Double set back 24volt thermostat digital

carol_3

Why your preference for Lux, guys? Here's the problem I have with Lux--lots of product problems, including very loose temperature control. I would recommend only thermostats made by the "majors," Honeywell or W-R.

Here's where the bad temp control comes from on Lux. In order to be inexpensive and "slim," instead of a mechanical relay, they use a triac. A triac is a resistor, and resistors always create heat when there's current going through them. So whenever there's a call for heating or cooling, the thermostat is making its own heat inside itself. As a result, it doesn't know what the room temp really is.

Honeywell for sure, and maybe still W-R, uses real relays. You can hear the click-click of its action. That means there's no artificial heat being created by an electronic relay, and there's tight temperature control (plus or minus one degree from setpoint).

J Resnick

Thermostat

Does anyone know of a thermostat that will replace a White Rogers double set back programable. I am looking for one that is digital It is for a hot air system 24 volts.Original White Rogers comfort set/w/ battery

frank_25

From one old man...

...to another. I would look at the Lux 511.

Empire_2

Honeywell

Say's it all. They have many to choose from.

Mike T.

carol_3

Don't listen to those guys on this one. For programmable, go for the top of the line Honeywell TH8110 touch screen stat.

jp_2

triac?

a triac is NOT a resistor, its a solid state switch!

Ron Schroeder

Triac

I believe is a resistor/diode type combination used as an electrical switch, as best as I know how to explain. So it does have smoe of the heat giving properties of the transistor.

jp_2

triac

you wouldn't want a resistor in series with a switch, of course all soild state device give off heat, and you can model this as a resistor.

but is a low power triac reallly going to heat the stat?

Ron Schroeder

Triac

not anywhere near where a true transistor would but remember it is in a confined space. If you don't beleive resistors are used in switches think about a dimmer switch, try this site and click on "the old way" "the new way" and "triacs".

http://home.howstuffworks.com/dimmer-switch.htm

jp_2

don't see where a resistor is in a traic dimmer, plus we are not talkinng about 'dimming' the furnace

so the above post suggests that short cycling is caused by the stat in this case?

I'd have to see the power draw from the furnace before I agree or disagree.

by the way, a traic is more of a bi-directional SCR. in a sense, all solid state stuff are diodes!