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Re: ACbrrr monitoring

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On 4/1/2017 9:18 AM, Neon John wrote:
> On Fri, 31 Mar 2017 19:22:40 -0700, Don Y
> <blockedofcourse@foo.invalid> wrote:
>
>> On 3/31/2017 5:36 PM, Neon John wrote:
>>> On Fri, 31 Mar 2017 15:53:19 -0700, Don Y
>>> <blockedofcourse@foo.invalid> wrote:
>
>>> So what inputs do you hope to use?
>>
>> Gee, I dunno.  Maybe I should POST A MESSAGE asking along those lines?  :>
>
> But your question is like asking "how can I instrument a car engine to
> predict failure?".  There is no general purpose set of parameters that
> apply to all types of systems.

I can spend years becoming expert in the technology -- only to watch it
continually evolve.

Or, I can look for ideas towards an "80-20" solution and make PROVISIONS
to address them.

Clearly, oil fired hot water heat differs from gas forced air.  And, both
differ from a pellet stove.  Just as an evaporative cooler differs from
an ACbrrr which differs from a natural gas fired cooling.

I.e., there are obviously different approaches to the problem and different
application domains.

But, that doesn't invalidate the concept of instrumenting those plants
and installing local expert systems to advise the "users" of recommended
PM as well as anticipatory and reactionary diagnostics.

Doing it in an existing "dumb" installation is costly -- because there are no
mechanisms by which the kit can talk to the user.  The interface is just
a set of switches (heat/cool/fan/off) and settings (temperature).

*And*, because the kit can't talk to anything ELSE that could assist it
in determining the efficacy of its operation.  It doesn't know how hot/cold
it is, outside.  Or, if the wind is blowing.  Or, if it is humid.  Or, even
if the *sun* is up!

It can't talk to other such units -- directly or indirectly via a shared
(remote) knowledge base:   "Gee, this model ACbrrr seems to exhibit the
following failure mode(s) in these usage conditions..."

Build more efficient ACbrrrs that continue to be isolated ISLANDS and
the problem will persist.  The "thing" that will tie them together will
be the HVAC contractor showing up when YOURS shits the bed.  Because YOURS
won't be able to know what to look for in itself and its environs nor to
learn from the experiences of other similar/identical units.

> To correct a mistake I made in the previous post, I went dyslexic with
> the refrigerant name.  It should be R-410a instead of R-401a.
>
>> It's *probably* more likely that its a dirty filter.  Regardless,
>> its easier for a user to CHECK a filter and, if that proves NOT to be
>> the problem, decide how much more effort he is willing to invest
>> before resorting to a service call.
>
> Thumbing through my Johnstone Supply catalog, I see that thermostats
> with a "filter" idiot light are available so presumably this feature
> is being offered.  I quit doing air conditioning many years ago and
> only do refrigeration now so I'm not up on the finer details of
> things.

I'd wager the light comes on after a fixed number of "blower hours".
It knows nothing of the quality of filter installed, the amount of
dirt/dust in the edifice, the pressure drop across its surface, etc.

Like changing the oil in your car after a fixed number of miles
driven -- or elapsed days.  And, ASSUMING that all cars lead
similar lives.

Given that there are at least two CPUs in most HVAC systems
(one in the furnace, another in the thermostat) it seems silly for
them to just twiddle their thumbs replacing a comparator and set
of hardwired logic!

>> IME, many folks are willing/eager to do their own service/maintenance.
>> However, they lack:
>
>> - the tools/ability to diagnose the problem
>> - knowledge of the system to identify the POSSIBLE causes
>> - the analytical reasoning to evaluate likelihoods of those causes
>>   (if your ACbrr doesn't cool, chances are that it is NOT because
>>   someone stole the compressor out of it!  OTOH, it *could* be that
>>   someone has stolen the copper lines feeding to/from it!)
>> - knowledge of the procedure to implement the repair
>> - ability to evaluate the success/effectiveness of their repair
>
> And most importantly, they lack the licenses needed to purchase
> refrigeration nowadays.

If your system needs recharging and/or evacuation, you have to
call a "professional".  But, that doesn't stop you from doing other
PM.  Or, from the system itself determining when more extensive
maintenance is called for -- before becoming "urgent".

>> Extend the AI so that it can share results with similar AI's and
>> "common problems with Model 123" can be merged into their rule
>> systems so the likelier remedies are more frequently pursued.
>
> Do you have any idea the number of brands, models and variations there
> are on the market?  Probably numbers in the thousands.  Add in the
> installer-induced variations in split units and the number of sets of
> data become enormous.

Do you have any idea the number of brands, models and variations there
are on the market of cars?  coffee pots?  personal computers?  cell
phones?  televisions?  Does any of that prevent owners of those
bits of kit from sharing their failure/repair experiences?  Does
it prevent those devices THEMSELVES from sharing their experiences
without requiring the owner/repairman to take explicit actions?

Do you think your car doesn't "tattle" on what its noticed about
its performance and your driving patterns when it visits the dealer?
Do you think the dealer -- and manufacturer -- DISCARD that information?

Why can't other INTERNETWORKED devices similarly share information?
Why does connectedness just mean "able to be controlled remotely"?

>>> You save a LOT more money by simply having a modern >20SEER system
>>> installed.  Hitachi has a hot-shit mini-split system that does 28SEER.
>>> And with the R401a refrigerant, they'll continue to provide hot air
>>> with it significantly below zero outside.
>>
>> So, all the existing systems should be scrapped and replaced, immediately!
>> And, all cars that weren't manufactured in 2017 should similarly be scrapped.
>> And, pickup trucks.  And...
>
> Stop putting words in my mouth.  A smart owner (or his consultant)
> should do a financial analysis on the system, taking into account the
> age of the system, the amount of energy it uses, energy cost,
> probability of failure and the resultant repair costs (all the major
> brand names are now offering 10 year warranties so repair cost drops
> out of the new unit column) vs the cost of simply replacing the unit
> vs scrapping the whole works and going mini-split.

Exactly *zero* of the ~200 homes in this subdivision have deviated from
the "single, central compressor" cooling system (I walk the neighborhood
daily).  One of the businesses that I visit has installed them (small
compressor/condenser on the rooftop; evaporator an eyesore on the wall
in each office space.

By contrast, perhaps 20% now have roof-mounted photovoltaics.  And,
probably 25% of the homes with pools have passive solar (pool) water
heating.

IME (for reasons outlined previously), folks don't "replace" HVAC systems
until they start exhibiting problems -- most typically refrigeration.
Two neighbors have (air sourced) heat pumps for heating/cooling.  Surely
they'd have considered it worthwhile to pay for gas to be run to their
homes -- especially when the gas lines were replaced two years ago and
the crews on-site!

>> There are homes here that don't have ductwork.  There are (expensive!)
>> homes that have ductwork retrofitted to the EXTERIOR of the building
>> (i.e., sitting out in the sun).  There are folks who can't afford
>> refrigeration -- which confounds the city as it tries to curtail
>> *water* use (evaporative coolers use a LOT of water!)
>>
>> I'm sure all of these folks would LOVE to have your 28 SEER systems
>> installed.  How do you suggest they purchase them?  And, install
>> them?
>
> Modification to the structure involves pruning a branch circuit to the
> location and drilling one single 1" diameter hole through the wall.

What do you do when you have no basement nor attic through which to run
that branch circuit?  Or, when you have to add a sub-panel to accommodate
the extra circuits (fed by the "old" compressor circuit)?  And, the walls
are concrete/slump block.

> A 14kBTU unit (great room or average den/kitchen) condensing unit is
> about the size of an old fashioned hard suitcase.  The evaporator is
> normally a rectangular unit that hangs on the wall.  However,
> evaporators can be had that are disguised to look like picture frames
> and ones that hang from the ceiling.  The condensing unit can easily
> be hidden behind shrubby and after initial cool-down is so quiet as to
> be practically un-noticeable.

Shrubbery?  We live in the *desert*.  You want me to have one of these for
the living room (maybe it can bleed over into the dining room, as well).
Another for the kitchen and family rooms.  Something else to address the
bedrooms (in concert?) -- and hope the spillover handles the other
common spaces.  And, no one will notice these changes to the interior
or exterior of the house?

> Buying a unit is as simple as googling "mini-split heat pumps"
> (optionally adding a brand name) and selecting an on-line vendor.
>
> A crafty homeowner can do the installation with ordinary hand tools
> right up to charging the system with refrigerant.  A special R-410a
> license is needed to buy and work with the stuff because it is a very
> high pressure refrigerant.  Evaporator pressure at 70 deg is 201 psi.
> Condensing pressure on a hot summer day may be as high as 600 psi.  I
> have the license but I don't like working with the stuff even though
> the gauges, manifold and hoses are much more rugged than for more
> common refrigerants.
>
> There is a place in Brasstown Bald, NC called the Cambell School for
> the arts and crafts (or something like that) that is situated on a
> large 19th century farm.  Many of the buildings are made of stacked
> and cemented river rock.  Mini-splits have been installed in all the
> buildings.  They had someone paint the condensing units and the single
> line that goes indoors to match the surroundings.  I would have never
> known they were there had I not see an air handling unit hanging on
> the inside wall of one of the buildings.

And, who *paid* for all this?

Our next home will be below grade -- because it is just silly NOT to
exploit the insulating capabilities of earth (regardless of whether
you live in a cold or warm climate).  Far more effective use of
construction dollars than putzing around with insulation in walls,
ceilings, floors, triple glazed windows, etc.

But, you don't get from "existing structure" to "below grade" structure
just by spending money, /in situ/.  It's just *too* expensive to raze
a building and erect another in its place.

When you build "new", you can make allowances for where you want to
site the compressor, evaporator, furnace, utilities, etc.  When you
"start from existing", your choices are usually a lot more expensive
and constrained.

E.g., many homes have added water softeners/filtration systems, here
(our water is very hard and is continually degrading in quality as
demand outpaces growth of supply).  But, all water mains enter homes
through the front yard after passing through a meter at curbside.
Once at the home, the line immediately dives into the slab and feeds
the fixtures throughout the house.

So, adding anything upstream of the house requires it be sited in
the front yard -- at whatever place the supply *happens* to connect
to your home!  *Or*, intercepting the main as it enters the property
and routing it to some other place where the equipment can be installed
(i.e., outdoors!); then returning the treated water to the point of
interception to enter the house properly.  I.e., you can easily spend
$2000+ on the *installation* of a water softener -- trenching around the
perimeter of the house, burying the 100 feet of 3/4 - 1" pipe, tying it
in to the severed main and inlet, etc.

Then, worrying about how you were going to protect the equipment
from the weather, packrats, etc.  *And*, where you'd be storing all
the "salt" that would make servicing the brine tank convenient, yet
not require it to be stored outdoors, as well.

In other parts of the country, this would be cutting the supply line,
sweating a couple of fittings and setting the unit in place.  Then,
piling your salt supply near the brine tank.

So, folks buy bottled water (stupid!) instead of addressing THEIR
water supply.  That $2K (plus the cost of the kit itself) is a mighty
big hurdle for most to get past!

Similarly, our municipal water pressure is ~120psig.  Most water fittings
(dishwasher, washing machine, dryer, water softener, irrigation system,
evaporative cooler, toilet, etc.) are designed for a nominal 80psig
maximum.  Fixing this problem requires installing a pressure reducing valve
upstream of the municipal water supply inlet.  It's a small device -- about
the size of your palm -- unlike the behemoth water softeners.  So, its
conceivable that you could slip one in the supply line as it exits the
ground and passes into the exterior wall of the house (before diving into
the slab).

A PRV runs about $75.  And, as its relatively little labor to install
(i.e., no trenching around the house; just two joints to sweat), you
could probably get one installed for $200.  So, figure $300 out-of-pocket.

I doubt 10% of the older homes in the neighborhood have one (newer homes
do because of code changes -- the city *knows* the supply is operating
well above the expected maximum for most appliances/fixtures).

Of the homes that have PRV's, I've yet to find one that has the "required"
expansion tank on the load side!  Because finding a spot for a cubic foot tank
AND plumbing it starts to make it a more complicated/expensive endeavor.
So, even when installing a "PRV with bypass", the home is no better off
(worst case) than they were, without the PRV!  The water in the NOW CLOSED
SYSTEM expands as the water heater makes up for consumption.  This quickly
raises the pressure in that closed system to well above the original
"high supply pressure" -- until the bypass vents it back into the municipal
supply.

And, these are relatively "low tech" sorts of upgrades.  But, people
don't see the cost *avoided* by implementing them vs. the cost incurred
*to* implement them.  Most folks don't even know what the muni water
pressure is nor what it *should* be!  Do *you* have a pressure gauge
on your water inlet?  (Of course *I* do!  As well as downstream from the
PRV -- to assure myself that it is, in fact, working!)

> So in summary, if you can drill a 1" hole through an outside wall, you
> can install mini-splits.
>
> Mini-splits are so refined because they are what most of the rest of
> the world uses where energy is expensive and incomes are low.  Look at
> a photo or video of most any foreign high rise and you'll see little
> mini-split hanging all over the buildings like ticks on a dog.
>
>> Gee, so obviously the idea of instrumenting an HVAC system has occurred to
>> someone!  It's so reassuring to know I'm on the right track!  ;)
>
> 25 cents/kWH for electricity, what my partner in San Diego pays after
> the first 1000 kWh spurs many such optimizations.

I think we're paying about half that.  We'd save more by discarding the
freeezer (sitting out in the garage), unplugging the various wall-wart
powered devices scattered around the house (even at < 1W/each, having
dozens of them adds up!) and forcing the computers to "sleep" more
aggressively (there are 4 computers running, currently; two actively in
use, another servicing my network, and a fourth waiting for me to finish
this post so I can get back to "work").

But money is only part of the equation.  There's also comfort/convenience
(its no fun to lose cooling/heating when you NEED it -- and, you only know
that it is gone BECAUSE you need it!).  And, there is the "independence"
factor:  being able to continue to live in your own home (vs. a retirement
home or assisted care facility) without having to keep a lengthy list of
all the "things" you should be checking on -- or hiring someone to check
on FOR you.

Do you regularly visit your folks (or kids!) to ensure the house is "intact"
to address their anticipated needs for the next month (or five)?  Do
*they* remember to change the filter in their furnace?  Or, have the
compressor serviced?   Check the evaporative cooler for leaks?  etc.
It's April -- time for me to make my annual survey of the condition of
the roof (so I can affect repairs before it gets too hot *or* Monsoon
starts)...

Wouldn't it be nice if those things could remind them of these needs?
Or, *you*, on their behalf?  Instead of warehousing them in a $3-4K/month
"facility" that relieves them of those concerns?

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Thread

ACbrrr monitoring Don Y <blockedofcourse@foo.invalid> - 2017-03-30 14:31 -0700
  Re: ACbrrr monitoring Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-03-30 14:49 -0700
    Re: ACbrrr monitoring Don Y <blockedofcourse@foo.invalid> - 2017-03-30 15:02 -0700
      Re: ACbrrr monitoring Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-03-30 15:16 -0700
        Re: ACbrrr monitoring Don Y <blockedofcourse@foo.invalid> - 2017-03-30 15:45 -0700
  Re: ACbrrr monitoring Neon John <no@never.com> - 2017-03-31 18:08 -0400
    Re: ACbrrr monitoring Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-03-31 15:33 -0700
      Re: ACbrrr monitoring Don Y <blockedofcourse@foo.invalid> - 2017-03-31 15:53 -0700
        Re: ACbrrr monitoring Neon John <no@never.com> - 2017-03-31 20:36 -0400
          Re: ACbrrr monitoring Don Y <blockedofcourse@foo.invalid> - 2017-03-31 19:22 -0700
            Re: ACbrrr monitoring Neon John <no@never.com> - 2017-04-01 12:18 -0400
              Re: ACbrrr monitoring Don Y <blockedofcourse@foo.invalid> - 2017-04-01 11:17 -0700
                Re: ACbrrr monitoring Neon John <no@never.com> - 2017-04-02 12:26 -0400
                Re: ACbrrr monitoring Don Y <blockedofcourse@foo.invalid> - 2017-04-02 14:42 -0700
    Re: ACbrrr monitoring Don Y <blockedofcourse@foo.invalid> - 2017-03-31 16:06 -0700
      Re: ACbrrr monitoring Neon John <no@never.com> - 2017-03-31 20:53 -0400
        Re: ACbrrr monitoring Don Y <blockedofcourse@foo.invalid> - 2017-03-31 19:38 -0700
          Re: ACbrrr monitoring krw@notreal.com - 2017-03-31 23:11 -0400

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