No matter how low I set thermostat aircon won't get below 29

[giddyup]

I just had the aircon serviced and they replaced something that looks like a coil in a car. However, no matter what I set the remote to (say 23 degrees) the room temperature won't get below 29 degrees. That still feels quite cool, especially when you come in from outside, but I'm curious as to why it won't get any cooler.

[HooHaa]

the numbers showing on a thermostat, especially the old dial thermostat are largely arbitrary.

there is also the possibility that the unit is under powered for the room or season, or both.

[giddyup]

the numbers showing on a thermostat, especially the old dial thermostat are largely arbitrary.

there is also the possibility that the unit is under powered for the room or season, or both.

The aircon (Samsung) is probably about 7 years old, and it's the remote that has the temp. settings.

[daveAustin]

Low on gas?

[lopburi3]

When you set to 23 is the compressor staying on? If you can not check is the air still cool coming out of unit?

It is currently the hot season and if sun on unit or roof even more of an issue if unit is small size for the area needing cooling.

[giddyup]

When you set to 23 is the compressor staying on? If you can not check is the air still cool coming out of unit?

It is currently the hot season and if sun on unit or roof even more of an issue if unit is small size for the area needing cooling.

The aircon is 12,000 BTU, and the room isn't huge, probably 5 X 6 metres. The aircon does switch off when around 29-30 degrees is reaches, but only if I set the remote to around 27, not if I set it for 23. the aircon itself doesn't get sun, but the side windows of the bedroom get a fair bit.

[petermik]

It aint big enough giddyup sorry..............

[giddyup]

It aint big enough giddyup sorry..............

Am I supposed to take your word for that, or do you have some information that backs up your statement? According to a Google search, a 12,000 BTU aircon will service between 450-550 square feet. My bedroom is nowhere like that big.

The most common window air conditioning units come in cooling capacities ranging from 5,000 to 12,000 Btu. A 12,000 Btu air conditioner can cool between 450 and 550 square feet of floor space. A 12,000 Btu unit could cool a room 25 feet long by 20 feet wide that has 500 square feet of floor area. Manufacturers give their own ratings as to how much room area they believe their units can cool.

[lemonjelly]

Was it doing this before it was "serviced" ?

[giddyup]

Was it doing this before it was "serviced" ?

Actually just prior to service it was blowing too cold, and then the next day there was no cold air, that's when I called in the "experts" for a service.

[giddyup]

Thermostat...

I'm suspecting that as well.

[Crossy]

Off topic posts and replied deleted.

[wherma22]

It aint big enough giddyup sorry..............

Am I supposed to take your word for that, or do you have some information that backs up your statement? According to a Google search, a 12,000 BTU aircon will service between 450-550 square feet. My bedroom is nowhere like that big.

The most common window air conditioning units come in cooling capacities ranging from 5,000 to 12,000 Btu. A 12,000 Btu air conditioner can cool between 450 and 550 square feet of floor space. A 12,000 Btu unit could cool a room 25 feet long by 20 feet wide that has 500 square feet of floor area. Manufacturers give their own ratings as to how much room area they believe their units can cool.

I had a similar problem with my aircon. My room is around the same size as yours, 5x5m. Aircon is old, around 10 years. 12000btu is more then enough for a room that size. We had the same problem, aircon didnt go below 29°, first technician came to fill with gas, but it didn't help. He advised us then we should change the aircon because it was too old and there was nothing he could do to fix it. Gf was ready to go buy a new aircon, but i wanted to get some advice from another technician first. In the end i did good as the other technician fixed the problem by changing the old tubes with new copper ones. The problem was that the old cable had holes in it and wasn't protected correctly. Since then the aircon works perfectly. And the electricity bill went down a little as well. Hope it helps!

[ttthailand]

Maybe it needs a good cleaning of all the coils, fan and filters. Just cleaning the pull out filter is not enough you need to clean everything. I had a similar problem and a good clean made a huge difference.

[giddyup]

Maybe it needs a good cleaning of all the coils, fan and filters. Just cleaning the pull out filter is not enough you need to clean everything. I had a similar problem and a good clean made a huge difference.

All been done.

[IMHO]

It aint big enough giddyup sorry..............

Right, with days reaching 40c, there's not much chance of just 12,000 BTU in a 30sqm room coping well.

According to Daikin, 18,000 BTU is where it starts for this size room: http://www.daikin.co.th/service-btu-calculation/

According to my own experience in a similar sized room (5.5 x 6.0M), with a few heat sources, a dormer section (5M high), but no direct sunlight, 24,000 BTU isn't even enough on a 40c day. I recently upgraded that one to 33,000 BTU, which does the job - but even so, can still only get the room to 23c when it's 40c outside.

[ttthailand]

Did the unit cool the room in past years ? How was it last summer ?

[giddyup]

It aint big enough giddyup sorry..............

Right, with days reaching 40c, there's not much chance of just 12,000 BTU in a 30sqm room coping well.

According to Daikin, 18,000 BTU is where it starts for this size room: http://www.daikin.co.th/service-btu-calculation/

According to my own experience in a similar sized room (5.5 x 6.0M), with a few heat sources, a dormer section (5M high), but no direct sunlight, 24,000 BTU isn't even enough on a 40c day. I recently upgraded that one to 33,000 BTU, which does the job - but even so, can still only get the room to 23c when it's 40c outside.

The little research I did showed that a 12,000 BTU aircon would service a 450-550 sq. foot room. My room is approx. 5 x 4 metres = 20 sq. metres = 215 square feet, or less than half of what the aircon is capable of cooling.

[ttthailand]

Can you hear the compressor turn on ? It is sounding like only the fan is working. Check your settings to make sure the aircon is selected and not just the fan. Also have someone switch the control to 30 and then wait for 5 minutes and then switch to 20 degrees while you are outside at the heat exchanger. You should hear the compressor kick in.

[PoorSucker]

I had a Samsung that had some issues.

Finally I found an advice on the net that worked for me.

Turn of the electricity to the unit totally for 30 min, it alloess the eprom to drain all the power and reboot in original mode.

Helped for me.

[giddyup]

I think I'll just get the "experts" back tomorrow to check it out again. Thanks for all the advice though.

[IMHO]

It aint big enough giddyup sorry..............

Right, with days reaching 40c, there's not much chance of just 12,000 BTU in a 30sqm room coping well.

According to Daikin, 18,000 BTU is where it starts for this size room: http://www.daikin.co.th/service-btu-calculation/

According to my own experience in a similar sized room (5.5 x 6.0M), with a few heat sources, a dormer section (5M high), but no direct sunlight, 24,000 BTU isn't even enough on a 40c day. I recently upgraded that one to 33,000 BTU, which does the job - but even so, can still only get the room to 23c when it's 40c outside.

The little research I did showed that a 12,000 BTU aircon would service a 450-550 sq. foot room. My room is approx. 5 x 4 metres = 20 sq. metres = 215 square feet, or less than half of what the aircon is capable of cooling.

Oh, your room is smaller now? Before it was 5x6 There's only 50% difference between 5x4 and 5x6

I linked you to a calculator from the most respected brand in the business, which makes recommendations based on Thai conditions. Select the options that apply to the room you're cooling, and you can be sure they'll spec a unit that will give you the 15-16 degree deltas you're probably looking for.

[SOUTHERNSTAR]

Maybe its a female ac, so put up the temp and maybe it becomes cooler.

[Tywais]

If they replaced a 'coil' (condenser coil?) then perhaps they discharged the gas and perhaps not topped off enough or not closing the seal enough.

On the other hand, there also may be a coil that is the temperature sensor inside the interior unit itself that monitors the a/c real temperature against the set point. Perhaps they messed up somewhere with that as you indicate the behavior changed.

[cat handler]

Clean the filter, or thermostat or gas.....but sounds like Thermo....easy to replace and usually cheap-1000baht or so.

[Shiver]

I'm no expert, but these personal evaporative coolers look like they might be useful. Claims it can get to 17C and use 10W power (I haven't tried them). Better to cool yourselves than the whole room though if they work:

https://www.indiegogo.com/projects/world-s-first-personal-air-conditioner#/

(There are other approaches than just this one).

[Pib]

OP,

Your 12K BTU is plenty big enough for your room...I have a 8K BTU in a room your size and it cools it down just fine after about 10 minutes but I will admit I have it set to only pull down to 25C.

Also wish you could better describe "they replaced something that looks like a coil in a car." When I read that I thought "did they replaced the entire evaporator/inside cooling fins & coils?" Probably not because that would be big money...would requiring the ordering for the fins/coils, major job....they would just instead say replace the whole A/C. But maybe you were talking a "thermostat?" But usually a thermostat is just a straight looking short tube.

Also, you said they cleaned the unit. Does that include the "outside unit called the condensor/compressor? If the outside unit fins/coils are too dirty it can degrade cooling performance a lot and cause much higher electric bills.

Also how and where are you measuring the room temperature? Some kind of thermometer hanging on the wall, in a digital clock, etc? You can have "wide variations" of temperature within a room. Remember your A/C is measuring the temperature at one location only and that location is a temperature probe most likely mounted on the inside cooling unit fins/coils...just behind the filter you change. It's basically measuring the air that is returning to the inside unit to be pushed through the cooling fins/coils again, cooled down again, and pushed back out into the room.

Pulling down to 23C in this HOT weather could be challenge/take a while. Also is the outside unit/condenser/compressor always running in attempting to pull down to 23C...I expect it would be in this daytime hot weather. If it's not running close to 100% then maybe you just have a temperature measuring problem.

[weedywhaoo]

The standard formula to calculate btu here is; area sqm × 800= necessary btu needed. This is for a normal room. In your case

30×800=24000 btu. I would say you need a larger ac.

[TheCruncher]

It aint big enough giddyup sorry..............

Right, with days reaching 40c, there's not much chance of just 12,000 BTU in a 30sqm room coping well.

According to Daikin, 18,000 BTU is where it starts for this size room: http://www.daikin.co.th/service-btu-calculation/

According to my own experience in a similar sized room (5.5 x 6.0M), with a few heat sources, a dormer section (5M high), but no direct sunlight, 24,000 BTU isn't even enough on a 40c day. I recently upgraded that one to 33,000 BTU, which does the job - but even so, can still only get the room to 23c when it's 40c outside.

The little research I did showed that a 12,000 BTU aircon would service a 450-550 sq. foot room. My room is approx. 5 x 4 metres = 20 sq. metres = 215 square feet, or less than half of what the aircon is capable of cooling.

Your room must have shrunken in the laundry, because a few posts ago it was still 5 x 6 = 30m²

[Gerard052]

When you set to 23 is the compressor staying on? If you can not check is the air still cool coming out of unit?

It is currently the hot season and if sun on unit or roof even more of an issue if unit is small size for the area needing cooling.

The aircon is 12,000 BTU, and the room isn't huge, probably 5 X 6 metres. The aircon does switch off when around 29-30 degrees is reaches, but only if I set the remote to around 27, not if I set it for 23. the aircon itself doesn't get sun, but the side windows of the bedroom get a fair bit.

I just bought an aircon 2 weeks ago and they told me that a 12,000 BTU is good for 4 x 4 metres and yours is 5 x 6 metres which is much bigger, also did they check the freon gas? After all it is a 7 year old unit and the freon gas should be checked every 1-2 years. Maybe that's where the problem lies coupled with your big space. Let us know how you make out. Cheers.