Is this AC/heater combo feasible?

[38034580]

I will pack 4 wire PC fans, a PC PSU, heating resistors, an old thermostat, and cooling peltiers in one box. The heat of the peltiers and the PSU will be exhausted outside. The thermostat runs on 2 AA batteries. Here's the schematic.

[svmlegacy]

What parts are you using for the peltier and thermostat (Datasheets?)

 

5V across a 100 Ohm heater element amounts to essentially no heat. (~ 250 mW)

[38034580]

Thermostat is a Robertshaw 9615.

I will use 12V on the resistor; it gets hot.

Will the PSU generate heat when the unit is not cooling/heating? PS_ON and GND have to be permanently shorted to power the thermostat with 3V3, and when the heater/A/C turns on. it now has to power the fan with 12V and the peltier with 5V or the resistor with 12V.

[38034580]

10 hours ago, svmlegacy said:

What parts are you using for the peltier and thermostat (Datasheets?)

 

5V across a 100 Ohm heater element amounts to essentially no heat. (~ 50 mW)

Peliter: https://www.google.com/aclk?sa=l&ai=DChcSEwj_m7DJ4NPzAhVj7IYKHR6jD08YABAMGgJ2dQ&sig=AOD64_0cYe3aYBP-xIVjq3ciWcEjmONNhg&ctype=5&q=&ved=2ahUKEwihj6LJ4NPzAhVdknIEHUVgChEQ9aACegQIARBL&adurl=

[svmlegacy]

9 hours ago, 38034580 said:

Thermostat is a Robertshaw 9615.

I will use 12V on the resistor; it gets hot.

Will the PSU generate heat when the unit is not cooling/heating? PS_ON and GND have to be permanently shorted to power the thermostat with 3V3, and when the heater/A/C turns on. it now has to power the fan with 12V and the peltier with 5V or the resistor with 12V.

Using 12 V only raises the heater element to 1.44 W, enough to make the resistor warm but nowhere near enough power to be useful.

 

You'd actually be better off using the peltier as a heat pump when in heating mode, as it will generate more heating power than the heater itself.

 

The PSU will generate some heat while in use, but this varys wildly by model.

[38034580]

23 minutes ago, svmlegacy said:

Using 12 V only raises the heater element to 1.44 W, enough to make the resistor warm but nowhere near enough power to be useful.

 

You'd actually be better off using the peltier as a heat pump when in heating mode, as it will generate more heating power than the heater itself.

 

The PSU will generate some heat while in use, but this varys wildly by model.

How should I wire another peltier to the W terminal of the thermostat? Where should the "heat" peltiers face? The "cool" side of the A/C peltiers face towards the indoor fans and the hot side faces towards the exhaust pipe to go outside while in A/C mode. While in heating mode, the exhaust pipe isn't used.

[akio123008]

16 hours ago, 38034580 said:

I will pack 4 wire PC fans, a PC PSU, heating resistors, an old thermostat, and cooling peltiers in one box. The heat of the peltiers and the PSU will be exhausted outside. The thermostat runs on 2 AA batteries. Here's the schematic.

What are you heating/cooling? If it's a whole room forget about it.

[38034580]

8 hours ago, akio123008 said:

What are you heating/cooling? If it's a whole room forget about it.

Myself.