Jobo CPP2 not heating

[DannyTreacy]

Hi,

I have had the above machine for about years without any issues. Recently it’s stopped being so unreliable, the thermal overload switch had popped out but that was reset without issues (I presume)

I mostly use it for b&w but last time I used it for c41 about 2 weeks ago it took ages to get the temperature to respond, after twiddling the dials lots it did get to speed as normal.

Yesterday the heat settings would not respond at all, the thermal switch has stayed in. I have opened it up and the fuses all appear fine, though I’ll replace the 800ma fuse for the temperature control panel to see if this helps.

The thermal overload switch does move when pulled and pushed though it’s clearly rusty behind, is it worth putting some contact spray on this to aid it?

Any ideas appreciated!

[Greg]

I'd double check all the electrical contacts. Years ago had intermittent heating problems with a processor. All the electrical contacts visually looked to be fine, but one of them was not. Cleaned it up and the intermittent problem disappeared.

[Daniel Stone]

If you can’t seem to get it to work, pop a sous vide immersion cooker in one of the bottle slots. Cheap, easily found/sourced, and can be dedicated solely to keeping your processor at temperature :)

[DannyTreacy]

Thanks for the replies, I’ll try the first suggestion and if that doesn’t work go for the second, great tips!

Thanks.

[Duolab123]

If you run hot tap water over the thermal switch it will pop. I popped mine with maybe 125-130 F tap water. I use a toothpick or a small tool to fully depress, gently, that little breaker to get it reset. I've never fiddled with the breaker, not sure about contact cleaner. I would be gentle, maybe start by gentle cleaning with a toothpick or Qtip and a drop of alcohol (not with any added glycerin etc) I have a small bottle of ancient Kodak movie film cleaner, cfc113 and heptane. Tremendous solvent /cleaner also banned.

[DannyTreacy]

If you run hot tap water over the thermal switch it will pop. I popped mine with maybe 125-130 F tap water. I use a toothpick or a small tool to fully depress, gently, that little breaker to get it reset. I've never fiddled with the breaker, not sure about contact cleaner. I would be gentle, maybe start by gentle cleaning with a toothpick or Qtip and a drop of alcohol (not with any added glycerin etc) I have a small bottle of ancient Kodak movie film cleaner, cfc113 and heptane. Tremendous solvent /cleaner also banned.

Thanks for the information, just so I’m clear, should I remove the thermal switch from the machine before running it under a hot tap? Or does it only function if the machine is powered up? I’m hoping the former!

Thanks.

[DannyTreacy]

Just to update, I changed the fuse and put contact spray on the connectors. The thermal cutoff switch was moving freely so I left it alone. After putting it back together it is very slowly getting up to temperature but it’s really too slow, it’s taken 3 hours to rise 3*C

Does anyone know if there’s a way to speed up the heater element?!

I suppose if it maintains a temperature of say 38*C then it would be fine, just a case of mixing the water as close as possible prior to processing. It would be a pain though if I have b&w and then colour to process as I’d need to dump the 20*C temp water for fresh hotter water.

Any info on the heater would be great, thanks.

[Fred L]

I'd also take a look at the heating element and see if it might be covered in calcium. no idea if this would be a cause for really slow heating though. If you need to heat things up quickly, I'd just add hot water to the reservoir.

[Duolab123]

Just to update, I changed the fuse and put contact spray on the connectors. The thermal cutoff switch was moving freely so I left it alone. After putting it back together it is very slowly getting up to temperature but it’s really too slow, it’s taken 3 hours to rise 3*C

Does anyone know if there’s a way to speed up the heater element?!

I suppose if it maintains a temperature of say 38*C then it would be fine, just a case of mixing the water as close as possible prior to processing. It would be a pain though if I have b&w and then colour to process as I’d need to dump the 20*C temp water for fresh hotter water.

Any info on the heater would be great, thanks.

Call Omer Hecht @ CatLABS. He's official service for Jobo. There's several things that it could be. The heater connections could be dirty, the heater could be defective, etc. He takes older units on trade :rolleyes:

[DannyTreacy]

Call Omer Hecht @ CatLABS. He's official service for Jobo. There's several things that it could be. The heater connections could be dirty, the heater could be defective, etc. He takes older units on trade :rolleyes:

Thanks for the tip, I’m based in the U.K. but hopefully I could get some advice from him at least.

[Daniel Stone]

Not to sound like a siren harping the same tune, but take a look at immersion/sous-vide cooking units. They can handle what you're trying to do just fine, and can be sourced for under $100 readily online, new. I purchased a near-new Anova unit off the local classifieds for $80(half of new price) and it works fine for maintaining any temperature range I set it at. If you run a bath/shower/faucet to get water to near-temp as much as possible, then use the sous-vide for fine temp adjustment/control, it's really quite easy. So your Jobo would essentially only be acting as a circulation pump. Keep a couple frozen water bottles in the freezer to lower temperature, if needed. Re-freeze as necessary.

[Duolab123]

Not to sound like a siren harping the same tune, but take a look at immersion/sous-vide cooking units. They can handle what you're trying to do just fine, and can be sourced for under $100 readily online, new. I purchased a near-new Anova unit off the local classifieds for $80(half of new price) and it works fine for maintaining any temperature range I set it at. If you run a bath/shower/faucet to get water to near-temp as much as possible, then use the sous-vide for fine temp adjustment/control, it's really quite easy. So your Jobo would essentially only be acting as a circulation pump. Keep a couple frozen water bottles in the freezer to lower temperature, if needed. Re-freeze as necessary.

Not a bad idea. It would be handy for preheating bottles too. The sous-vide units have higher output heaters IIRC, definitely help to get the unit up to temperature faster.

[DannyTreacy]

Not to sound like a siren harping the same tune, but take a look at immersion/sous-vide cooking units. They can handle what you're trying to do just fine, and can be sourced for under $100 readily online, new. I purchased a near-new Anova unit off the local classifieds for $80(half of new price) and it works fine for maintaining any temperature range I set it at. If you run a bath/shower/faucet to get water to near-temp as much as possible, then use the sous-vide for fine temp adjustment/control, it's really quite easy. So your Jobo would essentially only be acting as a circulation pump. Keep a couple frozen water bottles in the freezer to lower temperature, if needed. Re-freeze as necessary.

Yes it’s a great suggestion and something I will definitely do if I can’t manage to fix the issue with my Jobo as it is, it would be nice to be able to fix it though, could be a long shot, the unit was made in 1984 so it’s understandable that the part has failed!

[Jimi]

Since you are in the UK, talk to Jobo in Germany directly. They were friendly and helpful when I asked a bunch of questions as to whether one could get a lift upgrade and checking if it was possible to refurbish my pretty old CPE2 unit (30 years old at least).