Daikin minisplit not cooling

[scanchain]

I had a new install done in March for my basement -- Daikin 2-ton unit with 3 heads.

Since the basement never really gets very hot, I didn't really exercise the cooling function. Today, the basement temperature is 76F and I set the thermostat to 68F to check out cooling. The air coming out from the blower is not cold at all. I have verified that the outdoor compressor fan runs.

Is there any thing I can check out before I call the tech on Monday tomorrow?

 

[SALIV8]

Do a hard reset.

Turn off breakers, wait 30 mins then power back on.

 

[scanchain]

Do a hard reset.

Turn off breakers, wait 30 mins then power back on.

Thanks. Tried that and same result.

When I feel the copper couplings at the compressor, none of them is cold. I think this points to refrigerant leak?

 

[SALIV8]

Are you sure the remote/unit is in the proper mode? My units will show an error code if there’s a refrigerant leak.

 

[Ralf11]

I have Daiken heat pumps and there is some elaborate key combination you have to go thru to output the error codes.

Do you have a manual?

 

[scanchain]

Are you sure the remote/unit is in the proper mode? My units will show an error code if there’s a refrigerant leak.

Yes, I'm in the cooling mode.

For completeness, I just tried the heating mode (set to 85F) and the air coming out is the same room temperature.

 

[scanchain]

I have Daiken heat pumps and there is some elaborate key combination you have to go thru to output the error codes.

Do you have a manual?

I followed this, and press CANCEL for 5s. It shows 00. I then press CANCEL repeatedly and it shows

U4,L5,E6,H6,H0,A6,E7,U0,F3,A5,F6,...

I'm not sure what this means.

 

[jkeyser14]

I followed this, and press CANCEL for 5s. It shows 00. I then press CANCEL repeatedly and it shows

U4,L5,E6,H6,H0,A6,E7,U0,F3,A5,F6,...

I'm not sure what this means.

You have to listen to the beeps... Read the manual. A long beep means that is the error.

 

[scanchain]

You have to listen to the beeps... Read the manual. A long beep means that is the error.

Thanks. I get what you are saying now.

I get a long beep with 00, meaning the system is "normal". Each of the other codes is followed by a short beep.

 

[PCMusicGuy]

No idea what the issue is but those sure are a bunch of errors codes you site. Call the company and have them fix it. It should certainly still be under warranty.

 

[Donzi camino]

I have a daikin 2 ton and the thermostat is in the unit and not the remote. I have a digital thermometer and it never reads what the remote is set at. Typically i set remote on 67 and usually the garage is about 75, which feels great when its 90 outside. My numbers seem to reflect the numbers you have . If i set to the lowest 60 , then i get to about 70 in garage. Hope this helps

 

[Mesozoic]

That's hilarious, I have exactly the same problem (I think) with my new Daikin system. It's a 3-ton outdoor unit with 24K + 7K indoor units. The green LED on both indoor units is blinking and the system does not blow cold. I ran through the same error code determination and honestly, didn't read them correctly (long beep, short beep), so should probably do that now.

 

[scanchain]

I have a daikin 2 ton and the thermostat is in the unit and not the remote. I have a digital thermometer and it never reads what the remote is set at. Typically i set remote on 67 and usually the garage is about 75, which feels great when its 90 outside. My numbers seem to reflect the numbers you have . If i set to the lowest 60 , then i get to about 70 in garage. Hope this helps

This doesn't seem to be my case, because it does seem to cool several weeks ago with the same temperature setting.

 

[scanchain]

That's hilarious, I have exactly the same problem (I think) with my new Daikin system. It's a 3-ton outdoor unit with 24K + 7K indoor units. The green LED on both indoor units is blinking and the system does not blow cold. I ran through the same error code determination and honestly, didn't read them correctly (long beep, short beep), so should probably do that now.

Follow jkeyser14's post earlier. Keeping pressing CANCEL (press and release) until you hear the long beep. The two characters that appear on the remote is the error code.

 

[OldSoldier]

OP, you have a similar problem as me.

I have a Daikin multi-head unit and sometimes no matter what I do (a hard reset is basically my only tool in the shed) it ignores me and does what it wants. I set it for 78 and it won't cool at all (95+ outside). I set it for 74 and it continues to cool down to 66.
The codes are always UH and A5, but they rotate on one head or the other. Sometimes one head cools but the other doesn't, and then I'll come back into the shop and it is reversed. Sometimes it'll work for weeks and others it will poop out after 20 minutes. I think it is possessed. I've had the installer out several times, they don't know what to do about it. I've had the manufacturer out to look at it, they simply agreed to replace the outside unit with a new one (it also exhibited the same problems) because they couldn't properly troubleshoot it.

I think Daikin has a real problem with their US staff and installers not understanding or being properly trained by the Japan designers.

 

[scanchain]

Today, I decided to set the system to 65F and run with fan on med-high. As expected, the air is not cold. After an hour of so, I try to read the error code, and this time it tells me U0, which corresponds to "refrigerant shortage" (see the table I posted earlier).

After running for another hour or so, the system shuts down by itself and blinks the power LED.

I am still waiting to hear back from the installer to schedule a date to diagnose this. I guess at the peak of summer, the installer is busy and putting warranty issues on the back burner. What a disappointment!

 

[Mesozoic]

I have the same issue... I think the system is merely undercharged. I've got some epoxy floor action going on right now, so have delayed the contractor until next week - not currently using the space yet, but looking forward to that immensely!

 

[Ralf11]

could the 2 heads be working against each other?

are they both set the same way?

 

[scanchain]

could the 2 heads be working against each other?

are they both set the same way?

If they are not in the same mode, the system will shut down with the blinking power LEDs. This could be something as trivial as "fan" mode and "cool" mode (as opposed to "heat" and "cool" modes).

I am aware of that.

 

[scanchain]

Something I learnt today while experimenting with the system.

Upon a fresh start (breaker reset), the system starts with status code 00 (i.e. no error). I started the system in A/C mode and one of the refrigerant pipes did get a little cold to touch. After running this for about an hour, the compressor fan turns off and the system flags a U0 code (refrigerant shortage). This code remains until I do a breaker reset.

I think the compressor shuts off when it detects a refrigerant shortage.

 

[bazar01]

I had a new install done in March for my basement -- Daikin 2-ton unit with 3 heads.

Since the basement never really gets very hot, I didn't really exercise the cooling function. Today, the basement temperature is 76F and I set the thermostat to 68F to check out cooling. The air coming out from the blower is not cold at all. I have verified that the outdoor compressor fan runs.

Is there any thing I can check out before I call the tech on Monday tomorrow?

Nothing you can do really but wait for the warranty service order from the company that installed it unless you have a set of manifold gauges and a 5/16" female quick coupler x 1/4" male flare adapter to check suction pressure.

 

[Kenta]

I have a 3 year old Daikin setup, slow leak and had to get it topped up then it ran out again. Heads would blink green and I went though getting the codes and it was low refrigerant. HVAC company who installed it fixed it under warranty. Talked to the tech and he said it was the flare nut connections and they have been having problems with the OEM ones. Maybe a trend here?

 

[Mesozoic]

Something I learnt today while experimenting with the system.

Upon a fresh start (breaker reset), the system starts with status code 00 (i.e. no error). I started the system in A/C mode and one of the refrigerant pipes did get a little cold to touch. After running this for about an hour, the compressor fan turns off and the system flags a U0 code (refrigerant shortage). This code remains until I do a breaker reset.

I think the compressor shuts off when it detects a refrigerant shortage.

Exact same behavior here with the same code at startup (00) and ends up shutting off after an hour or so and reports a refrigerant shortage (U0) code with the green LEDs blinking on both indoor coils. My system is brand new and has never actually functioned correctly for more than about 8 hours. HVAC contractor is coming next week to investigate, but it definitely sounds like a common theme.

 

[bazar01]

I bought a one ton Daikin from United refrigeration 3 years ago and installed it myself. It's been trouble free.

 

[scanchain]

I have a 3 year old Daikin setup, slow leak and had to get it topped up then it ran out again. Heads would blink green and I went though getting the codes and it was low refrigerant. HVAC company who installed it fixed it under warranty. Talked to the tech and he said it was the flare nut connections and they have been having problems with the OEM ones. Maybe a trend here?

Interesting. Are these the connections on the compressor or on the blowers?

 

[scanchain]

Nothing you can do really but wait for the warranty service order from the company that installed it unless you have a set of manifold gauges and a 5/16" female quick coupler x 1/4" male flare adapter to check suction pressure.

Thanks. Now waiting for the installer to come out to investigate next week.

 

[Kenta]

Interesting. Are these the connections on the compressor or on the blowers?

These were on the lines coming into (or out of) the outdoor condenser.

 

[Mesozoic]

Contractor came out to service the malfunctioning, brand new Daikin system in my shop. He spent the better part of the day taking care of things, but the root cause of the failure seems to be incorrectly installed plugs on the unused refrigerant ports of the outdoor unit - a refrigerant leak. Seems to be working quite well now.

 

[scanchain]

Contractor came out to service the malfunctioning, brand new Daikin system in my shop. He spent the better part of the day taking care of things, but the root cause of the failure seems to be incorrectly installed plugs on the unused refrigerant ports of the outdoor unit - a refrigerant leak. Seems to be working quite well now.

Good for you. My contractor is dragging his feet on coming out to diagnose the problem, and has been giving me all sorts of excuses. It's been about 10 days since I first contacted him.

 

[Mesozoic]

Good for you. My contractor is dragging his feet on coming out to diagnose the problem, and has been giving me all sorts of excuses. It's been about 10 days since I first contacted him.

Yikes, that is a long time! That would warrant pestering in my book... a daily phone call at the very least. I'm sorry to hear that.

 

[jjrbus]

I have a 3 year old Daikin setup, slow leak and had to get it topped up then it ran out again. Heads would blink green and I went though getting the codes and it was low refrigerant. HVAC company who installed it fixed it under warranty. Talked to the tech and he said it was the flare nut connections and they have been having problems with the OEM ones. Maybe a trend here?

They should not be topping off a mini split, the charge in them is done by weight and is critical for proper operation.

Most mini split issues are from improper installation and I am not seeing reported problems with OEM Daikin flair fittings. I do see quite a few problems reported from flairs improperly done.

https://www.youtube.com
/watch?v=cag7DUHIo0M&list=WL&index=3&t=0s

 

[scanchain]

Good for you. My contractor is dragging his feet on coming out to diagnose the problem, and has been giving me all sorts of excuses. It's been about 10 days since I first contacted him.

I am giving up on getting the contractor to come and diagnose the problem. For two weeks, he's been just saying he is out of town, and he is very vague about when he will be back. I will probably submit a complaint to the state licencing board.

I know this is a long shot -- but any recommendations for a quality HVAC in the north metro Atlanta area? It seems like many HVAC contractors are not interested to service ductless systems.

Anyone went through Home Depot to get HVAC repairs?

 

[SALIV8]

I am giving up on getting the contractor to come and diagnose the problem. For two weeks, he's been just saying he is out of town, and he is very vague about when he will be back. I will probably submit a complaint to the state licencing board.

I know this is a long shot -- but any recommendations for a quality HVAC in the north metro Atlanta area? It seems like many HVAC contractors are not interested to service ductless systems.

Anyone went through Home Depot to get HVAC repairs?

You will get a response if you report that poor business to your states Attorney. It is free and there may be an online portal to file complaints.

Check your local rebates also. I had to use an approved vendor to qualify for my electric rebates and they had a list of contractors. I called many til I found a company I liked. Yours may also have this list.

 

[Mesozoic]

I am giving up on getting the contractor to come and diagnose the problem. For two weeks, he's been just saying he is out of town, and he is very vague about when he will be back. I will probably submit a complaint to the state licencing board.

I know this is a long shot -- but any recommendations for a quality HVAC in the north metro Atlanta area? It seems like many HVAC contractors are not interested to service ductless systems.

Anyone went through Home Depot to get HVAC repairs?

I'd say it's less that they aren't interested in servicing ductless systems, but that they do not have the knowledge required to install/service them. My GC didn't even know what a ductless system was!

 

[dcg9381]

Talked to the tech and he said it was the flare nut connections and they have been having problems with the OEM ones. Maybe a trend here?

More likely the flare at the line set. Low refrigerant should show up on a code test.

There are "flare seals" that you can buy, which I'll be using on my next installs.

 

[scanchain]

More likely the flare at the line set. Low refrigerant should show up on a code test.

There are "flare seals" that you can buy, which I'll be using on my next installs.

Interesting. When you use the flare seals, do you still tighten with the same torque?

 

[scanchain]

This is the OP. I thought I would provide an update.

The contractor who installed my unit claimed that he is winding down his business. Asked me to look for someone else to solve the issue.

I had another contractor come and investigate. He loosened and re-tightened the flare fittings outside, and pressurized with nitrogen @ 400 psi. He came back two days later to find that the the pressure on the suction side is 0. The pressure on the liquid (high) side is good. He then put the suction side into high pressure (600 psi) and tried to listen for gas leaking in the basement but couldn't hear anything. Within half an hour, the suction side leaked down to 300+ psi. Cost me $425.

His suggested next step: solder service valves onto each of the linesets (I have 3), pressurize the linesets to isolate which lineset is bad. Cost $1000.

Thereafter, if one lineset is bad, it will be another $1000 to run a new lineset (buried in the drywall) and re-charge system with R410A. I would be responsible separately to patch back the drywall.

Are these prices in line? At this point, I just feel like ripping out the mini-splits and start over with a central HVAC.

 

[SALIV8]

Im not a pro.

That being said that doesnt sounds right to me at least his terminology. How are the flare connections at the indoor units? He just listened for a leak only? My tech used blue spray to watch for bubbles at each connection.

Also linesets are approx $125-$300 depending on length, insulation, and brand When i was looking. Replacing a lineset should be pretty easy that you could do yourself.

Also there are services valves at the outdoor unit to do what he is saying about brazing in a shrader. I dont think this guy knows what hes doin.

 

[Mesozoic]

Agreed with above, you need to find someone who understands ductless systems - they're common in Asia and Europe, significantly less so in the US.

 

[jjrbus]

I am outraged at the level of HVAC service in Florida! The level of incompetence are to the point of criminal.

I am not an AC tech, just another guy trying to get by but he listened for a leak?? $425 and he "listened" for a leak. Now if he used an ultrasonic detector I would be ok with that. I have never seen an AC tech use an ultrasonic detector to look for a leak. If he was going around listening for a leak I would have told him to leave and refused to pay.

They make professional leak detectors, but would not expect someone charging $95 hour to have a decent tool on their truck. They use the line, that they do not work very well or give false readings. Which can be true, but much better than an ear. I am a handy type homeowner and I have a cheap refrigerant leak detector. 2 cars an RV and 3 mini splits to maintain.


https://www.amazon.com/dp/B0023SMJL0?tag=aclabnew-20

Horrible situation to be in, do not expect anything better with a normal forced air system.

I would try calling Daikin and see if they will recommend someone. They have spent lots of money entering the US market and I am sure they do not want any bad press. You want to find someone at corporate level, not the local distributor.

My opinion and worth what you are paying for it!