Mitsubishi Aircon - My remote is set to 30C but the room temp is 25C ????

[Pumpuynarak]

I have the remote set at 30C in an attempt to increase the room temp but it persists in only achieving 25C max.

Anyone have a clue why ? TIA

[Mavideol]

had similar problem  and decided to change the batteries on the remote, problem fixed for me, hope it works for you as well

[Crossy]

Are you actually trying to warm the room above outside ambient? If so does your A/C have "heat" mode.

 

If it's stuck cooling when you don't want it to do try new remote batteries as above, then try turning it off at the breaker, have a coffee/beer, then try it again.

 

Right now opening the windows would achieve what you want at zero cost.

 

[Excel]

You mention your remote is set to 30 yet your a/c achieves 25 How did you check the actual temperature ? You often find that the temp sensors have a mind of there own and whilst your remote sends a signal to the sensor if it is in the main unit ( some sensors are in the remote ) , the sensor could be faulty or perhaps have a coating of dust if it is in the main unit or perhaps, if in the remote, the remote is in a warmer place.

[couchpotato]

1 minute ago, Crossy said:

Are you actually trying to warm the room? If so does your A/C have "heat" mode.

 

Right now opening the windows would achieve what you want at zero cost.

 

Exactly--u beat me too it.

Aircons cool, not heat. And if u are in Thailand very doubtful there would be a heat mode/pump on your unit.

As suggested, turn off the aircon, and the temp will rise quickly.

[Excel]

7 minutes ago, couchpotato said:

Exactly--u beat me too it.

Aircons cool, not heat. And if u are in Thailand very doubtful there would be a heat mode/pump on your unit.

As suggested, turn off the aircon, and the temp will rise quickly.

So will the humidity

[Pumpuynarak]

17 minutes ago, Mavideol said:

had similar problem  and decided to change the batteries on the remote, problem fixed for me, hope it works for you as well

I have done the same but still have the problem.

[lopburi3]

The temp sensor is normally above the input fins and almost at ceiling level so hottest place in room.  Is your ceiling insulated?  If not that can be a real issue and might require AC unit to be hung lower on wall or run dry mode rather than cooling when sun is hot on the roof.

Edited May 29, 2022 by lopburi3

[Pawpcorn]

Sometimes thermal sensor will fail in the wall unit.

 

I had irratic temperatures in my Mr.Slim a year ago... I found image samples of A/C thermal sensors on Lazada... showed these to my repair guy, INSISTING that he install a new thermal sensor...which he ordered, and installed, and problem was resolved.

 

Requested temperature on the remote, was once again delivered to the room.

[Pumpuynarak]

18 minutes ago, Crossy said:

Are you actually trying to warm the room above outside ambient? If so does your A/C have "heat" mode.

 

If it's stuck cooling when you don't want it to do try new remote batteries as above, then try turning it off at the breaker, have a coffee/beer, then try it again.

 

Right now opening the windows would achieve what you want at zero cost.

 

Trouble i'm having is the room is too cold at 25C so i thought setting the remote to 30C (max) would increase the temp but that is not happening. I'm using a thermometer to check what the actual temp is in the room.

I've changed the remote batteries and even bought a new remote, all to no avail.

The temperature without using the aircon is currently 33C outside and 29C in the room but as soon as i put the aircon on set at 30C the room temp goes to 25C.

Yes i do have HEAT mode but i'm trying to cool the room down but not to the 25C i'm achieving.

 

I hope that makes sense.

[Crossy]

1 minute ago, Pumpuynarak said:

The temperature without using the aircon is currently 33C outside and 29C in the room but as soon as i put the aircon on set at 30C the room temp goes to 25C.

 

So it's cooling to lower than the set temperature? 

 

Try the power off at the breaker trick and new batteries in the remote.

 

Then it's time to check that the temperature sensor is clean and actually functional (could be time to get the A/C man in).

[Pumpuynarak]

31 minutes ago, Excel said:

You mention your remote is set to 30 yet your a/c achieves 25 How did you check the actual temperature ? You often find that the temp sensors have a mind of there own and whilst your remote sends a signal to the sensor if it is in the main unit ( some sensors are in the remote ) , the sensor could be faulty or perhaps have a coating of dust if it is in the main unit or perhaps, if in the remote, the remote is in a warmer place.

I use a thermometer. I'm thinking the sensor must be faulty.

[Pumpuynarak]

15 minutes ago, lopburi3 said:

The temp sensor is normally above the input fins and almost at ceiling level so hottest place in room.  Is your ceiling insulated?  If not that can be a real issue and might require AC unit to be hung lower on wall or run dry mode rather than cooling when sun is hot on the roof.

Ceiling is insulated, i'll try running in "dry mode".

[Pumpuynarak]

8 minutes ago, Crossy said:

 

So it's cooling to lower than the set temperature? 

 

Try the power off at the breaker trick and new batteries in the remote.

 

Then it's time to check that the temperature sensor is clean and actually functional (could be time to get the A/C man in).

Yes its cooling to 25C when the remote is set to 30C, i've just turned the power off at the breaker box and turned on again so will see what happens later when i turn the aircon on.

If i can't remedy the problem i'll get my aircon man round to clean and check that the sensor is actually working.

[bbko]

How far away is the remote from the unit? Too far and it won't work properly.

 

Another thing is buying a new remote cost only 200-300b (cheaper if you go generic).

 

 

https://www.lazada.co.th/catalog/?q=mitsubishi+air+con+remote&_keyori=ss&from=input&spm=a2o4m.searchlist.search.go.4cc96a08sRuuhA

 

[Excel]

20 minutes ago, Pumpuynarak said:

I use a thermometer. I'm thinking the sensor must be faulty.

I would suggest you perform a reset of your unit first to see if that cures your problem. The manual or simply googling with your unit type to find how to do that .

[Will B Good]

Is the Aircon beeping to say it has received the signal.

 

We have LG and the remote changes temp and other settings on its little screen, but if the aircon doesn't beep it doesn't actually change anything.

[Pumpuynarak]

21 minutes ago, bbko said:

How far away is the remote from the unit? Too far and it won't work properly.

 

Another thing is buying a new remote cost only 200-300b (cheaper if you go generic).

 

 

https://www.lazada.co.th/catalog/?q=mitsubishi+air+con+remote&_keyori=ss&from=input&spm=a2o4m.searchlist.search.go.4cc96a08sRuuhA

 

Its circa 20 feet away when being used and i'm using a new remote i purchased 2 days ago. 

[Pumpuynarak]

16 minutes ago, Excel said:

I would suggest you perform a reset of your unit first to see if that cures your problem. The manual or simply googling with your unit type to find how to do that .

A reset of the remote (done) or do you mean the wall unit in which case i'll google as you suggest but i might just let my aircon man do that lol

[Pumpuynarak]

17 minutes ago, Will B Good said:

Is the Aircon beeping to say it has received the signal.

 

We have LG and the remote changes temp and other settings on its little screen, but if the aircon doesn't beep it doesn't actually change anything.

Yes its beeping and showing changes on the remote window.

[Excel]

Just now, Pumpuynarak said:

A reset of the remote (done) or do you mean the wall unit in which case i'll google as you suggest but i might just let my aircon man do that lol

Wall/outside unit reset. Wouldn't trust a local aircon man, 90% have no idea how to service an a/c unit correctly. Still suggest you google and get your units manufacturers service manual and read it yourself.

[SomchaiDIY]

If ac always below set temperature possible some service check is required

Some cause of temperature control fault

 

Air flow problem

Sensor off correct position

Sensor thermistor faulty

Incorrect set data from remote

Fault at control circuit

Other heat source near ac

Bugs animal in system

Infrared remote only set temperature they do not control the temperature

 

If battery or battery connection bad ac unit can reject data from remote and go on default setting

 

If other remote button like fan speed work ok possible remote is not problem

 

Confirm bleeper sound from many indoor box show good data sent when remote button pressed

 

[couchpotato]

1 hour ago, Pumpuynarak said:

Trouble i'm having is the room is too cold at 25C so i thought setting the remote to 30C (max) would increase the temp but that is not happening. I'm using a thermometer to check what the actual temp is in the room.

I've changed the remote batteries and even bought a new remote, all to no avail.

The temperature without using the aircon is currently 33C outside and 29C in the room but as soon as i put the aircon on set at 30C the room temp goes to 25C.

Yes i do have HEAT mode but i'm trying to cool the room down but not to the 25C i'm achieving.

 

I hope that makes sense.

You are describing exactly what an aircon is supposed to do--ie: cool.

If the room is at 29C without the aircon on, then how do expect the room to get warmer when you turn the aircon on....be sensible here.

 

As someone else suggested, try other settings such  as Fan, Dry etc and experiment to get your humidity down.

 

But my last suggestion is to buy a portable dehumidifier, and do not use the aircon. This will bring down the room humidity within 24 hours and then just use on a timer.

[OneMoreFarang]

Most AC remote controls send a one way signal. It is send from the remote to the AC. Maybe it arrives and maybe it arrives correctly.

Just the fact that X is shown on your remote doesn't mean your AC is doing X.

[sometimewoodworker]

5 hours ago, couchpotato said:

Exactly--u beat me too it.

Aircons cool, not heat. And if u are in Thailand very doubtful there would be a heat mode/pump on your unit.

As suggested, turn off the aircon, and the temp will rise quickly.

We have 2 AC units, the big cassette only does cooling the other a Mitsubishi move eye has both cooling and heating.
 

You are correct that the majority don’t heating but wrong about the higher end models. Though we seldom use the heating function due to a superbly insulated house.

[treetops]

8 hours ago, OneMoreFarang said:

Most AC remote controls send a one way signal. It is send from the remote to the AC. Maybe it arrives and maybe it arrives correctly.

Just the fact that X is shown on your remote doesn't mean your AC is doing X.

OP already comfirmed the aircon unit was bleeping, thus indicating the instruction has arrived and been understood.

[The Hammer2021]

30° Is not cool- its hot! LOL

 

[Pumpuynarak]

19 hours ago, lopburi3 said:

The temp sensor is normally above the input fins and almost at ceiling level so hottest place in room.  Is your ceiling insulated?  If not that can be a real issue and might require AC unit to be hung lower on wall or run dry mode rather than cooling when sun is hot on the roof.

 

19 hours ago, Pumpuynarak said:

Ceiling is insulated, i'll try running in "dry mode".

Well i tried using the "dry" mode and its much better. Instead of achieving 25C when set at 30C its now achieving 27/28C which is ok for me as i find that temp not too cold.

 

Thanks for all your help guys, i appreciate. When next getting my aircon guy round for servicing/cleaning i'll mention it to him and maybe get him to change the sensor in the indoor wall unit.

[digbeth]

Unless you are in the north of Thailand, most aircon in Thailand has the heat mode 'reverse-heat pump' disabled and not plumbed for the external condensor to be cooled and have the condensate goes somewhere 

 

try the fan only mode if you're too cold

[Mavideol]

forgot to tell you on my previous post that I had to replace the thermostat as well. Originally changed the batteries on the remote, it worked for maybe 1 week or so but it happen again, I open the front cover on the unit and on the right side about the indicator lights there is a temperature sensor, mine was not working as I warm it up to see if would start, nothing happen then I call the repair man, he came tested it, determined it was not working, replace it and decided to service the unit, all together charged me 450 baht and all was back working