Hi, sorry for the delay, its been a hectic few days. Take at look at these 16A rated Sonof switches with temp sensor:
Its literally just power in and power out (active and neutral wires, with the earth bridged across. MAKE SURE THE EARTH IS CONTINUOUS!) in line with the feed to the heater element.
Just a quick question. On the left of the drawing I suppose it’s the main incomer, mine is already connected to the timer do I have to remove my timer and connect the sonoff? I would like the timer to be connected in the circuit and not touch it ideally.
Secondly, I have two immersion heaters in my tank and both the cables from the heaters go straight to the timer, do I need 2 sonoff switches or 1 is enough to feed both the heaters? I suppose the wiring in the timer would be different for both the heaters.
Yep, that’s the isolator on the left but you can connect to the output of the timer. If both elements are 2.75 - 3kW then you will need 2 sonof switches, but this is good because it will give you more control. The second one can be the model without a temp sensor since you only need one of them for the tank. If you want to keep the timer in circuit it would be best if it can be set permanently on or in manual override so that all control is done by the sonofs and they never lose power and drop off the network
Hi @sparkydave@BertrumUK I have received all the parts and need to attach the sensor to the heater.
I have bought 2 sensors i.e. the AM2301 and DS18B20.
I opened up the immersion heater to see where I could attach the sensor. The photo’s below are a close up view of the heater. I need your advice as to where I fit the sensor (place with a red arrow or blue arrow on the photo) and which one?
I would use the DS18B20 only. Not sure about the safety of placing where the blue arrow is as that is the heater so would try the red and see what readings you get. Usual H&S rules apply and you do this at your own risk.
The issue with putting it near the blue arrow is more a case of getting an incorrect reading of water temp. Really both locations are too close to the element but you can use a template sensor to offset the readings to account for this i guess. I would keep it away from the element simply to try and get a more accurate reading of water temp rather than element temp. Electrically, the unit is sealed (other than the terminals for the wires) so safety “shouldnt” be an issue (disclaimer: I’m not responsible for fingers going where they shouldnt!)
no, just try not to have it too close to the element as that is likely to be hotter than the water and therefore not give an accurate indication of the water temp, but like i said you can program in an offset to counter that
well you could put it in the tank as you previously mentioned as long as you have a way of doing this while keeping it all water tight. The best way to do that would be to use a thermowell. As for the offset, you will need to do this by looking at the temperature you get back from the sensor vs the actual temperature of the water, then create a template sensor.
So I got everything setup with sonoff th16 and the temp probe.
I have put the temp probe near the heater it’s doing well in terms of measuring the heat. However I find that whenever I open and close the room where my heater is because of the sonoff temp sensitivity I get temperature drops.
The temp probe is covered inside the immersion heater i.e. in the white plastic…