Controlling 2 heaters in "stages"

RicGio · 01/02/2018, 08:37 AM

I have 2 (150 watt) heaters in the basement (30 gallon) sump of my 90 gallon.
I'd like to run them in "stages" and have each heater plugged into an outlet on an EB8.

I'd like 1 heater to be "primary" with the second "stage" as a back up if 1 heater can't handle maintaining temp. I want to maintain 76F.

My current program's are:

Heater_Stg_2 (primary)
Thermometer
Heater
Fallback: OFF
Probe name : SUMP
on Temp:75.5
off Temp 77.0

Heater_Stg_1 (back up)
Thermometer
Heater
Fallback: OFF
Probe name : SUMP
on Temp:75.0
off Temp 76.5

Thought? Any other advice/suggestions? In this cold snap we are seeing currently in the North Eastern US, the primary heater has been running non stop, and hasn't needed the help of the "back up".

dentnshell · 01/07/2018, 10:06 AM

I did a similar thing with a slightly different approach. I put a delay statement in my backup heater. My thought process was that if the primary heater was taking more than allotted time ( I think I set it to 2 minutes ) to get the temperature back up then the secondary heater would kick in. Thinking about it... It would be achieving the same thing. Your statement would allow for both heaters to kick on immediately if the temperature dropped below 75. This would beneficial in both extreme cold and or a water change in which you did not have the incoming water matched correctly (emergency water changes)

radiata · 01/07/2018, 10:31 AM

I have similar code. I'm wondering lately if I should put a second thermometer probe in the system, maybe in the DT on the first floor.

01/02/2018, 08:37 AM	#1
RicGio Registered Member Join Date: Oct 2002 Location: NJ Posts: 658	Controlling 2 heaters in "stages" I have 2 (150 watt) heaters in the basement (30 gallon) sump of my 90 gallon. I'd like to run them in "stages" and have each heater plugged into an outlet on an EB8. I'd like 1 heater to be "primary" with the second "stage" as a back up if 1 heater can't handle maintaining temp. I want to maintain 76F. My current program's are: Heater_Stg_2 (primary) Thermometer Heater Fallback: OFF Probe name : SUMP on Temp:75.5 off Temp 77.0 Heater_Stg_1 (back up) Thermometer Heater Fallback: OFF Probe name : SUMP on Temp:75.0 off Temp 76.5 Thought? Any other advice/suggestions? In this cold snap we are seeing currently in the North Eastern US, the primary heater has been running non stop, and hasn't needed the help of the "back up".

01/07/2018, 10:06 AM	#2
dentnshell Registered Member Join Date: Mar 2013 Location: Oklahoma Posts: 104	I did a similar thing with a slightly different approach. I put a delay statement in my backup heater. My thought process was that if the primary heater was taking more than allotted time ( I think I set it to 2 minutes ) to get the temperature back up then the secondary heater would kick in. Thinking about it... It would be achieving the same thing. Your statement would allow for both heaters to kick on immediately if the temperature dropped below 75. This would beneficial in both extreme cold and or a water change in which you did not have the incoming water matched correctly (emergency water changes) __________________ DSA 105 Current Tank Info: DSA rimless 105

01/07/2018, 10:31 AM	#3
radiata Registered Member Join Date: Jun 2002 Location: Livingston, NJ Posts: 851	I have similar code. I'm wondering lately if I should put a second thermometer probe in the system, maybe in the DT on the first floor. __________________ "I love the smell of skimate in the morning..." Current Tank Info: Multiple - 600+ Net Gallons