Sec 1000 Very Slow Response To Temp Settings

[dalpets]

I've just started to test the dual temperature controls on a SEC 1000 with my fermentation fridge.
The test involved cooling 23 litres of water in a plastic carboy using an immersibe NTC probe (not the air probe that came with the unit). This optional SS 200mm, 8.5mm diameter probe is from Ibrew & to all intents & purposes is exactly the same as the Mashmaster immersible probe that Mashmaster recommend for use with the SEC 1000, but it is out of stock with them.

Now I fully expected with this volume that their would be a degree of lag in reaching the set temperatures, particularly given the fridge had been off prior to the test. However, I was not expecting the unresponsiveness of the controller: temperature changes towards the set temperature being only 0.1*C every 15 or 20 minutes or so. This rate of change persisted for a number of hours into the test. The fridge compressor didn't seem to have any urgency to reach the set cooling temperature. With the fridge in normal operation mode (ie., without the controller) the compressor starts up with much greater urgency.

In the case of heating the 40 watt globe comes on but after waiting 45 minutes their is no change in the temperature. Given the fridge is only a medium to smaller sized fridge this is a curiosity.

The keypad on the controller is working as it should and all changes in settings that I have made have been properly saved with the power key.

This reaction of the controller does not seem right, particularly in instances when one would want responsive changes during the actual fermentation process.

Feedback from users of this controller who are also using an immersible probe would be welcome or for that matter from any one who has a technical grounding in how this digital controller should be working.

Thanks for your help.

 

[dalpets]

This topic should read STC 1000 not SEC 1000

 

[outbreak]

The controller isn't going to change the rate at which the globe heats or the fridge cools. It simply turns the fridge on when the temp goes higher than the setting and turns the globe on when it needs heat. There is lag time to the fridge turning on as there is an inbuilt lag time to stop your fridges compressor from blowing.

 

[Silo Ted]

Check your F3 setting, I think you can wind down the delay time to as little as three minutes.

 

[ekul]

Maybe check you seals on the fridge to make sure it is working efficiently, you may be losing cool somewhere. Was the fridge working before you started using it as a fermenting fridge?

The stc1000 can't effect how well your fridge cools, it just turns the fridge on and off. I reckon these things are the best ever. I've had one for 8 months without failure, and i just bought another one so i can run two fermenting fridges.

 

[Rodolphe01]

when i chill down a full fermenter from say 20 degrees to 5 degrees for conditioning, it takes hours and hours and hours.... fair bit of energy required to do it. My probe is pressed up against the side of the fermenter and insulated with a chunk of styrofoam, so in my case some points to consider:
* the fridge's original thermostat actually kills the compressor before the external controller, that is the air temperature is cold enough and the original thermostat cuts out (to try and alleviate set the fridge and freezer as cold as they go in the actual fridge, the best you can do short of disabling the thermostat somehow)
* my probe is on the outside of the fermenter, obviously it cools from the outside in, so it will take a while for the cold the penetrate, esp. when it keeps cutting out as the surface temp is at the temperature set on the controller

when you say the compressor urgency, what do you mean? it is my understanding that the compressor is either on or off, not throttled in any way.

also reduce compressor delay on the controller, but really a few minutes lag here and there won't make a huge difference, less than 1 degree in my opinion.

 

[TBird]

Just refering to my own experience here. I've got a Tempmate controller with the probe sitting in the brew (using a modified dip tube). When I first started using it I wondered why the temp wasn't dropping to the set level. It was then that I realised that the fridge thermostat was overriding the tempmate. Just turned the fridge temp control right down to maximum and no more problems.

 

[dalpets]

Thanks all for your responses.

The fridge I'm using is a vintage 1986 Fisher & Paykel which raises the question would this controller, the Brewmate STC 1000, work better with some fridges than others ie., taking into account compressor efficiency or does the controller just do its own thing anyhow.

From what everybody is saying it seems best to get the fridge to the desired temp the day before fementation so there is no lag which raises the question are there controllers available with superior rates of response comparitive to the garden variety we use for brewing. It would seem most likely that in commercial/industrial situations temp control accuracy would be mission critical, but I'm guessing such a setup would involve an investment of many thousands of dollars.

I wonder what small boutique breweries use.

 

[Silo Ted]

I wonder what small boutique breweries use.

Probably lines with glycol running through their fermentation tank (thats only a speculation)

So what is your F3 setting, dalpets? Is it set at 3 minutes? That's the tightest lag time you can set after the temp has been exceeded.

If your controller is working, and your fridge is working fine, it should make no difference how old it is. Make sure your fridge is at its lowest setting and leave it there. Maybe your fridge is set at its highest temp, not the lowest. I know with mine the 0 reading is the highest, and 7 is the lowest, which confused me at first.

 

[outbreak]

Thanks all for your responses.

The fridge I'm using is a vintage 1986 Fisher & Paykel which raises the question would this controller, the Brewmate STC 1000, work better with some fridges than others ie., taking into account compressor efficiency or does the controller just do its own thing anyhow.

From what everybody is saying it seems best to get the fridge to the desired temp the day before fementation so there is no lag which raises the question are there controllers available with superior rates of response comparitive to the garden variety we use for brewing. It would seem most likely that in commercial/industrial situations temp control accuracy would be mission critical, but I'm guessing such a setup would involve an investment of many thousands of dollars.

I wonder what small boutique breweries use.

I don't think you have listened/understood the responses. The temp controller does not have an effect on the rate of cooling, the compressor is either on or off and the temp controller is the thing that facilitates this. Even if your fridge is at temp the day before, it will still have a lag time to cool the wort down. 23l or so of wort takes a long time to cool down, and the temp fluctuations would be rather minimal seeming as it takes a long time to heat/cool this amount of wort so after you reach your desired temp the wort temp should stablise quite well. If I am off track someone please feel free to correct me.

 

[Silo Ted]

A good response from Outbreak.

Starting to think dalpets fridge is turned up too high.

Out of interest, how do others pull their temps down before pitching? No problem for me I can just whack the wort cube in a few days before, but pitching the same day as mashing, I couldn't imagine you could get a temp drop down enough with am immersion chiller unless you used ice.

 

[proudscum]

Twin immersion chillers with one in a tub with frozen pet bottles of water recycled back into my 13500 lt of rain water tanks so can run the water very quickly 15-20 min to 22-24deg c but have to watch i dont over shoot the mark.like to start the ferment at this temp but set the fridge at 19 deg c so over night the temp will be down to spot on 19.

 

[dalpets]

OK. All the controller settings are at default values. ie., difference set value=0.5*C, compressor delay time=3 minutes. The existing fridge thermostat is now set to maximum cooling. Previously it was set to minimum cooling based on other advice given on AHB, but I can see from information now provided here why maximum cooling is the correct way to go.

Everything seems to be working fine now, including the heater response at the differential temp.

Thanks again all for your help.

 

[Aus_Rider_22]

Just to clear things up for everyone, Silo Ted, you are referring to lowest as coldest?

The number thing will confuse people.

 

[Silo Ted]

yes my post made it even more confusing. For my fridge anyway, 7 is the coldest setting, and zero isnt, despite what would make sense.

dalpet, glad its working out