Digital thermostat

[Eric Williams]

Can anyone please recommend one of the above units. I really need something that is efficient at the lower end of the temp. spectrum rather than the higher temps. ( if available) I can only afford to keep my plants at around 6-8C. I also read that to enable the thermostat to work I need to short out the analogue bi metal strip on the heater or set it at a very low setting. Any advice on this would be very helpful. My heater is a 1-2 kw job. Thanks

[habanerocat]

Most people on here including myself use a BioGreen or an InkBird. Both are accurate at lower temperatures to about 1 deg C.

If I'm reading the specs right the standard units are rated as follows:

InkBird ITC-308 is rated at 2Kw or about 10 Amps.

https://www.ink-bird.com/products-tempe ... tc308.html

BioGreen Ter2 is rated at 3Kw or about 16 Amps.

https://biogreen.world/en/catalog/produ ... o2digital/

So if you want to switch the full 2Kw directly you'd probably be better off with the BioGreen.

Once you have the heater itself turned down to it's lowest temperature setting it will be turned on and off by the temperature controller. No need to modify the heater. I wouldn't go messing with it anyway as most heaters have over temperature protection and you might short out the wrong thing.

[el48tel]

I agree. The InkBird is an excellent piece of kit. I'd be less likely to reccomend using the built in thermostat in any heater or blower since it would be less accurate, and you really need the thermostat probe to be away from the heater ... in the position you choose. You will get a temperature gradient across the GH and you will get pockets of still air where the air flow doesn't reach. The probe should be at the coolest part of the GH. Some folk run a separate continuous non heating fan in addition to any heating to minimize the temperature gradient and cold spots.

[Jim_Mercer]

Once you have the heater itself turned down to it's lowest temperature setting it will be turned on and off by the temperature controller. No need to modify the heater. I wouldn't go messing with it anyway as most heaters have over temperature protection and you might short out the wrong thing.

If heater is on low setting its thermostat will overrule your digital thermostat, the heater thermostat needs to be high then the digital thermostat is in control

[habanerocat]

Once you have the heater itself turned down to it's lowest temperature setting it will be turned on and off by the temperature controller. No need to modify the heater. I wouldn't go messing with it anyway as most heaters have over temperature protection and you might short out the wrong thing.

If heater is on low setting its thermostat will overrule your digital thermostat, the heater thermostat needs to be high then the digital thermostat is in control

Correct of course. I must stop posting at 1am.......

[Stuart]

The specs for the inkbird model seem to vary depending on where I look. Some show max output 1100w and some show 2200w. Are there different models or different models for different countries, max output of 1100watts wouldn't be much use.

Stuart

[FredG]

It's 1100w @ 110V and 2200W @ 220V

[el48tel]

Remember ..... if your heater draws more than 2200W ..... it will overload the InkBird.

[Eric Williams]

Thanks all, that's the one I had my eye on too. Re original thermostat on heater I am confused. I always thought when it was set it would close when temps reached the set value ? If I set it at a high value in Wnter it will remain open and the digital one cannot switch on heater. Perhaps my thinking is dimmed by old age lol. Cheers

[ragamala]

Eric, as you've already confirmed your heater is a 1 / 2 kw model I too have no hesitation in recommending the Inkbird. I have used both this (ITC-308 I think) and BioGreen Themo 2 for some years now. Both do the job well, but the Inkbird is more flexible and has more capability - i.e. better spec other than kw capacity than the BioGreen. I think this has been covered in more detail in previous threads from a couple of years ago. And another significant advantage, it is cheaper.

Re the heater internal thermostat. For winter use, i.e. heating, you need to set the heater "always on" - in other words the heater functions whenever current (totally contolled by the Inkbird) is passed through to it. This means you set the internal thermostat to its highest level, so the heater thermostat is conned into thinking it is never hot enough.

For summer cooling, which means changing the heater switch to fan only, and of course setting the external thermostat accordingly, you need to fool the heater into thinking it is always too hot, so in this situation whenever the external thermostat provides power the fan switches on. That means in summer setting the internal thermostat to its lowest value, i.e. the heater thinks it is always hotter than it really is so switches on the cooling fan

Hope that makes sense..