2011 Quickmill Anita heats up initially but won't maintain PID temperature

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
hi-phile

#1: Post by hi-phile »

Just recently the problem started. Machine used daily to pull shots, steam, and make an Americano.

Problem/Symptom
Once turned on it will heat up but only reach the PID Temperature setting on initial start, then it will just creep back down and show the temperature between 205 or 215. I do notice that the red heating lamp does turn on when I bypass the Hi Temp Safety switch (165c) KSD301-R, but again, the temperature will not stay at the PID setting (252). It was suggested that I replace the temperature sensor probe, and maybe the Hi Temp Safety switch.

The boiler fill does work, as once the machine has reached initial temp and I remove water from the HW wand, it will fill, but the temp won't maintain.
Also, I can see the SSR light on when it should be heating. Can pull espresso shots and they are hot, and so it seems the pressurestat is working. PID is a Delta DTB4824.

Other parts replaced previously
Float
Ulka Pump
SSR with a Crouzet
Grouphead gasket
Descale with Dezcal

Another time before had a broken connector wire where the PID was acting up showing '"no Cont"', but found that problem and corrected it.

I'm on the left coast so I cannot bring my machine to Chris' Coffee, but will contact them. Anything else I might need to check or is this fairly certain to be a temperature probe / thermocouple problem?

Giampiero

#2: Post by Giampiero »

hi-phile wrote: I do notice that the red heating lamp does turn on when I bypass the Hi Temp Safety switch
This could mean that the Hi Temp Safety Switch internal contacts are probably getting burnt and does not let pass the current properly as should, or maybe could be even an SSR malfunction, as well, maybe, a temperature probe.
Once you temporarily bypass the Hi Temp switch, does the PID shown the right temp?

hi-phile (original poster)

#3: Post by hi-phile (original poster) »

Once you temporarily bypass the Hi Temp switch, does the PID shown the right temp?
No. I wish it would/did. HTSS is bypassed, I just turned the machine on, it it took about 10 minutes to heat to 252, the heating lamp on all the way. Then, once it reached temp, I wait a few more minutes. Temp slowly starts dropping. PID light on where it shows it supposed to heat to the set temp, but it goes to 209, then the heat lamp kicks on and hear the boiler heat a little, but it stopped at 215 this time, now it's sitting at 212. It wants to heat up, higher, but no bueno.

It will intermittently start heating and it will hit 220, but then stop. Like right now, it's doing that, it went to 228 then stopped. It's maintaining lower than the PID setting. Group head is warmed up. Machine has been on for 30 minutes, temp is at 224 now.

hi-phile (original poster)

#4: Post by hi-phile (original poster) »

HTSS is bypassed. What I have to do to steam is once the machine is turned on, it hits 252, then I steam. While steaming, it will drop all the way down below 212, then no steam or hot comes out. I leave it alone, the machine will sporadically heat, I can hear the boiler and see the heat lamp come on for a few seconds. So, I pull a shot, the temperature sometimes will go up come on for a few seconds, it will reach 227 then stop heating, temp will drop down and not maintain, nor does it heat consistently like it used to and it won't go back to 252 unless the machine has been shut off for a while, but it will behave the same way.

hi-phile (original poster)

#5: Post by hi-phile (original poster) »

Okay. Just now, out of no where, machine wanted to heat up and it is now maintaining PID boiler temperature. This was after the machine was on for over an hour, but like I mentioned this is an intermittent problem, so I'm not certain if it is the temperature probe or something related to the heating circuit. So right at this moment she is behaving as she should.

Thoughts?

The float in the tank does work, once I pull out the tank or the float drops and the SSR Light turns off. The PID Out 1 light turns off too.

hi-phile (original poster)

#6: Post by hi-phile (original poster) »

Yesterday and today, the machine has been operating without any problems, but this is with the HTSS being bypassed. I am going to order a new HTSS, I believe that the scale build up probably caused the symptoms as well. Any others have similar issues or have any comments or thoughts?

Giampiero

#7: Post by Giampiero »

I don't see how scale build up can interfere with a HTSS, anyway, you seems found the solution.

hi-phile (original poster)

#8: Post by hi-phile (original poster) » replying to Giampiero »

Not, quite found a solution. The machine was working fine the past 3 days, now it's back to the intermittent heat problem. The machine's water level was just around the float so I topped it up. Temperature was around the 198-201 mark. After I topped it up, put the tank in, the heating element kicked on for about 5 seconds, went to 211 (light turned on) then stopped. Last time, this same behavior took place, heat up for a short bursts, until the heating was consistently maintained. Noticed that I can hear the heating start (boiling), but only for a very short time, not even a second and not enough for the heat lamp to turn on.

I will do some more checking, and test the heating element resistance.

Giampiero

#9: Post by Giampiero »

Maybe the magnetic floating sensor has "expired", or the power relay ( if any in that model) has some problem as well.
Try first to bypass the water reservoir sensor first, then oyu the issue persist i will try to verify the conditions of the power relay ( if any in that model).

Giampiero

#10: Post by Giampiero »