LG Heat Pump Controls

GregWeiss

I have an LG heat pump and an oil boiler with hot water fin tube. I would like one thermostat to control both systems and fire the oil boiler based on a certain outdoor temperature. Does anyone have any experience with the LG multisite CRC2 control? LG model number PREMTBVC2

Any other solutions? 

mjgordon

I have the same question today with just different brands: my HVAC contractor just finished a Mitsubishi heat pump install yesterday and I have an old steam boiler system that I'd only like to run below 20F outdoor temp. My boiler is controlled by an ecobee3 Lite

EdTheHeaterMan

mjgordon said:

I have the same question today with just different brands: my HVAC contractor just finished a Mitsubishi heat pump install yesterday and I have an old steam boiler system that I'd only like to run below 20F outdoor temp. My boiler is controlled by an ecobee3 Lite

You can place an outdoor thermostat sensor connected to a thermostat inside that is set to come on at 20° outdoor temperature and perhaps go off at 25° outdoor temperature. This will operate a relay that has DPDT contacts. Common and NO contacts on one switch will close to operate the boiler on line voltage or low voltage. The other set of contacts can break the power to the Mitsubishi with the Common and NC contacts tis can be done in the control circuit or the line voltage to the indoor unit.

https://www.supplyhouse.com/Honeywell-T6031A1060-Remote-Bulb-Refrigeration-Temperature-Controller-with-30-F-to-90-F-setting-temperature-and-20-ft-capillary
https://www.supplyhouse.com/White-Rodgers-90-113-Fan-Control-Center-120-VAC-Primary-24-VAC-Secondary-SPDT-Relay

EdTheHeaterMan

GregWeiss said:

I have an LG heat pump and an oil boiler with hot water fin tube. I would like one thermostat to control both systems and fire the oil boiler based on a certain outdoor temperature. Does anyone have any experience with the LG multisite CRC2 control? LG model number PREMTBVC2

Any other solutions? 

That is not so easy. Since there is relatively no market for that technology, there is very little R&D dedicated to making that control. You are one of the 0.004% of Americans that really want something like that. Good luck!

archibald tuttle

It may be that working in an area with relatively little central air and enormous installed base of hydronic and steam that my take on the percentage of jobs where such a control would be useful is significantly more than @EdTheHeaterMan . Literally all the minisplits I see around here have conventional fossil backup of some sort completely independent of the minisplit. While there is some push and popularity (we'll see how deserved) for heat pumps without backup in new construction or full reno, especially on the coast and to the south of us, I see virtually none.

One could theoretically trick out some of the remote sensor thermostats by just putting your remote sensor outside but I haven't found one that allows you to chose a set point below 45 so the functionality exists but the programming blocks its effective use.

A bunch of the honeywell 'smart' thermostats. . . eer Residio these days - invensys went the other way, from fancy neo brand back to robertshaw but i digress–have a balance point setting. However honeywell in their infinite wisdom doesn't think that is an important feature to list on their comparison of all their thermostats and you have to wait til 9AM to chat or talk to anybody. I'm glad these folks have jobs and that there are some pretty decent people at honeywell support whom i've used in the past but I don't know what possesses them to ignore the low marginal cost of adding this option to their comparison chart.

But the other reason I can disagree that with the idea that there isn't a market for fairly broad parameter setting smart thermostats is that the utility companies are giving our money away like water as rebates for these things. I wish they would stop buying my neighbor's thermostat and just let me make the call and you'd get less rent seeking from manufacturers, distributors and installers driven by subsidies. But I guess that is about the 100th time i've said that on here.

EdTheHeaterMan

@archibald tuttle My percentage is based on @GregWeiss's specific system match up. Not a fits all for every possible scenario.

The problem with your proposed prospective that there are many more of these systems than one might think of
1. Each mini split system has proprietary control protocols i.e. Mitsubishi does not talk to Samsung or Samsung is not compatible with Fujitsu and so on.
2. Conventional thermostats for old school systems work on standard analog thermostat technology i.e. R, W, C, Y, and G for Heat and AC. with the addition of O/B and E or X or W2 for the reversing valve and backup heat.
3. WiFi thermostats for conventional systems, although digital in design still need to conform to the analogue terminal designation in order to be useful
4. Many of the higher efficiency "Conventional boilers, furnaces and heat pumps are offering communicating thermostats that send digital signals from the room sensors to the circuit board in the furnace/air handler and the outdoor unit condenser/heat pump. The conventional WiFi thermostats are not compatible with these systems. Also the communicating protocols are proprietary. Carrier won't talk to Lennox, York won't talk to Rheem/Rudd, etc.
5. In order to be a comprehensive, truly functional, smart control that can determine if the mini split or the central old school system is the most economical to get the job of "make me comfortable '' done properly, the device would need to understand every different control protocol and the operating cost of each energy source as it relates to that consumer in real time.

This technology is not impossible by any means It is doable with all the information available on the internet and by someone like you that can get investors to fund your idea so that you can purchase every possible HVAC device available and set them up in a laboratory to test each control protocol and how each can interact with your new device. This will include heating and cooling units, air filter devices and humidifier and dehumidifier units, Radon detection, exhaust fans, makeup air systems. and heat recovery units. Just for a start.

Then there must be a way to either connect with wires or wirelessly to this control and get daily updates on the cost of each type of energy that is available for indoor environmental comfort.

So when can we expect to see the results of your work Archie?

Is this the simple DIY install version?

archibald tuttle

@EdTheHeaterMan I'd be the first to agree with you that the alphabet soup attending today's controls may easily be jumbled, and yet a vague standard emerges. The main exception is that there seems to be an advantage to 'smart info' to the heat pump controller for advanced compressor designed heatpumps that use frequency modulation or other strategies to moderate output. Although this is another sticker shock problem where nobody told the guy who just bought these LGs I'm working on that to take greatest advantage of features he would need to unload another 25% of the cost on proprietary controls. Now this might not worry some people because they are buying these things with other peoples money! It bothers me because its my friggin money and i say, let them buy their own damn heat pumps.

Meanwhile the non proprietary LG operation is ironically old school. it appears to use Y and W terminals conventionally and the "O" decision is made in its own onboard controller. But you can trick out the heat pump mode of the honey well by putting the Y to the W during heating season. (we'll use a winter summer switch on the indoor unit so it can be returned to the Y terminal for AC operation). On the honeywell, the O and W are the same terminal but they provide a different function if the thermostat is told that the 1st stage is a heat pump. In that case the W/O terminal is constantly energized once the heat mode is selected and the call is delivered via the Y terminal and because the W/O is energized changing the 4-way valve, the Y becomes the heat call in heat mode. Or one might say, it remains the compressor call in both modes.

But in the abstract, there probably is no reason the industry could not standardize control even to access modulating function. Because they can still have proprietary algorithms and methods at the heat pump itself and they just need standard terminals that bring a standard (or even calibratable-is that a word?-resistance signal for room temperature back to the unit). That just is not that hard to standarize. It is deliberate integrated hierarchical marketing and industrial intransigence that is at least the prime mover in this industry disconnect insofar as i can see.

All that said, the Residio rep I talked to at ED OS is one of the first reps I ever talked to who really understands how the honeywill/residio staged thermostats work and how the contacts are assigned in different configurations and he walked me through the scenario I painted above of the winter summer swith using the VisionPro which will then, with correct mode selected for stage one, stage heat pump and conventional backup balance point very well and cost effectively without any additional proprietary or macguiver (Sp?) relay because it has an 'end switch" on the 8321 model (twin U1 contacts which effectively makes one of those an Rh2!) that can be assigned to the 2nd stage (not 100% sure if that is just its default assignment, although they offered to have a rep stop by and help me with initial setup of my first application. I was not honestly expecting that kind of responsiveness from the largest name in the business which i expected would rest on its laurels-albiet the residio label is young so maybe they got a little gusto to improve that brand recognition and penetration. Meanwhile, Tekmar, whom i would have expected to be leading the pack here and to have reverse engineered the needs for resistance rather than I/O signal does have Rh2 on its 563 but their reps are unable to relate to me that there is actually any logic in the control to use the outdoor temp to affect heat pump and backup operation even though it does have an outdoor temp sensor! WUWT (that's a little double entendre for all the guys over at the end of gas thread. And nevermind that Tekmar lead the crossover to setback which is the original system modulation and i would assume they would be working feverishly on addressing the differing manufacturers control strategies with one of their one-time industry leading controls. But, you know what they say about assume . . . .

In the meantime, I really have to study whether access to the variable frequency feature is really that important. It is kind of like the question of how important and cost effective outdoor setback and more continual operation and comfort are, compared to higher temp occupancy or time of day temperature regulation which requires quicker recovery and thus higher temps and more cycles. With variable frequency or other modulating heat pump tehcnologies, you save some electricity although you add extended time of operation to acheive same input of btus. you definitely would get less starts, and I think starts are the worst thing for an electric motor/compressor appliance so might get you better longevity, although just a decent soft start strategy along with a hunky capacitor might be cheaper insurance- and i haven't really looked at a entropy diagram that details the difference in cycle based on the difference in frequency but I suspect you probably get modestly lower pressures as it modulates down and i always think lower pressure is better, as against tiny leaks, etc. But even factoring that all in, I have yet to see what the energy and equipment life savings might be versus upfront costs and any maintenance issues arising out of the more sophisticated operation. So I'm keeping my powder dry. I think i'm going to suggest that this guy put one of his units on the LG controls and one on the Honeywell which means that one will run full capacity anytime it is called and we'll put loggin watt monitors on the two of 'em and see what happens.

nuff said . . . more than nuff probably

brian

EdTheHeaterMan

And everyone think I am long winded...

So, no TuttleStat in the near future?

Jamie Hall

I have to admit to some amusement when I look at all the efforts being put into smart this and smart that, never mind having some sort of industry standard control interface (which adds a horrifying amount of interface complexity when hooked to proprietary operation of the device, by the way).

I'm a pilot, or I was until my vision got to be not so good, and I've flown a variety of interesting aircraft (not type rated on them, but flown them), some of which -- later Airbus and Boeing models, for instance, have very sophisticated fly by wire computer controls. I've also driven a few different EVs with almost equally sophisticated (if not in some ways more sophisticated) computer controls.

Not directly comparable, but in every single case I've found that while when the magic is working, the magic can do a truly wonderful, economical, efficient job of running the show, when the magic quits or gets confused, and it always well, there is nothing invented yet which can do as flexible and reliable a job of flying the bird or driving or the car or, yes, keeping the temperature of the house, going the way you want it to go than the good old fashioned Mark 1 human brain.

Granted, that Mark 1 brain has to have some training or knowledge (although it's quite amazing what a complete novice can do with flying a plane, given some calm coaching) and has to be sober and refrain from texting, eating a Big Mac, doing their hair, or whatever -- granted.

archibald tuttle

@Jamie Hall

good analogy regarding proprietary fly by wire stuff and what is gained but conceivably what is risked when it fails . . . can you say 737 MAX . . .

but i think you are overplaying the difficulty of unity on an industry standard for controls because the key component lacking is simply two contacts that deliver resistance signal from a thermistor back to the brains at the heat pump. it is possible that some manufacturers have chosen to put some of the brains into the thermostat rather than onboard their heat pumps, so they become a less attractive choice in my book as a professional. they can have all the fancy proprietary algorithmic geegaws in the world (indeed I think they should have more such geegaws to effect need based defrost for our climate in the coastal northeast. But what is needed from the thermostat is different. now, there is some issue that, at least in some cases, resistance signals can be interfered with if the wires are not shielded so i don't mean to say there is no argument whatsoever for having the thermostat unit make those decisions on board, but maybe that is an argument for simply providing that the thermostat have backup communication with the heat pump via wifi, and then it can compare the wifi and wire info to watch for interference and/or the component can be installed without the need for cabling. Most of the generic smart thermostats have wifi now anyway!

In the end, I might elect to buy a simple nonmodulating heat pump and run it with a straightforward cold weather shut down and forego all the fancy ****. in the end, i'm unclear of the benefits of some of it compared to the higher costs. ditto the lower operating temp of some technologies that doubles the unit cost! But I still think a reasonably standard metric of control could be established. Will it happen? Anybody's guess.

@EdTheHeaterMan as to whether or not we have any tuttlestats any time soon, you're talking to the cabal that came up with the dwyerstat so this may be available before the 2023 model year :-)

Jamie Hall

The problem with the 737 MAX wasn't the airplane or the software. It did what it was meant to do (apply nose down trim with an increase in power). It was that the pilots of the two which crashed didn't know what that was, and forgot rule number one: fly the d__n airplane. A couple of Airbus aircraft have been lost to similar problems.

yesimon

Flair Puck Pro can do cutover based on outdoor temp by controlling your ecobee. The actual thermostat build quality leaves much to be desired though.

GGross

@GregWeiss

Lg offers a dry contact kit for using conventional thermostats. You will need to check with your dealer or supplier for compatibility. You would NOT use the LG thermostat if doing that. It should also be noted that using a conventional thermostat on mini splits will negate much of the internal control logic. Personally i recommend manual seasonal changeovers unless you want to dive in really deep with LG to figure out a communicating system that will also be able to enable your backup heat. I imagine this is possible depending on how much money you want to spend on controls, considering the number of commercial applications these are used in

We have done several homes that are on mini splits 100% of the time in tip of the mitt northern michigan

EdTheHeaterMan

With all that technology out there, sometimes the old school DPDT relay connected to the outdoor thermostat will get you there the way it did 70 years ago. I think I will send in for a patent for the Young-At-HeartStat while the TuttleStat is still in R&D.

Sug. Retail installed price $1500.00
Sug. Retail Delivered price & 150.00 (wires not included)

Looking for investors
Any takers?

archibald tuttle

Jamie Hall said:

The problem with the 737 MAX wasn't the airplane or the software. It did what it was meant to do (apply nose down trim with an increase in power). It was that the pilots of the two which crashed didn't know what that was, and forgot rule number one: fly the d__n airplane. A couple of Airbus aircraft have been lost to similar problems.

I believe the 737 max got bad readings from its pitch (or similar) indicators that is not bad software but its a vulnerable digital system for all its parts. I dont discount that the pilots potentially should have flown the plane. Im unsure if theur were analog gauges they could have relied om to do so. I respect this is an area of expertise for you so further observations?

Jamie Hall

The system in question on the 737 MAX was intended to apply nose down trim when the engines were throttled up; it was intended to be helpful (!) since with the big engines on the MAX there is a huge nose up trim change when the engines are put to full thrust. There have been some software modifications installed to avoid a situation where it could overcompensate which, however, have also made it somewhat less automatic feeling in its response. So far as I know there were no problems with the glass cockpit displays, but even had there been there are indeed analogue gauges as well. On the glass display, assuming it was working (and there's no evidence it wasn't) there are, at the least, displays for pitch attitude and airspeed (both duplicated for each pilot by analogue) and angle of attack. Out of trim forces on the controls can be quite high -- but manageable. The system can be completely disabled by switches on the control column, and switch as part of the flight control head., as well as being disabled by either pilot pressing his or her manual trim control (also on the yoke) or by using the manual trim control on the centre console.

Now I will agree that having excess nose down trim is not a common scenario -- but it does happen, and the solution should be reflexive: back pressure on the yoke to control the airspeed and get the other pilot to figure out what happened (or do it yourself, if you're alone in the front office -- but always fly the plane first).

Unhappily there have been a number of incidents -- and accidents -- where either the pilots had too much trust in the automation, or too little understanding of it, as well as a few where the automation failed for one reason or another and the pilots simply didn't know enough about flying -- stick and rudder -- to be able to understand the problem and recover (Air France 447 comes to mind)

archibald tuttle

Jamie Hall said:

The system in question on the 737 MAX was intended to apply nose down trim when the engines were throttled up; it was intended to be helpful (!) since with the big engines on the MAX there is a huge nose up trim change when the engines are put to full thrust.

. . . .

Unhappily there have been a number of incidents -- and accidents -- where either the pilots had too much trust in the automation, or too little understanding of it, as well as a few where the automation failed for one reason or another and the pilots simply didn't know enough about flying -- stick and rudder -- to be able to understand the problem and recover (Air France 447 comes to mind)

I would agree as a general matter with the later paragraph. Automation and computer supplementation overrides the use and practice of the basic skills necessary to do the job. The same kind of thing has come to apply to auto mechanics as diagnosis tries to catch up with a world of black boxes. But, I'm not sure that general truism applies with as much clarity to the 737 MAX accident circumstances.

After a little trolling the internet I recall what I suggested was a trim sensor which may actually also desribe the function was, as a term of art, an "Angle of attack" sensor. Your recollection in the first paragraph of what the MCAS system did is simplified or abbrievated. It may be that background MCAS added a little trim simply upon application of throttle without respect to input from the angle of attack sensor. But this recitation of the principal "cause" of the accident from Flight Global suggests: "The jets crashed after MCAS, responding to faulty AoA data from a single sensor, repeated applied nose-down stabiliser input."

From my less contextually informed understanding, that isn't just some standard modest trim function upon application of throttle but a significant override of the pilots actually flying the plane based on digital sensor input. And the black box read outs of the plane nose yawing up and down seemed actually to indicate that the anti-stall function of MCAS which more significantly applied horizontal stablizers was being fought by pilots who were flying the plane–thus the pattern of the MCAS pushing the nose down and the pilots pulling it up and their commands then being effectively countermanded by the software

Maybe by "fly the plane" you also mean switching off automated control functions and I'm not sure there whether there is a single simple way to do that that should have been the first instinct of piloting. It is pretty clear that the pilots weren't trained to recognize the particular part of the software at issue, but in discussing this as a failure of Boeing engineering, FAA oversight and pilot training, the storyline might indeed be ignoring that regardless of what software function was causing the idiosyncracy there was some kind of overarching software kill switch that might have been employed.

For all the focus on Boeing cutting corners–which it did–I haven't found any reporting on whether the training of the pilots (the area the press narrative suggests Boeing cut the most corners–and such narratives in the Erin Brockavich vein can be trite and misleading in some cases although there appears to be some fire with the smoke here, but I'm open to hear how the "fly the plane" paradigm suggests taking a more nuanced view than strictly: "evil corporate badguy") included generically taking full control in the event of unanticipated events, or any training at comparing the 'glass' readings to the analog readings during anamolous events (If I correctly understand your reference to glass as digital readings on 'glass' screen).

In some ways, I could analogzie the reaction to anamolies on the 737 MAX to the socalled "unintended acceleration" in Priuses. In that case I am not actually inclined to think there was software override of the driver but that the accelerator was in all likelihood affected by physical interference from body trim. Reports there had drivers say they shifted into neutral and the car went faster, which I tend to think was an incorrect inference of the engine sound increasing or changing as the load was released. And the response then is not to actual speed or actual inability to put the car in neutral and brake but to the cascade of events. IIRC there was evidence of the pilots reacting to the 737 MAX anamolies by turning off various computer functions but they imagining that they were somewhat disoriented by the what the automation had done and may or may not have actually turned off or only temporarily turned off the MCAS which, according to this "corporate bad guy" documentaries was not independently addressed in the flight manual. Now, there is noone more skeptical of something that comes from PBS than me, and I would be quite gratified to hear that there is a simple way to disable all automated inputs and fly the plane and that this would have been the most appropriate pilot reaction and should be the predominate pilot training and inclination regardless of the understanding of each codecil of flight control software.

As @EdTheHeaterMan points out, an analog refrigeration thermostat and DPDT relay is the non MCAS way to go about switching between heat pump and conventional. It is relatively inexpensive and simple and if you reviewed the dwyerstat you might recognize that, indeed your patented alternative is actually the current tuttlestat. The issue I have is that whether you are using the proprietary control or a more 'universal' multistage thermostat, the difficulty in teasing out balance point function when these controls have access to outside temp and to various measures of droop, i.e. speed of temperature drop in the interior space and/or lag in recovery, there just seems to be no excuse for the lack of a convenient call for the conventional backup.

And as @GGross points out, certain functionality is inaccessible if using genercic I/O thermostat. And one answer to backup is to design buildings and systems that don't require it: "We have done several homes that are on mini splits 100% of the time in tip of the mitt northern michigan ". There I ask, what is the COP acheived at the times most designers would invoke backup. Still, if starting from scratch, new construction or fullish reno, the average COP with superish insulated structure might be sustainable and outweigh the cost of backup–although 100% of the jobs i'm dealing with are hybrids, insulated as best they can be during partial renos and with existing conventional backup.

I tend to think that is a large enough segment of the market that some manufacturer ought to focus on it, indeed the industry might want to collectively focus on it, because if people start getting electric bills with 32¢ per kwh pricing and their heat pumps are spending any notable length of time below 3 COP, they are not going to be happy with this all but force conversion that government and industry types have locked arms on in fascist fashion (I like alliteration but that is meant as descriptive more than derogatory, although maybe the current connotation is too loaded so substitute "corporatist" if it helps). And the future of heating might look metaphorically like biden going to beg the Saudi's for oil after foreswearing to develop it here.

Jamie Hall

A quick sort of response here. Yes, you are correct in that apparently the angle of attack sensor on one channel did provide erroneous data (part of the software change was to have both AOA sensors active, rather than just one at a time) and that was the immediate cause of the repeated nose down trim activation. So far, so good.

That said, that does not excuse either recongising that the trim was misbehaving, not failing to turn it off immediately. Sorry. As I said, rule one is fly the d__n airplane. At this point, I can imagine a Parris Island type exchange: Did the controls become heavy nose down? Yes, sir. Did you turn off the trim with your yoke pushbutton? No, sir. Why not? No excuse, sir.

Frankly, your argument is exactly the same as the newspaper line "the car went out of control and hit the tree". With an automated car, true, that may be correct -- but with any car on the road today, it isn't. The honest line is "the driver lost control of the car and the car hit the tree". There is a difference.

archibald tuttle

Jamie Hall said:

Did you turn off the trim with your yoke pushbutton? No, sir. Why not? No excuse, sir.

that's exactly what i asked. is there a standard shutoff for automated functions regardless of whether thats MCAS or other autoassist or autopilot functions? you seem to say that is a standard yoke button. If so that tends to undermine the PBS theory about the lack of specializd pilot training for MCAS being at the root of this.

EdTheHeaterMan

This is getting very interesting. @GregWeiss wants to know if anyone makes a thermostat that can control his LG and Oil Burner in one control... Now Archie and Jamie have the poor guy in some Flight Simulator trying not to crash a 737 MAX into the ocean.

I'm applying for the Young@HeartStat Patent first thing in the morning. I'm on the next flight to the patent office in DC. (only if it is an AirBus)

archibald tuttle

EdTheHeaterMan said:

This is getting very interesting. @GregWeiss wants to know if anyone makes a thermostat that can control his LG and Oil Burner in one control... Now Archie and Jamie have the poor guy in some Flight Simulator trying not to crash a 737 MAX into the ocean.

who said they were over the ocean. . .

well the crashes being retold on the heating side are when the O is treated like a W and its heat 24/7. not exactly a sensor failure, just a sense failure.

Although I get the logic, instead of thinking of the Y as the AC call you think of it as the compressor call and then the O just signals for heat or cool. In any event, I like simple analog things but there are some things I want done digitally based on alogrithmic treatment of various inputs and then custom digitial control can make sense. I might have to do it myself, see, e.g, this differential stat. guy just made this cause the big "I" industry didn't. Then it will be: young@heart vs. old@fart.

Jamie Hall

archibald tuttle said:

Jamie Hall said:

Did you turn off the trim with your yoke pushbutton? No, sir. Why not? No excuse, sir.

that's exactly what i asked. is there a standard shutoff for automated functions regardless of whether thats MCAS or other autoassist or autopilot functions? you seem to say that is a standard yoke button. If so that tends to undermine the PBS theory about the lack of specializd pilot training for MCAS being at the root of this.

The kill button on the yoke -- on both Boeings and Airbus aircraft -- almost always does just that (there was one fascinating experience on a British Aerospace aircraft recently where it killed the autopilot, but not the servos -- interesting readig) and reverts your aircraft to direct mode. There are four other ways to kill the autopilot control as well. The PBS report is a nice PC attack on Boeing, but... leaves much to be desired otherwise. That said, you do have to recognise that you have a trim problem and then decide to do something about it, rather than just fighting it.

archibald tuttle

@Jamie Hall

I take your point. A flying the plane attitude would have corrected attitude (sorry . . . not really) by simply killing any automated assist rather than trying to get out a checklist to see which software genie was causing the problem. I'm not saying, in terms of design and training shortcuts, that Boeing doesn't come in for the lions share of criticism in the lion air crash (damn, did it again), but of course PBS only ever wants to twist the knife in the corporate bad guy. Just like with their attitude about climate change, the problem is Exxon, never the guy who wants to drive his car.

And it does seem to me that Boeing tried to have it both ways, because this particular set of software interventions followed from their decision to avoid redesigning the relatively stubby landing gear that prevented tradtional placement of large diameter more efficient engines on the existing platform, or, alternatively, engage in the herculean task of creating a new airframe model to replace the 737. So newer more efficient engines that were much larger in diameter had to be mounted forward of the wings on arms, i.e. levers, which created this effect where thrust was converted to torque through the mount–posing more risk of accidentally placing the plane closer to a stall attitude by adding thrust.

Now it isn't that I don't recognize flying has always been about balancing the controls since the Wright Brothers, and their innovation was NOT about how to get a plane off the ground, but how to keep it off the ground by quick subtle adjustments taking into account the constantly changing atmospheric conditions at small spatial intervals that could contribute to small differences in flight characteristics between one side of the plane and the other. Their brilliant solution, wing warping, effectively modest flaps differentially applied on either side of the plance, and even more brilliantly implemented by its activation through a cradle that they lay in when flying so if the plane banked right they would naturally slide right on the cradle which, through perhaps the earliest application of "aircraft cable", applied the equivalent of right flaps to right the plane. So it was almost automotonic or automated in that sense.

Even if Boeing and the airlines had had 737Max pilots spend more expensive training time flying the aircraft without software assist to learn to anticipate this effect, i'm unclear whether this effect would have been akin to simply switching between plane models with different flight characteristics or whether it was more hairtrigger sensitive or difficult to master. As we confound @EdTheHeaterMan by talking about this effect thought to be tamed by software in the aviation industry in discussing which effects or choices in heating system design ought to be given over to software, I am struck that it may indeed have been an area best managed by software but that impeaches the design decisions that lead to that point. It sure seems to me like the plane could have been flown without software but in the eventuality that that was necessary was it a question of learning a new 'feel' that would become all but autonomic or a constant delicate balance that made the plane difficult to fly with normative level of focus and concentration without that software?

In some idle moment on some human interest tidbit on Michael Crichton (who could have helped cynics like myself by participating in our thread about the end of gas) famously observed through a character's line in Jurassic Park that when the pirates of the carribean ride broke down, the anamatronic pirates didn't eat the riders. While @GGross observes that access to some functions on heat pumps may be lost because of inaccess to internal control logic, but will that eat the heating system or the homeowner? I continue to wonder the importance of the functions involved and whether they could indeed be accessed if the industry simply adopted relatively standard temperature and humidity resistance signals for generic thermostats.

With the LG, and I haven't taken their training yet so I'm kind of incrementing my knowledge from various sources, heating help not least of those, the access to variable frequency is interrupted. This is vaguely analogous to modulating in a fossil boiler and may be useful for energy conservation, although modulating in gas boilers is aimed at acheiving condensation, so there is notable capture of latent heat in exhaust that is the target and a notably source of efficiency. I haven't noticed much savings simply modulating non condensing boilers down to a 140 return threshold. I have used ODR and more constant operation as an approach to aesthetic comfort but I'm not particularly convinced it is much of an energy saver. Maybe there is a comfort and slight energy advantage to producing less btus over a longer period than cycling more often. I'm unclear on how that affects longevity of the equipment, thinking less starts is better. But overmuch it appears that LG may be using it for clever very low reverse operation to keep the outdoor unit defrosted so it is ready on call. If you have backup heat, inopportune defrost cycles and low outdoor temps can be managed with backup anyway; and depending on the extent of defrosting needed neither $ not btus are necessarily impacted. So flying without some aspects of the heatpump software isn't a problem.

Maybe there are other instances or implementations where important functionality is lost? Maybe there are also arguments about interference and the robustness of transmitting a resistance signal over distance and through connections although I have had pretty much bombproof results with regular thermostat wire on the remote sensor operation of robertshaw, nee invensys, 9000 series units. Not like i'm not ready for argument. . . :-)

pedmec

WOW. Now i got to go to flight school to fix HVAC systems. What the hell just happened!!!!

archibald tuttle

pedmec said:

WOW. Now i got to go to flight school to fix HVAC systems. What the hell just happened!!!!

just flying the heating systems by the seat of our pants

GregWeiss

My system is using an LG ducted air handler.  It actually has dry contacts built in.  However, I have been told I will loose efficiency if not using the LG controls.  The control I mentioned at the start of this thread does seem to have the capability but it’s pricey and I think I will also need an LG auxiliary relay.   I was hoping to find someone that has already tried this control.    🛩🛩🛩