DIY HUMIDISTAT(humidify/dehumidify) THERMOSTAT(heat/cool)

DIY ENVIRONMENTAL CONTROLS

alright i am about to put these together and provide the steps to do so.

Thermostat:
first off we need to decide what we are going to control, in my case in order to raise the heat i am going to be using a 120vac space heater...

and to cool it i will be using a typical 120vac fan...

and i need to chose a controller, a 24vac thermostat...

and last and most important i need a 24vac controlled 120vac switch aka a SPDT relay....


Humidistat:
for this we will need a similar list,
first a cheapo 120vac humidifier...

next we need a 120vac dehumidifier...

and for the 24v humidistat controller...

and like before we need a 24v controlled 120vac SPDT relay...

I am in the process of grabbing the rest of the materials and will complete this tutorial within a couple days...

ALSO...if you are aware of lower priced items that are similar to the ones listed please make a note...
thanks

Subscribed looking forward to seeing this all put together nice project man good luck

...UPDATE...

ok i'm going to start addressing the wiring for the relay that will allow the heater(2) to come on when the thermostat(1)(3) closes the circuit signaling the device to turn on, and when the wanted temperature is reached by the thermostat(1)(3) will open and cause the switch to be thrown from the heater(2) to the fan(5) which will keep the room cooled to the wanted temperature...now you might be asking yourself what is (4) doing in the circuit, well it is the COMMON coming from your house's power.

if this is confusing please feel free to ask questions i will continue to update as i finish different parts.
thanks

thermostat wiring....

ok this is pretty basic and oddly enough you have options here...
first off if you are using the thermostat unit above u might note that it actually has 3 points of contact but we will ignore the one in the middle because it is just a power supply option we will address later....
back to whats in the picture though, basically you connect (1) from the relay to (t1) on the thermostat and also connect (3) from the relay to (t2) on the thermostat.
note: (1) and (3) are interchangeable in our situation, meaning you can also hook (t1)-(3) and (t2)-1, but its not a big deal.
thanks

alright a little further into the wiring....
make note with all of your units(heater,fan,de/humidifier) take the plug end and look at the prongs...notice how one is bigger than the other and same with the wall outlet...

this is going to be useful to note somehow, ie making tape labels...
by the way a little info for the next part of the thread, the white will always be connected from the units to your houses power the black will be the side in the circuit that will be getting switched on and off
thanks

does anyone want me to go on further with this or is the rest self explanatory?
thanks

Thanks for the information.

This is new to me so I'm curious, the number 5 connection does not look like there's much to grab onto? how to wire from the SPDT relay to the other devices? the themostat generates/supplies the 24 volts? the thermostat is hardwired to the 110 house voltage?

Looking forward to the rest of your lessons!

good observation, the picture above is actually the SPST version of the relay but the location of (5) is where its at on the SPDT version.
the way this circuit works is that the actual 24vac thermostat is powered by either batteries or a 24vac power adapter.
the power for the devices comes in through terminal (4).
to give a basic idea of how it works is like this...
say you want to keep the room at 80F and the current temp is at 75F well the circuit by default is running the fan to cool but since the probe detects the ambient air is 5 degrees too cold it closes the circuit which causes the relay to flip the power from (4)(5) and now creates the closed circuit of (4)(2) which turns off the fan and starts the heater up, as the temp raises to 80F the circuit reopens and the fan comes back on.
let me know if that makes sense

also for a picture of the SPDT relay look here http://www.white-rodgers.com/wrdhom/pdfs/06_Cat_pages/Cat_06_pg0114.pdf
thanks

Yes! You're making sense! Thanks for the quick reply and the SPDT pdf link. I understand now the thermostat is powered by batteries or a 24vac power adapter (a transformer 110v/24v like for a doorbell ringer).

#2, 4 & 5 posts are all 110 volt connections with #4 being the hot wire, correct? Either way the relay flips, a closed connection is made. either a 4/5 closed connection or a 4/2 closed connection is made.

In your future lessons I guess you'll be showing/discussing details on the wiring necessary on how to best connect the relay to the 110 devices (fans, heaters, etc.) ?

Thanks

QS

This is interesting and I was dreading making my own high voltage switch board.

subscribed and +rep
can't wait to make my own

...UpdatE...
i am currently waiting on a few of the items to arrive this should all be wrapped up by 3 days.
thanks

...just thought i should say that the thermostat i'm using is a heat only and the humidistat is humidify only that is why i used a single-pole double-throw in each unit so that when the thermo. and humidistat show that the temp/humidity is above the set amount on the controllers(thermostat/humidistat) the spdt opens up and turns the fan/dehumidifier on respectivley.

with that being said if you have a thermo that is cool only or a humidistat that is dehumidify only, the same setup i have will work, only modification is to swith the (5) and (2) terminals.

and lastly if you end up having the top-o-line thermostat that comes with heat and cooling settings or if the humidistat you buy comes with humidify and dehumidify settings this can still be done, the only difference in the setup and mine is that instead of using SPDT switches you would use 2 Single-PoleSingle-Throw/normally-open switches for each unit, or possibly a DoublePoleDoubleThrow for each unit, i have to check on the DPDT though.

also, these will work for the 220vac folks also, if anyone is in this situation let me know and i will explain the correct relay switch to get.
*edit note: i just realized that the relays i'm using already are set up to handle the Euro/220vac.
thanks

Glad you're sticking with it. Great info.

..update...
while getting bored i designed a very cheap dehumidifier for the environment controller and will be completing it tomorrow.
here's the link https://www.rollitup.org/do-yourself/144020-diy-dehumidifier.html

update...
sorry for being away for so long this project is soon to be on the road,
some changes have been made though, i will be making the humidistat by the method described above but the thermostat has been changed.
i found a more extensive method for making the thermostat, heres the link to the one i will be making,
http://www.unusualelectronics.co.uk/projects/proj2.php
the parts have been ordered and are shown to be delivered tomorrow or by monday the latest, i have already recieved the SPDT relays though.

p.s. don't be scared by the new thermostat i will provide a step-by-step tutorial with pictures, maybe even a video.
let me know which would be easier to follow along with.
thanks

instead of using SPDT switches you would use 2 Single-PoleSingle-Throw/normally-open switches for each unit, or possibly a DoublePoleDoubleThrow for each unit???

is that a question or a suggestion? the pole and throw arrangement are dependent on which style of thermo/humidistat controller you have available,
now say your scenario is like this, you have a both controllers with 24vac control and the environment units are all 120/240vac you could use a DPDT

it1sasecret said:

is that a question or a suggestion? the pole and throw arrangement are dependent on which style of thermo/humidistat controller you have available,
now say your scenario is like this, you have a both controllers with 24vac control and the environment units are all 120/240vac you could use a DPDT

Click to expand...

was a question,but then i deleted half of the post after googling it,

i got 240v thermostat that comes with heat and cooling and 240v environment units so theres no need for dpdt or relays or anything..........is that right?

well lets see, your heating and cooling unit is 240v, does it have sockets to plug in appliances or are you saying it runs off 240? if the case is the latter than you have a couple options, the simplest which is NOT recommended is to wire up the contacts from the thermo to have sockets the reason this is NOT recommended is because the thermostats aren't wired to have that many amps going through the circuitry, your best bet would be to get 2 of these
http://www.grainger.com/Grainger/items/4E942
it is a SPDT also, you could use 2 SPST's if you can find them with the correct ratings, and you could even use a DPDT with the correct ratings
the reason i recommend the SPDT above is only because thats the cheapest relay with the correct ratings i could find on grainger.com
what you're looking for in your case is a relay with a primary rating of 240vac and a secondary of 240vac.
there also is another option but i can't remember the correct name of the units i think they're called "something i can't remember" contacts