes of continual operation. After an initial spike, the machine maintained a tight band between 94.1 deg C (201.4 F) and 94.9 deg C (202.8 F) , for the first 21 shots/15 minutes. That's really good I think, a narrow band within 0.8 deg C. Then for some reason the thermostat had a long idle time and the machine cooled off way down to 90.2 (194.4 F) for 1.5 minutes before returning to normal. It did this twice during my 25 minute experiment.
Any ideas on why a thermostat would drop off like this? Can a thermostat be half-broken? Is my experiment putting unreasonable volume thru the machine? Is there something mechanical that I need to look at?
humanoid37 Junior Member Joined: 27 Oct 2009 Posts: 3 Location: Cape Town, South Africa Expertise: I love coffee
Posted Sat Nov 7, 2009, 3:40am Subject: Re: Zaffiro way too hot - Thermostat broken?
Heck its a lonely place out here... am I the only guy left with a Zaffiro? Did they all turn bad and attack their owners on friday 13th?
Having spoken to a few knowledgeable technicians and browsed the forums further, I realise that my temperature testing method was placing too much volume through my 800ml boiler which caused the temperature spikes. When I take smaller/less frequent measurements at top & bottom of cycle I get consistentcy in a 2 deg C band.
Symbols: = New Posts since your last visit = No New Posts since last visit = Newest post
Forum Rules: No profanity, illegal acts or personal attacks will be tolerated in these discussion boards. No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum. No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum. Who Can Read The Forum? Anyone can read posts in these discussion boards. Who Can Post New Topics? Any registered CoffeeGeek member can post new topics. Who Can Post Replies? Any registered CoffeeGeek member can post replies. Can Photos be posted? Anyone can post photos in their new topics or replies. Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts. Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.
![humanoid37: Temp Test Graph.jpg](javascript:ImagePopup("/images/45712/TempTestGraph.jpg", 978, 599, "humanoid37: Temp Test Graph.jpg");)
= No New Posts since last visit 