Heater and Chiller question

[Sebyte]

I would like to get an opinion on the physical settings for the tank heater and chiller, I am still in the setting up phase.

For example, in RA I have set my Heater set to come on at 78f and go off at 79f, and the chiller to come on at 81f and go off at 79.5f. I have the 0.5f difference to allow for hysteresis and prevent an instant on off loop. Well that is my theory

First question: is the 0.5f going to be enough to prevent an instant on off loop.

Second, is it better to have the Heaters internal thermostat set high or at the same as the temperature setting in RA, and the chiller internal program temperature set below the RA settings. I don't want the chiller to shut down before it has reached the RA setting.

Any comments by other users on their settings would be of interest.

[wolfador]

Does it get that hot in Toronto that you need a chiller? lol

It is going to be hard to say exactly what temps to set at without them actually being on the tank. Depending on what you are keeping in the tank most are okay within a range as long as the temp does not fluctuate much. I found it alot easier to keep my tank at 78 instead of 80. When I tried to keep the tank at 80 the heater was almost always running.

[Sebyte]

I live in a south facing cond, with a wall of glass, and yes belive it or not in the summer the room would be over 100f if not for the aircon. Also my tank is a fully enclosed Red sea Max 250, which are notorious for running hot. Because the sump is integral on the back, the skimmer alone could keep the tank at temperature. There is 250w of HO T5 lighting which is the real problem. So my next project is building an LED system. The tank has been running for over two years and so far I have kept the average temperature to 80.

The question was more around if the heater internal thermostat should be set higher than th RA setting, and chiller lower, if you see what I mean. Also I don't want to have the heater switching off and the chiller coming right on!

Now for the plug, Southern Ontario has fantastic summers and not such bad winters! Try a vacation

[rimai]

I think you should use slightly higher on the heater than what you set on RA and slightly lower on the chiller than you set on RA.
But, you would not get on/off loop, because in your case, heater turns on only at 78 and chiller turns on at 81. So you really have 3 degree difference .

[Sebyte]

Ok, until I try this live I will not know how stable the Temp1 probe will be, and I may lower the cut in temperature for the chiller. It is good that I will be able to fine tune the temperature control from the RA client.

All being well I will go live tomorrow, just need to rearrange the electrical feeds to the T5 ballasts in the hood. Red Sea do a good job on the finish of the hood etc, but make it difficult to get into the works,