Thermostats can be defective or can go bad. Any hvac tech should be able to make adjustment or replace the thermostat. The problem might be as simple as sensor bulb loose or out of position. The installing contractor might do it free or parts only. The most dependable unit made will not preform right if t-stat is defective.

Daikin is the biggest manufacturer of HVAC equipment in the world. They don't make defective stuff. Get the installer back to fix the problems.

" They don't make defective stuff. "

Sure they do. They all do. Daikin owns Goodman, far from the top name in split system HVAC equipment in the US.

The problem could also be an inept installer. No way to know from the description.

"The problem could also be an inept installer. "

Precisely. Dakin quality is as good as anybody's, but installers do all sorts of crazy things!

@sktn77a,

By way of clarification, there are HVAC new installation contractors, HVAC replacement contractors, and contractors who offer both services (at least in our market.) The competencies required for new installation contractors are markedly different than those of contractors uncrating and installing plug-and-play replacements. Problems can--and do--arise when either puts on the hat of the other. Houzzers will be well served to consider the differences when choosing a HVAC contractor.

UPDATE: The hvac contractor came back to get the Daikin mini-split unit functioning again. Turns out the error codes accessible via the remote thermostat did not identify the problem. I never did get any good explanation for what caused the unit to go down for the second time in ten months, for the hvac contractor was unable to determine what went wrong. He initially indicated that the culprit was low refrigerant until I questioned what role the refrigerant level played in the heating function. He did a bit of this and a bit of that over the course of three plus hours with his assistant's help. The Daikin unit has now been functioning for several days. The test will be when I switch from heating to cooling, for switching from one mode to another seems to be the trigger. In the meantime I stand by what I said: Spend the additional money on a Mitsubishi unit.

He initially indicated that the culprit was low refrigerant until I questioned what role the refrigerant level played in the heating function.

Wm Walker, A heat pump regardless of brand will require proper refrigerant charge for both modes AC or Heat mode.

The refrigerant is a specially designed solvent (more or less) that is used as a transfer medium for moving heat around. In the summer it attracts the heat inside your structure and transfers it to the outside condenser. The refrigerant level (charge of the system) plays other roles as well. So over charged as well as under charged will cause an assortment of problems for a heat pump.

In the winter the roles are reversed as your outside condenser becomes the evaporator that pulls heat from the outside and moves it to the inside. In the winter your inside equipment becomes the condenser when running in heat mode.

But it's cold outside in the winter there is no heat out there? It's true that as temps fall there is less and less heat to absorb and transfer indoors. The evap outside may freeze --- which is why the heat pumps are equiped with a defrost cycle. In addition to a second source of heat on the inside equipment usually in the form of electric resistance heat.

The reason they are called heat pumps? They pump heat regardless of the mode they are in.

There are various camps that believe one brand is better for a variety of reasons. In my experience based on 29 years of doing this for a living there is little difference in brands. I've installed over 8 different brands of equipment in the past 15 years the trouble comes most often in time passage. (How old the equipment is)

While some failures do come randomly this effects all brands fairly equally. Usually in the realm of 2% annually. I can say that because there are no outside sources messing up my statistics. I install / service & maintain all equipment I sell.

Previous jobs I've held working for other companies before I obtained my HVAC license? They gave warranty work a passing grade if it was 25% or lower (circa 2002 it may be different now). If you are doing everything yourself you can NOT afford to go back to 1 out of every 4 call requests you get in a years time. This is a time vs money game outside of all the technical problems.

This sounds like you have a big ego? I can't tell the story without it sounding that way.

I have a youtube channel that demonstrates much more than what I can put here -- I understand more than you how hard it is to believe what people say these days.

Turns out the error codes accessible via the remote thermostat did not identify the problem.

Yeah I've been seeing this alot here recently. The thing is these codes many of them only give you a short list of clues as to what may or may not be wrong.

Hopefully they found the problem this time around.

He did a bit of this and a bit of that over the course of three plus hours with his assistant's help.

It took two HVAC techs 3 hours to figure out why equipment installed in April was not working properly? Were any defective parts changed? It sounds more like installation problems than problems with the Daiken mini split. I suggest you try the cooling mode in early Spring while you are still under warranty.

"The refrigerant is a specially designed solvent (more or less) that is used as a transfer medium for moving heat around. In the summer it attracts the heat inside your structure and transfers it to the outside condenser." Sorry, but this characterization is so inaccurate houzzers deserve a correction. A refrigerant is a chemical. There is no solvation (dissolution of a solute in a solvent) involved in the operation of a residential air conditioner or heat pump, so the refrigerant doesn't function as a solvent--neither more nor less. Further, a refrigerant has no special ability to "attract" heat. It simply absorbs or gives up heat according to the laws of thermodynamics.

I value expertise and experience albeit without the snark. Frankly, the message gets lost in the snark. Deliver the pertinent facts in understandable lay terms without the extraneous fighting words if you truly want to be heard by those in need of your expertise, me included.

I won’t presume to speak for everyone on Houzz, but I tend to place more value on the practical advice of experienced tradesmen over general advice from a builder or general contractor. Different levels of expertise. Different functions. Vastly different skills in most cases.

Wm Walker, Fair enough.... however we don't live in a world that people do what you want them to. That would be called a fairy tale. If I am going to do this it's going to be real, not fake.

Understandable lay terms: I try to do my best where that is concerned. Is it perfect no. The job is a highly technical job performed in person. Not from a forum board. Influencers as well as other fakers IMO, are here for the clicks, the likes etc. (I am here for neither - those things don't matter to me and they're only going to dupe you. (unusable info))

Snark--- there was a time people liked to laugh. I know in certain parts of the country it's against the law to be happy. You have my sympathy.

I concentrate on being me... The reality is that the jobs I get (real ones that I go to in person) from this site posting the same as I always have since around 2016 or so are from those who read the board and don't post.

If you can't take my happy go lucky stance on a internet board, you probably won't be able to handle it in person either. But it goes further than that... I'm not a push over as I've illustrated in my repsonses here on this thread as well as others as well as in my video stories on youtube.

What you've read, heard or witnessed on the internet may not be of advantage to you. Consider your sources carefully. influencers are paid by producing click bait, not by doing real work. Fake it till you make it, lie, cheat and steal your way to success. Use degree(s) for things in which they weren't intended... not because they're useful for misapplication, but because they make you look like a more bonefide influential person.

I've provided resource to back up what I say. Instances of that particular use. I'll go a step further:

Water? how many different sources of water are there on this planet? are all of them potable?

Chemical elements: is hydrogen a chemical? how about oxygen? (note I am not a chemical engineer - I play one on Youtube) ha, ha, ha.

Chemical make up of water: H2O ( It was once used as a refrigerant before mechanical refrigeration and in certain applications it still is used.)

I purchased a Daikin split 2 years ago and I couldn't be more unhappy with it. This week, a valve was found faulty (via phone diagnostics with my servicer and Daikin) and needed to be replaced. Per warranty, they paid for the cheap valve, and I paid for labor and replacement of the freon leaked because of the valve. The unit still didn't work. So then I paid for lengthy diagnostic time my laborer spent on the phone with them to say that another part (Electronic TXV) needs to be replaced. They will send the part, but I'll be paying for the diagnostic time (again) and labor to install (apparently nobody has ever had to replace one, so we'll see how that goes), and I'm up to $1,500 in labor costs.

All Daikin ever has to say is "per warranty we only pay for parts." But when those faulty parts cause expensive fixes, they don't even consider being responsible. I'll never purchase anything else from this company again.

I suspect you major issue is with the installer. They clearly don't know how to fix the problem and are just throwing parts at it on your dime. Contact the business owner and if he doesn't remedy the problem, file a complain with the BBB.

So then I paid for lengthy diagnostic time my laborer spent on the phone with them to say that another part (Electronic TXV) needs to be replaced. They will send the part, but I'll be paying for the diagnostic time (again) and labor to install (apparently nobody has ever had to replace one, so we'll see how that goes), and I'm up to $1,500 in labor costs.

If your Daikin split AC system contains "Electronic TXV" that part is a requirement of a higher end system. So just saying brand name "Daikin" throws out the illusion that all Daikin units must be bad "because of one event, with the experience of one HVAC company. I get why you're angered, but it's not going to do much unless you better do the homework on the front end. If it's only about $$ which what you laid out makes it out as such?

How did you come about finding this HVAC company? How were they selected to do the install?

Cheapest price? Value added stuff you didn't really need or want? Bells and whistles like app control via cell phone? Communication this and that? (nearly all brands do the same thing like this in some fashion -- especially for a HVAC system with an Electronic TXV)

You have to realize that servicing HVAC equipment is a very technical job, of that requires continual continuing education to stay abreast of changes that are taking place at a much more rampant pace than anytime before. (Prior to this time period we used 1 refrigerant for over 50 years until a slew of changes have taken place in the last 20 years or so.

As a result an Electronic TXV was a never needed item 20 years ago.

It doesn't take a highly technical person or person(s) to install a complicated machine. It does how ever require one when that machine breaks (for whatever reason) HVAC regardless of make / model -- similar or worse problems can and do happen.

How is it or was it that the installing HVAC company sold you this machine? How many bids did you get? How long have you trusted this HVAC company for?

Without these kinds of specifics? Most likely you'll turn around buy a different brand from a different company, and repeat the same mistakes as you have here.

A brand doesn't make problems go away. If you live your life this way, you will never run out of different brands to try and blame all of them when they break. ( I work on broken AC's all summer long. There isn't a brand yet in over 30 years I have found that doesn't break.

I know none of this is what you want to hear, but the truth will set you free. (In the world you will have trials and tribulations -- HVAC related? yes there too.)

Realize there isn't an HVAC brand available today in which someone professed they would never buy that brand again.

For some reason I don't have half of these kinds of problems at my HVAC company? -- How could I have all this time of a morning to write long winded rants -- disecting and proving my points not just in this thread but also many other threads on this board as well?

My mother often told me: Too many cooks in the kitchen spoils the broth. Now apply this logic to HVAC and you'll start to begin to realize the difference. (not about being cheaper than everyone else, everyone else doesn't have the knowledge I possess. Oh so you're a know it all?

I know enough to know what to do, but more importantly "what not to do".

--------- So what does karenmaryvlm do now? ---------

Select another brand with yet another different HVAC company? The odds of that working out like you think it will are rather slim as we get ready to enter a new R410a refrigerant phase out. (R410a: 40% cut in 2024)

I service the Katy, Texas area.

"Prior to this time period we used 1 refrigerant for over 50 years until a slew of changes have taken place in the last 20 years or so.

As a result an Electronic TXV was a never needed item 20 years ago."

An electronic expansion valve, by definition, is not a TXV. A TXV or thermal expansion valve" is a purely mechanical device. The use of electronic expansion valves is not a response to changes in refrigerants used, but rather, an effort to provide improved control--particularly under partial load conditions and to enhance energy efficiency.

"The odds of that working out like you think it will are rather slim as we get ready to enter a new R410a refrigerant phase out. (R410a: 40% cut in 2024)"

Refrigerants have cycled in and out in an effort to reduce toxicity, improve stability, and increase energy efficiency since mechanical refrigeration was first introduced. That's around two centuries of change. If history is any guide, we'll survive the phase down of R410A. The sun will come up in 2025 and we'll still have air conditioning.

If history is any guide, we'll survive the phase down of R410A. The sun will come up in 2025 and we'll still have air conditioning.

Yep, using different refrigerant(s) at higher costs and those people complaining about the cost of maintaining a AC / Heat Pump will complain about never using xyz brand again, because the mentality here is about what?

How much you have to spend to maintain one. Those costs are only going up from what I see here moving forward. If you want to view this as fear: Yeah if you're griping over money now, you have more than 1 reason to be fearful if you want comfort cooling / comfort heating via a heat pump moving forward.

What have I said in other threads Charles? costs will drive the market, but if you don't understand what the market is going thru?

You'll spend even more money listening to others that don't actually do HVAC directly claiming that everything is going to be ok if you just stick your head in the sand and ignore the changes that are taking place.

You aren't going to blame me for your own foolishness. Take that to the bank.

Electronic TXV's are called EEV's the purpose of both (EEV vs TXV) is the same, the EEV's are controlled via stepping from an additional electronic device to gain a minute amount of efficiency. I run a high efficient Inverter that has no requirement of an EEV. Without an expansion device your AC heat pump won't work. EEV, TXV, Piston --- these are all expansion valves. Piston is the cheapest least complicated, but only to those with experience. (anyone can yak in a forum board)

I service the Katy, Texas area.

Ray,

You'll need to check your HVAC textbook. A thermal expansion valve or thermostatic expansion valve is a purely mechanical device; they don't have wires. An electronic expansion valve is a more precise metering device that is controlled electronically. It's not referred to an electronic thermal expansion valve. You're just spreading more misinformation.

It's not referred to an electronic thermal expansion valve. You're just spreading more misinformation.

That's not what I said. If you're going to argue Charles you can't do so by trying to put words in my mouth that are not there. I said EEV.

Electronic TXV is how the OP described it, not me. Given those clues I still know what it is, of which clearly you Charles -- DO NOT.

The T in TXV does not stand for thermal. -- Thermostatic. In some instances they are called TEV's but this is still thermostatic / not thermal. I have never heard this device called a thermal expansion valve.

EEV merely is the same thing in electronic form, that has a stepper motor of which is controlled by an additional electronic board.

Oh dear, here we go again................

It's a shut out, don't worry Sktn77a

click to enlarge.

The terms "thermal expansion valve" and "thermostatic expansion valve" are used interchangeably.

"Thermal expansion valves, or thermostatic expansion valves, are the expansion devices used most commonly with brazed plate heat exchanger evaporators. TEVs are popular expansion devices due to their simplicity and availability, and their relatively good sensitivity and accuracy in regulation." Source: https://www.swepusa.com/refrigerant-handbook/4.-expansion-valves/adf6/ It's gonna take more than refresher training....

But yet they don't call them that.

except the one place you show. Score 5 to 1.

I'll keep calling them Thermostatic, for the record.