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HVAC control wiring...

D

Don Y

Guest
On 8/10/2020 6:00 PM, Michael Terrell wrote:
(You can buy METAL Jboxes that support the installation of barriers. You
just don\'t find them at your local retail/industry outlet)

Whatever. These work, and are great for an office, or behind a TV or home
computer.
Plastic boxes are often small volume. So, fitting a dimmer (with 3 or 4
pigtails -- and wirenuts -- in addition to the device) is often a squeeze.
Too often, I see folks try to \"pull\" the device into the box by letting the
mounting screws drag it in. This doesn\'t fare well for the plastic -- once
\"stripped\", you\'re stuck!

I\'ve also found many DIYers who\'ve miswired something that the UNGROUNDED
plastic box didn\'t \"complain\" about. E.g., when we moved into THIS place,
some dolt had replaced a three-way switch in the garage with a regular
switch. Wondering what to do with the third wire (traveller), he opted to
tie it to the ground screw on the switch (three wires, three screws, right?)

So, depending on the position of the other 3-way on that circuit, the \"frame\"
of the switch would be at mains potential -- or not.

Had the box been metal -- earthed -- the first time power was reapplied
and that traveller energized would have blown the breaker (hard short
between line and earth).

I found another case where a guy wired a 220V air conditioner (window
unit) similarly.

<shakes head>

I also don\'t like \"open back\" installations. I want the box to define the
extents of the wire\'s domain; not have just a \"hole into the wall space\".
E.g., all of my network, phone and CATV drops terminate in (metal) Jboxes.

Not all metal boxes are great. Some are flimsy, and others are
less than an inch deep.
Yes. But, you can select the box (construction and volume) to fit your
needs. E.g., I used 4x4x2.25 boxes for all the single device Jboxes, here.
If I need a 2G box, I move up to 4-11/16. No issues trying to cram wires
into a barely large enough box (e.g., you can use 4\" sq for 2 devices but
it\'s much tighter).

I had to rewire my girlfriend\'s family home, back in
the \'60s. All of the boxes on exterior walls used those. Their furnace
failed while they were at a Christmas party. The damage was the worst around
the furnace, but the smoke and water damaged the entire house. All the
drywall had to be removed, along with the insulation. Since the block home
was stripped to bare suds, they decided to replace all of the wiring. Some
early Romex hardened and cracked fro the heat in the attic, and along the
exterior walls. It took a lot of work. I would ride her school bus after
school and work with them until 9:00 PM, then my dad would pick me up. I
would do my homework, and get what sleep that I could. It was a true labor
of love. It was our Junior year of high school. Sadly, she passed away at
48, 20 years ago.
Sorry to hear that. I lost a couple of friends in their teens (same age).
It was \"scary\", for want of a better word. (when you\'re that age, you
associate death with \"grandparents\", not your peers!)
 
R

Ricketty C

Guest
On Monday, August 10, 2020 at 9:38:10 PM UTC-4, Don Y wrote:
On 8/10/2020 6:00 PM, Michael Terrell wrote:
(You can buy METAL Jboxes that support the installation of barriers. You
just don\'t find them at your local retail/industry outlet)

Whatever. These work, and are great for an office, or behind a TV or home
computer.

Plastic boxes are often small volume. So, fitting a dimmer (with 3 or 4
pigtails -- and wirenuts -- in addition to the device) is often a squeeze..
Too often, I see folks try to \"pull\" the device into the box by letting the
mounting screws drag it in. This doesn\'t fare well for the plastic -- once
\"stripped\", you\'re stuck!

I\'ve also found many DIYers who\'ve miswired something that the UNGROUNDED
plastic box didn\'t \"complain\" about. E.g., when we moved into THIS place,
some dolt had replaced a three-way switch in the garage with a regular
switch. Wondering what to do with the third wire (traveller), he opted to
tie it to the ground screw on the switch (three wires, three screws, right?)

So, depending on the position of the other 3-way on that circuit, the \"frame\"
of the switch would be at mains potential -- or not.

Had the box been metal -- earthed -- the first time power was reapplied
and that traveller energized would have blown the breaker (hard short
between line and earth).
Something is wrong with your description. If he tied the extra wire to the ground screw, that should have created the same short as if it had been in a metal box. Wasn\'t the ground wire tied to the ground screw? In fact, I believe code says the two wires can\'t both be on the same screw, so they would have been pigtailed together with a third wire which would be tied to the screw.

So what are you not telling us? Was the ground wire cut off? In any event this has nothing to do with plastic boxes.


I found another case where a guy wired a 220V air conditioner (window
unit) similarly.

shakes head

I also don\'t like \"open back\" installations. I want the box to define the
extents of the wire\'s domain; not have just a \"hole into the wall space\".
E.g., all of my network, phone and CATV drops terminate in (metal) Jboxes..
The open back is only for the low voltage wires.

--

Rick C.

+ Get 1,000 miles of free Supercharging
+ Tesla referral code - https://ts.la/richard11209
 
G

Grant Taylor

Guest
On 8/10/20 5:17 PM, Don Y wrote:
They\'re plastic. Ick, ick, ick. (I replaced all of the plastic
Jboxes with new-work metal boxes, here. More cubic inches as well
as more durable when removing/reinstalling devices).
I\'ve seen plenty of plastic boxes that have more room than many metal
boxes; gang for gang count.

And, you can\'t get the low voltage compartment to be \"the center of
a 3G\" or \"second in from the left in a 4G\", or \"two ends of a 3G\", etc.
Why not?

Why can\'t you run a short piece of Romex (with full insulation) out the
back of one end of the box and in to the other end of the box?

(You can buy METAL Jboxes that support the installation of barriers.
You just don\'t find them at your local retail/industry outlet)
Wouldn\'t the metal 3+ gang junction boxes suffer from the same problem
you\'re describing above? If not, why not?



--
Grant. . . .
unix || die
 
D

Don Y

Guest
On 8/10/2020 10:01 PM, Grant Taylor wrote:
On 8/10/20 5:17 PM, Don Y wrote:
They\'re plastic. Ick, ick, ick. (I replaced all of the plastic Jboxes with
new-work metal boxes, here. More cubic inches as well as more durable when
removing/reinstalling devices).

I\'ve seen plenty of plastic boxes that have more room than many metal boxes;
gang for gang count.
You can cherry pick examples of each. But, in general, you can find more
volume units in metal boxes than plastic. My 1G boxes are 34.3 cu in;
2G boxes are 51 cu in. The typical 1G NM box is maybe 24 -- and uses the
entire depth of the wall to accomplish that (i.e., can\'t put anything
behind it; I can slip a 1.5\" box behind mine -- or a framing member!).

And, you can\'t get the low voltage compartment to be \"the center of a 3G\" or
\"second in from the left in a 4G\", or \"two ends of a 3G\", etc.

Why not?

Why can\'t you run a short piece of Romex (with full insulation) out the back of
one end of the box and in to the other end of the box?
Of course you can run conductors outside the box -- assuming there are
points where you can enter into each device slot (\"gang\"). But remember,
that\'s another set of conductors in at least one of those \"gangs\". Most
plastic boxes don\'t have extra room \"off to the side\" to stash wire and
wirenuts.

But, you need a \"generic\" box that is capable of accepting barrier *inserts*.
A \"dual voltage\" box that treats the low voltage portion as \"open backed\"
implicitly constrains where the low voltage portion of the box must reside.
E.g., in Michael\'s example, it must adjoin the stud to which the box is
mounted because the \"near\" gang is the only one that is fully enclosed.

(Yes, you can flip it upside down to have the low voltage portion on the
right vs. left of the high voltage. But, you also have to move to the
opposite side of the mounting stud to do so -- the centerline of your
box has now shifted ~6 inches!)

(You can buy METAL Jboxes that support the installation of barriers. You just
don\'t find them at your local retail/industry outlet)

Wouldn\'t the metal 3+ gang junction boxes suffer from the same problem you\'re
describing above? If not, why not?
Because the barrier is a separate piece of metal that is installed in the box.

If you want to subdivide a 4G box into lo/hi/lo/hi you simply install three
barriers.

If you want to subdivide a 3G box into hi/lo/hi *or* lo/hi/lo, you install 2
barriers. Or, lo-lo/hi, lo/hi-hi, hi-hi/lo, etc. with just one.

There\'s no difference between a low voltage and high voltage \"compartment\"
(unlike Michael\'s example).

Here\'s a 3G metal box. Note the slots cut in the top/bottom/back for the
introduction of barrier plates. (we have lots of 3G and 4G boxes, here)

<https://www.garvinindustries.com/media/catalog/product/cache/1/image/1200x1200/9df78eab33525d08d6e5fb8d27136e95/g/b/gb-2123.jpg>

<https://www.garvinindustries.com/media/catalog/product/cache/1/image/400x400/9df78eab33525d08d6e5fb8d27136e95/g/b/gbp-21212.jpg>

The (metal) barriers are usually made to address boxes of differing depths.
You snap off the excess portion of the barrier (in much the same way you
knock-out an opening for a cable clamp) to account for the depth of the
mudring. The mudring\'s presence prevents the divider from being removed
after installation.

You can buy plastic Jboxes that will similarly accept the introduction of
a plastic barrier -- there are \"slots\" in the edges of the box into which
the barrier is placed. (note that the Code requires the barrier to be
permanent so you have to adhere the plastic barrier in place. otherwise,
removing the wall plate would allow you to slide the barrier out of its slot)

And, when you\'re done, you\'re still stuck with a plastic box! I\'m tired of
finding wood/sheet-metal screws used in place of the proper device mounting
screws just because the \"hole wore out\" (and no one wanted to replace the box
to fix it!) And gaps around the boxes where they aren\'t snug fit to the
drywall (heat loss).

[We replaced all of the devices, here, when we moved in -- she didn\'t like
\"ivory\" and wanted \"white\" -- and all the receptacles were upside down. Then,
replaced them, again, to move to rocker style from toggle. Then, again, to add
dimmers. Some saw replacement to deal with flimsy plastic rocker components.
And, again, to retrofit with \"LED dimmers\". We\'ll replace them, yet again,
when I retrofit with \"smart\" switches. The metal mudrings have no problem
seeing this much \"screwing\" activity -- as long as you don\'t crossthread. :> ]
 
A

amdx

Guest
On 8/3/2020 2:11 PM, John Larkin wrote:
On Mon, 3 Aug 2020 09:20:42 -0700, Don Y <blockedofcourse@foo.invalid
wrote:

In the US, HVAC systems are controlled via low-voltage wiring
(to the \"thermostat\").

In most homes that I\'ve seen, this is just \"bell wire\" run
through the wall interior exiting through an /ad hoc/ hole
to connect to the thermostat from the rear.

Has anyone encountered a Jbox in this location (devoid
of mains voltage)?
I\'ve never see a box for thermostat wiring.

In our cabin, I have a secret relay that parallels the thermostat, to
force the heat on remotely. More ad-hoc wiring!
I had that for years, but I had a button that I could push and make the
air conditioner come on for

2-1/2 minutes or switchable to 3-1/2 minutes. In the winter I moved a
clip lead to a different connection

and could do the same for heat. I used a latching relay, fet and a
timing capacitor with a resistor.

  When I got a new furnace installed with a new thermostat, the new
thermostat has at least twice

as many wires and never took the time to learn which wires to hook my
circuit to.

  The new air conditioner did a better job with humidity, so it doesn\'t
seem as important at it did.

Although I just looked and it\'s 78*F with 48% humidity. I\'d prefer
around 40%. This is my own fault, I went

for a walk and apparently didn\'t pull the door tight, when I got home, I
noticed the door cracked open 10 inches.

I grabbed a knife with a foot long blade and toured the house. I didn\'t
have to hurt anyone :)

 We do keep it at 78*F, after a few years of this, I feel chilly at
77*F, as long as the humidity is around 40%!

Mikek



--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
 
G

Grant Taylor

Guest
On 8/11/20 10:52 AM, amdx wrote:
I had that for years, but I had a button that I could push and make
the air conditioner come on for 2-1/2 minutes or switchable to 3-1/2
minutes. In the winter I moved a clip lead to a different connection
and could do the same for heat. I used a latching relay, fet and a
timing capacitor with a resistor.
I have often wanted a \"boost\" feature that would run the furnace / A.C.
(which ever mode it\'s in) for 5 / 10 / 15 minutes (whatever the feature
supported).

This seems like it should be a relatively simple feature to add to
thermostats.



--
Grant. . . .
unix || die
 
D

Don Y

Guest
On 8/11/2020 9:31 PM, Grant Taylor wrote:
On 8/11/20 10:52 AM, amdx wrote:
I had that for years, but I had a button that I could push and make the air
conditioner come on for 2-1/2 minutes or switchable to 3-1/2 minutes. In the
winter I moved a clip lead to a different connection and could do the same
for heat. I used a latching relay, fet and a timing capacitor with a resistor.

I have often wanted a \"boost\" feature that would run the furnace / A.C. (which
ever mode it\'s in) for 5 / 10 / 15 minutes (whatever the feature supported).
Why express it in units of minutes-run-time instead of (fractional) degrees?
We have a \"temporary override\" that lets us tweek the setpoint, in the short
term, before returning to \"normal\", thereafter.

> This seems like it should be a relatively simple feature to add to thermostats.

I added a \"recirculate\" feature that ensures the blower runs for some number
of minutes out of some interval. Often, we have no demand for heating/cooling
for large stretches of time (cooling overnite; heating during daylight). This
gives the interior air a bit of a \"refresher\", even if the plant isn\'t doing
anything.
 
G

Grant Taylor

Guest
On 8/11/20 10:47 PM, Don Y wrote:
Why express it in units of minutes-run-time instead of (fractional)
degrees? We have a \"temporary override\" that lets us tweek the
setpoint, in the short term, before returning to \"normal\", thereafter.
Have you ever gotten up on a cold morning, or come in the house on a
particularly hot afternoon and just wanted the heat / air to run for X
number of minutes, independent of what it did to the temperature? I
know that I have.

I also have heard many friends tell me stories of temporarily turning
the thermostat significantly warmer or cooler so that it unit will kick
on and run. Later they go back and reset the temperature back to what
it\'s set point was.

Think about it like the heat lamp timers that you occasionally see in
bathrooms. Just run for X number of minutes.

I added a \"recirculate\" feature that ensures the blower runs for some
number of minutes out of some interval. Often, we have no demand
for heating/cooling for large stretches of time (cooling overnite;
heating during daylight). This gives the interior air a bit of a
\"refresher\", even if the plant isn\'t doing anything.
Yep. I\'ve told my wife that I want our next furnace to have the ability
to run the fan, preferably variable speed, independently of the heating
/ cooling function. Circulation is very nice.



--
Grant. . . .
unix || die
 
D

Don Y

Guest
On 8/11/2020 10:58 PM, Grant Taylor wrote:
On 8/11/20 10:47 PM, Don Y wrote:
Why express it in units of minutes-run-time instead of (fractional) degrees?
We have a \"temporary override\" that lets us tweek the setpoint, in the short
term, before returning to \"normal\", thereafter.

Have you ever gotten up on a cold morning, or come in the house on a
particularly hot afternoon and just wanted the heat / air to run for X number
of minutes, independent of what it did to the temperature? I know that I have.
Yes, but we tell it to adjust the temperature to do so. This is just a
*temporary* change to the setpoint; once it is attained, the old setpoint is
restored (so you don\'t have to remember that you\'ve CHANGED the setpoint).

We can change the setpoint \"permanently\" (like a HOLD function) or a
few different \"temporary\" ways. E.g., my other half turns the ACbrrr
off while showering so she doesn\'t freeze when she leaves the shower
and happens to step into the cold air \"coincidentally\" blowing into the
bathroom. Later, the setpoint is automatically restored (in case she
fails to manually release the override)

I also have heard many friends tell me stories of temporarily turning the
thermostat significantly warmer or cooler so that it unit will kick on and
run. Later they go back and reset the temperature back to what it\'s set point
was.

Think about it like the heat lamp timers that you occasionally see in
bathrooms. Just run for X number of minutes.
But there\'s no other sensible criteria for a heat lamp other than time.
You\'re not using it to change the temperature of the room. Or, \"cook food\".

It boils down to \"how long do you plan on it taking you to dry off and
exit the room?\"

I added a \"recirculate\" feature that ensures the blower runs for some number
of minutes out of some interval. Often, we have no demand for
heating/cooling for large stretches of time (cooling overnite; heating during
daylight). This gives the interior air a bit of a \"refresher\", even if the
plant isn\'t doing anything.

Yep. I\'ve told my wife that I want our next furnace to have the ability to run
the fan, preferably variable speed, independently of the heating / cooling
function. Circulation is very nice.
Existing furnace can likely do this -- though not \"variable speed\" -- with
appropriate twiddling of thermostat control leads.

My next wishlist item is to add control for humidification as it\'s a
significant \"comfort feature\" in our dry climate.
 
C

Clifford Heath

Guest
On 4/8/20 2:20 am, Don Y wrote:
In the US, HVAC systems are controlled via low-voltage wiring
(to the \"thermostat\").

In most homes that I\'ve seen, this is just \"bell wire\" run
through the wall interior exiting through an /ad hoc/ hole
to connect to the thermostat from the rear.

Has anyone encountered a Jbox in this location (devoid
of mains voltage)?
Sorry I can\'t answer that. But existing eyes on this thread might be
able to answer a related question of mine.

We have a recent Daikin inverter system with ducting to three zones in
our home. The controller on the wall below the return is the cheapest
nastiest and most buggy bit of human interface I\'ve ever seen on any
machine. Each button press must be SLOOOOOW and deliberate, and half the
time even that doesn\'t register, even after multiple repeated attempts.

It\'s simply atrocious to use.

Daikin want $600 or something for more advanced controls (e.g. WiFi),
and to preserve this punitive pricing, they are protective of the
electrical and communications interface that drive these wired remote
controllers. It\'s a simple two-wire interface that sits at about
15.5Vdc, and judging from the fact that ours is wired with the red
negative, black positive, it must hang off a full wave rectifier so
illiterate installers don\'t have to care about polarity. Beyond that, I
haven\'t looked at the communications - that\'s on the cards though. I
suspect it\'s a multi-drop system too, but could be wrong on that.

I had purchased without checking, because I was convinced I could find
details somewhere on the Internet of someone having decoded the
interface and published it, sufficient that I could build my own Arduino
or ESP86 controller with touch screen.

Nada.

Has anyone here attempted this, or know of a source for protocol
documentation?

This company deserves to go down, for over-charging for complete crap!

BTW, Rinnai use a similar two-wire non-polar system for the water
temperature controllers on their Infinity hot water systems (and these
definitely do allow multiple units on the same wire pair). At least
those controllers are reasonably nice and not inordinately expensive.

Clifford Heath
 
M

Mikko OH2HVJ

Guest
Clifford Heath <no.spam@please.net> writes:


We have a recent Daikin inverter system with ducting to three zones in
our home. The controller on the wall below the return is the cheapest
nastiest and most buggy bit of human interface I\'ve ever seen on any
machine. Each button press must be SLOOOOOW and deliberate, and half
the time even that doesn\'t register, even after multiple repeated
attempts.
....
Has anyone here attempted this, or know of a source for protocol
documentation?
At least in Europe there are some multivendor boxen that talk
WiFi/GSM+SMS and send IR commands to the units. That\'s the way I\'m
remotely controlling some heat pumps.

Looks like Daikin IR format is available, could you use that ?

https://github.com/blafois/Daikin-IR-Reverse

--
mikko
 
C

Clifford Heath

Guest
On 12/8/20 9:00 pm, Mikko OH2HVJ wrote:
Clifford Heath <no.spam@please.net> writes:


We have a recent Daikin inverter system with ducting to three zones in
our home. The controller on the wall below the return is the cheapest
nastiest and most buggy bit of human interface I\'ve ever seen on any
machine. Each button press must be SLOOOOOW and deliberate, and half
the time even that doesn\'t register, even after multiple repeated
attempts.
...
Has anyone here attempted this, or know of a source for protocol
documentation?

At least in Europe there are some multivendor boxen that talk
WiFi/GSM+SMS and send IR commands to the units. That\'s the way I\'m
remotely controlling some heat pumps.

Looks like Daikin IR format is available, could you use that ?

https://github.com/blafois/Daikin-IR-Reverse
No. All the units that implement the Daikin protocol are $hundreds,
including the IR ones.

However, since I last searched, there has been new activity that gave me
some new pointers:

<https://community.openhab.org/t/integrating-a-daikin-a-c-system/31888/22>

.... which talks about the protocol being DIII-NET. It seems some company
had figured it out and produced compatible controllers branded
\"CoolMaster\" as far back as 2008, but the details were still unreleased.

The hardware interface seems to be HBS \"HomeBus Specification\", which is
a standard of the Electronic Industries Association of Japan. There are
chips that implement the interface, and I\'m searching for the data rates
and packet formats now...

<http://pdf.datasheetcatalog.com/datasheet_pdf/mitsumi-electric/MM1192XD.pdf>
<https://cdn.datasheetspdf.com/pdf-down/M/M/1/MM1007-MITSUMI.pdf>

It looks like even Maxim has got into the game:

<https://www.maximintegrated.com/en/design/technical-documents/app-notes/7/7224.html>

Bingo - I might have hit the jackpot. I might try patching into the
network and seeing what I can learn.

No idea if Rinnai use the same protocol, but it\'s likely the same hardware.

Clifford Heath.
 
G

Grant Taylor

Guest
On 8/12/20 12:51 AM, Don Y wrote:
> Yes, but we tell it to adjust the temperature to do so.

With the \"boost\" idea that I\'m talking about, you don\'t need to change
the temperature. Much less remember to change it back later or rely on
a fancy enough thermostat to do it for you.

> This is just a *temporary* change to the setpoint;

But it /is/ a /change/ to the set point.

I\'m advocating that there is no need to change the set point if there is
a \"boost\" type functionality.

once it is attained, the old setpoint is restored (so you don\'t have
to remember that you\'ve CHANGED the setpoint).
That presumes that the thermostat is intelligent enough to do that. Ye
old mechanical mercury thermostat will decidedly /not/ restore itself to
the old set point.



--
Grant. . . .
unix || die
 
D

Don Y

Guest
On 8/12/2020 9:35 PM, Grant Taylor wrote:
On 8/12/20 12:51 AM, Don Y wrote:
Yes, but we tell it to adjust the temperature to do so.

With the \"boost\" idea that I\'m talking about, you don\'t need to change the
temperature. Much less remember to change it back later or rely on a fancy
enough thermostat to do it for you.
Pretty much all thermostats are becoming \"fancy\", nowadays. Install
a new furnace or air conditioner and you\'ll undoubtedly end up with
a lot more than an old \"mercury switch on a bimetal coil\".

E.g., thermostats that notice when your PHONE is nearby and start to bring
the house back to \"occupied\" temperature while you\'ve been away, etc.

Soon, you won\'t be able to hook a \"dumb\" thermostat to an HVAC system.
(I\'m not \"intended\" to be able to control my evap cooler with anything other
than the control they provided with it; if that isn\'t fancy enough, they\'ll
gladly sell me a fancier -- proprietary -- controller!)

[They\'ve already got an MCU *in* the HVAC system and take pains to make it
talk to \"legacy\" wiring/controls. It\'s not hard for them to decide to
interface to legacy WIRING -- but with their own proprietary controls
dangling off the far end!]

This is just a *temporary* change to the setpoint;

But it /is/ a /change/ to the set point.

I\'m advocating that there is no need to change the set point if there is a
\"boost\" type functionality.
You\'re effectively changing the setpoint -- just not defining *what* you want
that setpoint to be! \"I want it warmer in here!\" The temperature could climb
0.1 degree... or 3 degrees! And, how it behaves tomorrow can be entirely
different.

(\"So? Hit the boost button again, if not enough!\" \"Then why have a
boost control if you\'re willing to keep turning the plant on manually??\")

once it is attained, the old setpoint is restored (so you don\'t have to
remember that you\'ve CHANGED the setpoint).

That presumes that the thermostat is intelligent enough to do that. Ye old
mechanical mercury thermostat will decidedly /not/ restore itself to the old
set point.
Nor will it \"boost\" the temperature, temporarily -- without modification!

Figure out what problem you\'re trying to solve instead of trying to
define a problem that fits a particular solution. E.g., when I recirculate
air (in those instances when the plant is idle), I want to *refresh*
the air in the house. I know I can do this in a fixed time interval based
on the volume of my interior and the flow rate of the blower. I don\'t want
to continuously recirculate it as that becomes costly. Just like you run a
whole-house fan only long enough to evacuate all of the stale air, replacing
it with fresh/cooler -- not *continually* doing so!
 
M

Michael Terrell

Guest
On Thursday, August 13, 2020 at 1:48:30 AM UTC-4, Don Y wrote:
On 8/12/2020 9:35 PM, Grant Taylor wrote:
On 8/12/20 12:51 AM, Don Y wrote:
Yes, but we tell it to adjust the temperature to do so.

With the \"boost\" idea that I\'m talking about, you don\'t need to change the
temperature. Much less remember to change it back later or rely on a fancy
enough thermostat to do it for you.

Pretty much all thermostats are becoming \"fancy\", nowadays. Install
a new furnace or air conditioner and you\'ll undoubtedly end up with
a lot more than an old \"mercury switch on a bimetal coil\".

E.g., thermostats that notice when your PHONE is nearby and start to bring
the house back to \"occupied\" temperature while you\'ve been away, etc.

Soon, you won\'t be able to hook a \"dumb\" thermostat to an HVAC system.
(I\'m not \"intended\" to be able to control my evap cooler with anything other
than the control they provided with it; if that isn\'t fancy enough, they\'ll
gladly sell me a fancier -- proprietary -- controller!)

[They\'ve already got an MCU *in* the HVAC system and take pains to make it
talk to \"legacy\" wiring/controls. It\'s not hard for them to decide to
interface to legacy WIRING -- but with their own proprietary controls
dangling off the far end!]

This is just a *temporary* change to the setpoint;

But it /is/ a /change/ to the set point.

I\'m advocating that there is no need to change the set point if there is a
\"boost\" type functionality.

You\'re effectively changing the setpoint -- just not defining *what* you want
that setpoint to be! \"I want it warmer in here!\" The temperature could climb
0.1 degree... or 3 degrees! And, how it behaves tomorrow can be entirely
different.

(\"So? Hit the boost button again, if not enough!\" \"Then why have a
boost control if you\'re willing to keep turning the plant on manually??\")

once it is attained, the old setpoint is restored (so you don\'t have to
remember that you\'ve CHANGED the setpoint).

That presumes that the thermostat is intelligent enough to do that. Ye old
mechanical mercury thermostat will decidedly /not/ restore itself to the old
set point.

Nor will it \"boost\" the temperature, temporarily -- without modification!

Figure out what problem you\'re trying to solve instead of trying to
define a problem that fits a particular solution. E.g., when I recirculate
air (in those instances when the plant is idle), I want to *refresh*
the air in the house. I know I can do this in a fixed time interval based
on the volume of my interior and the flow rate of the blower. I don\'t want
to continuously recirculate it as that becomes costly. Just like you run a
whole-house fan only long enough to evacuate all of the stale air, replacing
it with fresh/cooler -- not *continually* doing so!
The GE window A that I just bought not only came with a remote, there is an app to control it from a phone, or tablet.

GE 8,000 BTU AEK08LY 115V
It was $229 at Sm\'s Club.
 
A

amdx

Guest
On 8/11/2020 11:52 AM, amdx wrote:
On 8/3/2020 2:11 PM, John Larkin wrote:
On Mon, 3 Aug 2020 09:20:42 -0700, Don Y <blockedofcourse@foo.invalid
wrote:

In the US, HVAC systems are controlled via low-voltage wiring
(to the \"thermostat\").

In most homes that I\'ve seen, this is just \"bell wire\" run
through the wall interior exiting through an /ad hoc/ hole
to connect to the thermostat from the rear.

Has anyone encountered a Jbox in this location (devoid
of mains voltage)?
I\'ve never see a box for thermostat wiring.

In our cabin, I have a secret relay that parallels the thermostat, to
force the heat on remotely. More ad-hoc wiring!

I had that for years, but I had a button that I could push and make
the air conditioner come on for

2-1/2 minutes or switchable to 3-1/2 minutes. In the winter I moved a
clip lead to a different connection

and could do the same for heat. I used a latching relay, fet and a
timing capacitor with a resistor.

  When I got a new furnace installed with a new thermostat, the new
thermostat has at least twice

as many wires and never took the time to learn which wires to hook my
circuit to.

  The new air conditioner did a better job with humidity, so it
doesn\'t seem as important at it did.

Although I just looked and it\'s 78*F with 48% humidity. I\'d prefer
around 40%. This is my own fault, I went

for a walk and apparently didn\'t pull the door tight, when I got home,
I noticed the door cracked open 10 inches.

I grabbed a knife with a foot long blade and toured the house. I
didn\'t have to hurt anyone :)

 We do keep it at 78*F, after a few years of this, I feel chilly at
77*F, as long as the humidity is around 40%!

Mikek
Here is the schematic of my temperature bump circuit. I used it on a
mercury 4 wire thermostat.

I\'m sure it could be used on the multiwire smart thermostats, I just
haven\'t.

https://www.dropbox.com/s/cxigla1mm3qo9ph/thermostat%20temperature%20bumper.jpg?dl=0
                                                 Mikek

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
 
D

Don Y

Guest
On 8/13/2020 5:18 AM, Michael Terrell wrote:
On Thursday, August 13, 2020 at 1:48:30 AM UTC-4, Don Y wrote:

Nor will it \"boost\" the temperature, temporarily -- without modification!

Figure out what problem you\'re trying to solve instead of trying to define
a problem that fits a particular solution. E.g., when I recirculate air
(in those instances when the plant is idle), I want to *refresh* the air
in the house. I know I can do this in a fixed time interval based on the
volume of my interior and the flow rate of the blower. I don\'t want to
continuously recirculate it as that becomes costly. Just like you run a
whole-house fan only long enough to evacuate all of the stale air,
replacing it with fresh/cooler -- not *continually* doing so!

The GE window A that I just bought not only came with a remote, there is an
app to control it from a phone, or tablet.

GE 8,000 BTU AEK08LY 115V It was $229 at Sm\'s Club.
How do you retrofit the \"boost\" button to the remote? :>

Or, do you just bump the TEMPERATURE setting up/down, temporarily, to get
that effect?
 
M

Michael Terrell

Guest
On Thursday, August 13, 2020 at 11:57:52 AM UTC-4, Don Y wrote:
On 8/13/2020 5:18 AM, Michael Terrell wrote:
On Thursday, August 13, 2020 at 1:48:30 AM UTC-4, Don Y wrote:

Nor will it \"boost\" the temperature, temporarily -- without modification!

Figure out what problem you\'re trying to solve instead of trying to define
a problem that fits a particular solution. E.g., when I recirculate air
(in those instances when the plant is idle), I want to *refresh* the air
in the house. I know I can do this in a fixed time interval based on the
volume of my interior and the flow rate of the blower. I don\'t want to
continuously recirculate it as that becomes costly. Just like you run a
whole-house fan only long enough to evacuate all of the stale air,
replacing it with fresh/cooler -- not *continually* doing so!

The GE window A that I just bought not only came with a remote, there is an
app to control it from a phone, or tablet.

GE 8,000 BTU AEK08LY 115V It was $229 at Sm\'s Club.

How do you retrofit the \"boost\" button to the remote? :

Or, do you just bump the TEMPERATURE setting up/down, temporarily, to get
that effect?
I\'m at home 99% of the time, so I don\'t need any bump. I simply posted the information to show changes in the market. It will replace a 5,000 BTU unit, to improve performance on really hot days. You could program a learning remote to drive a new interface, if you are that desperate to tinker.
 
D

Don Y

Guest
On 8/13/2020 10:43 AM, Michael Terrell wrote:
On Thursday, August 13, 2020 at 11:57:52 AM UTC-4, Don Y wrote:
On 8/13/2020 5:18 AM, Michael Terrell wrote:

The GE window A that I just bought not only came with a remote, there
is an app to control it from a phone, or tablet.

GE 8,000 BTU AEK08LY 115V It was $229 at Sm\'s Club.

How do you retrofit the \"boost\" button to the remote? :

Or, do you just bump the TEMPERATURE setting up/down, temporarily, to get
that effect?

I\'m at home 99% of the time, so I don\'t need any bump.
Yes, I was speaking rhetorically. The remote undoubtedly has controls for
fan speed, cool/vent and temperature. Despite folks thinking they need to be
able to \"bump\" the output, vendors haven\'t considered it worth the cost
of an extra button!

> I simply posted the information to show changes in the market.

Yes, appliances are getting \"smarter\" -- regardless of how much of that
is actually exposed to the user. E.g., it\'s trivial to prevent an AC from
short-cycling, given that \"smarts\" are now present in most HVAC kit.

(Of course, you can\'t magically improve the comfort level provided
by an AC that \"wants\" to short cycle, but you can at least reduce the
wear on it)

Newer systems change their operating points based on how \"far\" they
have to move the ambient temperature -- switching to \"MAX\" when there\'s
a lot of ground to cover, then throttling back to a lower (quieter)
operating mode to maintain temperature.

It will replace a 5,000 BTU unit, to improve performance on really hot days.
You could program a learning remote to drive a new interface, if you are
that desperate to tinker.
 
G

Grant Taylor

Guest
On 8/12/20 11:48 PM, Don Y wrote:
Figure out what problem you\'re trying to solve instead of trying to
define a problem that fits a particular solution.
I did exactly that. I want the system to run for X number of minutes.
I presented multiple example cases of my problem.

You seem to not want to acknowledge or accept my problem. That\'s on
you. You\'re opinion of my problem doesn\'t make my problem any less of a
problem to me.



--
Grant. . . .
unix || die
 
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