I wouldn't trust such a thing.

Mine uses the power from the ventillation system.
(Ten year old factory refurb Honeywell.)

What if you are gone and it goes berzerk because the batteries went?

A friend of mine once moved and left the house with realtor. House was
torn down because pipes burst and house was full of water for weeks
before realtor caught on.

I don't even leave power adaptors plugged in when I'm gone.

- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]

Jim Yanik wrote:

"Pete C." wrote in
ster.com:


Jim Yanik wrote:

"Pete C." wrote in
ster.com:


Jim Yanik wrote:

"Pete C." wrote in
ster.com:


Oren wrote:

On Sun, 18 Apr 2010 12:57:42 -0400, aemeijers
wrote:

mine has the programming instructions on the inside of the
TS cover.

Chuckle. yeah, mine too. But the button labels are on the
outside of the case, so you keep having to flip it over to
remember which one to punch next. Shoulda been on the inside
of the fold-down door. I'll figure it out, it is just one of
those tedious annoying things that could have been made a lot
simpler for a couple more bucks. I might even have the paper
instructions Someplace around here, but right now I haven't a
clue where.

Does the TS have a reset button?

That will set it to factory defaults I think, mine does.
(energy star suggested settings for a 5+2 type)

I never made any custom settings, so the default is fine for
me.

The whole programmable setback thing is not applicable for a lot
of folks since it presumes nobody is home during the day, which
is not the case for folks who are retired, work from home, stay
at home parents, etc.


my cheapo programmable TS works fine without any setback
programmed. Plus there's an OVERRIDE switch for when you're home.

Yes, I'm well aware of that. My point is that the idea of the
setbacks doesn't work in a lot of cases.

I think the setbacks work,it's just that the PEOPLE have a problem.
(that the setback doesn't suit their preferences)
No offense meant.

It's not preferences, it's practicalities. When people are home the
temp shouldn't be "set back".

that IS a "preference" that some people like when they go to bed.
It also saves energy when they aren't up and around.That's "practical".

Better thermostats have a 7-day program that allows setbacks during the
workweek,and none on weekends when people are home during the day,no need
to "hold" or override the setback.
Mine doesn't,it's just a cheapie.



Also with a heat pump they are even more
problematic. My TS is in hold mode all the time.


why would a heat pump work any different than my air conditioner?

They don't when in cooling mode, however they do when in heating mode.
In heating mode it is normal for them to engage backup electric heat
strips when the Tstat setpoint is raised more than two degrees. In
heat pump heating mode the efficiency is high, but the ability to
raise temps quickly is lower since the heat pump output temps are only
around 80-105 degrees, not the 150+ of electric heat (or combustion
heat).

Basically,what you're telling me is that heat pumps are
incompatible/impractical with setback thermostats.

It seems more like a design problem with the heat pump(HP) system.
If the HP is raising the temp,albeit slowly,one should be able to opt for
no electric "boost" heat. All it means is that the circulating fan runs
longer. I recognize there may be a point where the HP cannot supply enough
heat when outside temps are very low,and thus backup heat is needed.
But the system should be sized so that is a rare event.

Well, my new heat pump seems to do ok down to about 28F before it has to
kick in the aux heat, so it's not that common here in N. TX. The aux
heat with more than 2F setpoint change is a thermostat thing which seems
to be standardized.

If you have good insulation, the setback period may produce little if
any savings anyway.



When the TS says it's too warm,my AC is turned on and cools my
apartment down. The same goes for when I have 'heat' selected in the
winter.

Again, heat pumps are typically two stage devices in heating mode and
operate at different efficiencies depending on which stage is
operating. This is different from other types of heating systems.


What is "hold mode"?

Hold mode disables all setback programming and operates like a
"normal" thermostat.

Ah,on my TS,it's labelled "override".(overrides the setback)



My TS has a +/- 2 degF window;
when the room temp is within 2 degF of the setting,it is inert.
When the temp goes outside the 2 degF window,either the AC or
heat(whichever I have selected)turns on and runs until the temp is
back inside the window.

Hysteresis.


Yup.

--
Jim Yanik
jyanik
at
localnet
dot com

On Apr 19, 5:11*pm, Jim Yanik wrote:
"Pete C." wrote onster.com:

snip

They don't when in cooling mode, however they do when in heating mode.
In heating mode it is normal for them to engage backup electric heat
strips when the Tstat setpoint is raised more than two degrees. In
heat pump heating mode the efficiency is high, but the ability to
raise temps quickly is lower since the heat pump output temps are only
around 80-105 degrees, not the 150+ of electric heat (or combustion
heat).

Basically,what you're telling me is that heat pumps are
incompatible/impractical with setback thermostats.

Pretty much what I've found with mine. AFAIK, they're not recommended.

It seems more like a design problem with the heat pump(HP) system.
If the HP is raising the temp,albeit slowly,one should be able to opt for
no electric "boost" heat. All it means is that the circulating fan runs
longer. I recognize there may be a point where the HP cannot supply enough
heat when outside temps are very low,and thus backup heat is needed.
But the system should be sized so that is a rare event.

If it takes three or four hours to recover, there's hardly a point
setting the temperature back.

...

On Apr 17, 11:25*pm, aemeijers wrote:
Given that power is available from the furnace, why do these things need
more than a button cell for memory backup, anyway?

Because it's CHEAPER to put in a battery box than it is to design
electronics to run off the 24VAC from the furnace.