Heater/chiller control help.

[bkelley02]

I'm sure it's obvious to most, and I'm just not understanding the manual when I'm reading it, but I can't set the temperature control the way I'd like it.

I want to set it so the chiller comes on at 80.1 and shuts off at say 78.2, and have the heater come on at say 77.6 and shut off at 78-78.2.

Can this be done? If so, can someone please help me understand?

Thanks!

Brian

 

[badazztealcobra]

Dont worry, I have the same problems reading the instructions... Im more of a hands on kinda person, where once you show me I can do it forever...

Im hoping someone can help out since I would also like to do the same thing.

 

[AQD_ottawa]

set nominal value to 80F

two postion control

set socket to temp 1 cooling

Set socket to temp 1 heating

This will then keep your temp at around 80F steady

 

[bkelley02]

Thanks, I can get it to work like this, but I don't want the chiller coming on quite so often. That's why I was looking for the 2 degree swing. Chiller comes on at 80, shuts off at 78.2. If not, I have the chiller popping on every 45-60 minutes.

Any other way to adjust it?

 

[AQD_ottawa]

Thats fine set the hysteresis then to a value this is what it is for

page 14/40

 

[bkelley02]

OK. Please bare with me on this.

So the setting should be as follows ( I hope ).

Nominal Temp = 78.0 f

Cooling Difference = 1.8 f

Hysteresis = 0.6 f

So the Chiller should kick on at about 80.1 degrees F and shut off at about 78.3. Would this be correct?

 

[AQD_ottawa]

if you wish to be a delay in cooling then yes

 

[bkelley02]

Any other suggestions? This only pulls the temp down to 79.9.

Setting.

Nominal = 77.9

Cooling Difference = 1.8

Hysteresis = 0.48

Chiller turned on at 80.2, shut off at 79.9.

 

[AQD_ottawa]

set cooling to default and adjust the hysteresis

 

[bkelley02]

So the best I can do for chiller pull down is 1/2 of the value I set in hysteresis?

Again, I do apologize if this seems like an easy question and I should understand it quickly. I would just like to avoid having the chiller kick on so often by having it pull down such a small amount at a time before it shuts back off.

Is there no way to adjust the pull down so that it would shut off either at the nominal value or just above it from a temp about 2 degrees higher then nominal?

I've tried the cooling difference function and it does turn the chiller on at the point I want, but it only stays on and brings the temperature down half of the hysteresis value.

Hysteresis set at .6 degrees F, Nominal temp 78, chiller kicks on at 80.1 and shuts off at about 79.8. Is that really the best I can do?

Thanks again for your patience with me on this.

Brian

 

[AQD_ottawa]

You will always have a swing to a degree you are playing with tiny values of little significance and you do need to take tolerance of +/- 1 degree into account

 

[erikages]

I'm glad people are asking these questions, as this whole heater / chiller thing has driven me crazy and thus far I've kept the chiller running independently, kicking in at 79 and shutting down at 77. The Profilux controls the heater, which kicks in at 76.5 so I don't have warring heat and cooling.

Until I manage to get my hands on the PT6, which will allow stable, direct-dial temperature (so to speak) and allow me to get rid of compressor based chilling, it would be nice to have the Profilux control both chiller and heater.

The challenge for me is 1) the discussion on this thread, and 2) how to have the profilux run a chiller that has its own monitoring system. How do I bypass the on/off temp preferences of the chiller so that the profilux run it instead? As near as I can gather, you'd have to set the chiller to 75 or so, but then the Profilux would shut the power off to the chiller to switch it off, then restore power to turn the chiller on - at which point it would sit for 5 minutes or so until it ran through its start up algorithms before actually turning on.

I may just leave it jury rigged until the PT6 becomes available, as I've managed to achieve a temperature swing of 76.9 to 78.2, which is pretty good.

Erik

 

[bkelley02]

Matthias,

Do you think this is something that could be addressed in a future update? I wouldn't think that I'd be the only one that would like to be able to control the temperature in the way I described above. It would sure cut down on the amount of times the switch will be turning on and off.

Thanks,

Brian

 

[H20ENG]

I was thinking about how to control the 230V 1 hp chiller I'm using. I think I'll put a 120V Ranco controller on the chiller, then power that with the Powerbar outlet.

You guys are correct that you need a bit more hysteresis if you want a longer run time on the chiller.

 

[AQD_ottawa]

YES

 

[bkelley02]

I understand the purpose of the hysteresis to have longer run times on the chiller, but my question was more geared toward having a more constant bottom end of the temp range so that the temp wouldn't go too far below the desired temp, but there was a bit more range allowed going up. Oh well. I can work with what it can do. Built in seasonal temp swings. Never a bad thing, right?

 

[bkelley02]

Help me understand this please

Help me understand this please

I'm trying to use the hysteresis as stated in this thread and I'm still not getting the results I expected. Can someone ( yest again I know ) help me understand why this is working this way.

I have the nominal temp set at 77.9

Cooling difference 0

Hysteresis set to 1.512 degrees F.

The chiller comes on at 79.4 and shuts off at 78.6.

Would this be what I should be expecting? I had thought this would have come on closer to 78.7and shutting off closer to 78.

 

[Matthias Gross]

Hi

to be honest: I can't see the problem.

Just do this:
1. set the desired temperature
2. set the hysteresis - the higher this value the less the heater and/or chiller switches on/off
3. if you want to allow higher temperatures in your tank in order to safe energy for your chiller: increase the cooling difference

After doing these settings ProfiLux switches heaters and chillers automatically at calculated upper and lower thresholds.

If you want to have complete different independent settings for heater and chiller: create a virtual sensor and control the heater with the original sensor and the chiller with the virtual sensor

 

[Matthias Gross]

to post "Help me understand this please ":

yes, this is correct

the temperature control is special because it has to deal with 3 devices: heater, bottom heater and chiller

It must be made sure that not one of the heaters works against the chiller because we have here "overlapping hysteresis".
We explained this problem detailled in the manual, section "temperature".
If you want that your temperature comes closer to 77.9 than you should decrease the nominal temp.
Disadvantage: In the case your heater determines the temperature in cooler days it will result in a lower temperature.

 

[bkelley02]

appreciate your time to answer. Sorry for being dense. Just didn't see what I would have expected. Thank you again.