Heating and Cooling Control
I detailed the cooling system itself in a different post
And of course everything we read is true.....so that's one amazing pump, lol.
www.reef2reef.com
For heaters, I've selected Finnex titanium heaters. Thank you to those who have recommended them. For now, I've ordered one 500 watt and one 800 watt. They arrive today. Heating is a significant need much of the year since the basement where much of the system is stays pretty cool year round. I do not know if these will be enough in winter, but I'll wait and see, ordering more as needed. Outside temps can get below zero F here on occasions.
The 800 watt may be seasonal, being removed in summer and any shoulder season where it's not needed. Not having it in place just removes a possible failure point. A bonus of the Finnex heaters is that they act as a grounding probe for water they are in contact with, helping ensure that if a device leaks actual current, it will trip a GFCI (more on that setup later as I plan to use many GFCI) rather than waiting for me to reach into to the sump to complete the circuit in bare feet on the basement floor.
Control of both heating and cooling will fall to a multiple inkbird plan. I've gotten what I think are very good prices for these on sale lately with coupons, and I'm awaiting getting a couple more when the price is right.
The inkbird 308 wifi can control both heaters and cooling, and tells me the temp over wifi for remote monitoring. I've already connected both to the app and they report just fine, although setup was, as is often the case with these sorts of things, somewhat frustrating. I actually came back to one this morning to try again, and found it somehow finished connecting on its own despite telling me it failed to pair. lol
I got them for about $35 each. Cooling control will use two of these for extra protection. While there are some details about the gap between cooling on and cooling off that I'll need to work out in practice, I expect I will set that to the minimum (1 deg F) with no cooling delay since the solenoid has no issue turning on and off rapidly.
In summary, one will be set to, say, a setting of 79 deg F, and cool (open the cooling solenoid) only if the tank water gets above that point. The solenoid will be plugged into the cooling outlet on that inkbird
That inkbird will be directly plugged into the cooling outlet of a second, identical inkbird. That second inkbird will only power the cooling outlet if the temperature is above its setpoint of, say, 75 deg F. It is the backup shut off if the first cooling inkbird fails to control properly somehow. It doesn't help a failed off, but it will prevent a failed on, which is the much bigger concern in my opinion.
In this fashion, the cooling solenoid will only get power if both inkbirds think cooling is needed. In a perfect world, the second one will always power the first one, and the first one will do all of on off control.
I just ordered a third inkbird 308, but not the wif fi version since it was on sale for only $24. I'd prefer more temp monitoring over wi fi, but I already have at least 2 (the two wifi 308 inkbirds), and maybe more depending on what other devices I get.
This third inkbird will be used for a heating control, in a fashion similar to the cooling control. I'll need another one or two inkbirds for heating control (one cannot control both the 500w and 800 w Finnex due to current draw), but what exactly I get will depend on Amazon sales in the future. One inkbird will be the failsafe shut off and the second one plugged into it will be the primary on off controller.
One very important aspect that I want to mention. I think it is very important that the temperature measurement for the control be in the same chamber as the actual heating or cooling device. If the return pump stops for any reason (except a power failure), and the sensor is in a different sump chamber, the temp controls may continually think more heating or cooling is needed, potentially driving the temps way up or down in that chamber. It's a drawback of a titanium heater without its own temp sensor, and a drawback of my cooling system, but if the two active sensors are in the same chamber, the issue is largely eliminated.
Any comments or concerns about this setup are appreciated. :)