Air-con loses effectiveness after time

[sms747]

We got a new mitsubishi just over a year ago, stared to run with warm air not cold. When the guy came to clean it he said the gas level should be 80 but was only 40 so had to top up a lot. I said it must be leaking be he said no it happens if you turn it on and off a lot? How can you actually find if it has a leak?

Edited March 4, 2014 by sms747

[rhinoboy]

Not a very good answer to me. Better get another quote. No way does it change if turns off and on a lot. If that is the case the Capacitor is bad, but sounds fishy to me. Mitsubishi is a great product so most likely a leak, as they didnt insatll it correctly.

[Dellboy218]

Not a very good answer to me. Better get another quote. No way does it change if turns off and on a lot. If that is the case the Capacitor is bad, but sounds fishy to me. Mitsubishi is a great product so most likely a leak, as they didnt insatll it correctly.

The capacitor attached to the motor is to allow a 3 phase motor to run on a single phase, without it the motor would not turn. This is the simplest method. A crude way of telling if there is little gas left in the system is to feel the air off the outside condensing unit. The gas gets really hot when it is compressed so if the air coming off the condenser cooling fan is not 'very' hot you may be short of gas. The original question pose by the OP could be, as Winnie said, icing up. If there is a lot of dirt in the evap fins (the internal unit) this could restrict air flow causing icing, or of course the thermostat could be defective and the compressor runs until such time as icing occurs. as it happens all the time it is not likely to be a gas problem. If dirt in the evap fins is a problem then a service would sort that out.

[rhinoboy]

Thanks for that Dell

[uptheos]

So many tips about having them cleaned/serviced/ topped up etc, for around 500 Baht each.

Any chance of you guys sharing who you use to to this and contact details please?

[sms747]

Unless topping up ours charges 250 baht, but only local where are you?

[khunkeith]

the room air conditioners should have about 68-70 PSI if it uses R-22 coolant. It normal for a coolant top up annually. However, if you need to charge a air conditioner more than once a year or, the top up or more than 10-15 PSI, you have a leak somewhere. The leak migh tbe very small and a leak detector will not find it. I have been going through this for 2 years now. Every 3 months, the PSI in my air conditioner drops from 70PSI down to about 30-40 PSI.

Back in the states, a air conditioner technician will inject a purple dye into the R22 and come back a few days later to look for the leak. I have been trying to find that same dye here in THailand but, no luck yet. Does anyone know about where it can be purchased in Thailand. My air conditioning repairman know about the dye but, said he has never seen it here. But again, I live in the northern Provinces (2 hours from Udon) and often have to travel to Bangkok/Pattaya area to find up to date items.

http://www.tooltopia.com/tracerline-tp8621.aspx

If anyone knows where I can buy the dye and injector kit, please let me know.

THanks

[jonwilly]

Get it serviced.

ALL Engineering devices need servicing on a regular basis, even if, as with many air cons it's just cleaning out of all the accumulated muck.

I have mine done on a yearly basis and it's surprising just how much sh1t is washed out of the system by the flushing water used by the pros.

B500 is what I pay through my condo office.

john

[rhinoboy]

Did you ever get your aircon serviced? We got ours serviced yesterday and they did a great job cleaning and recharging one of the units that they said needed it. The lady in our condo office arranged it. She said to call Yotim at 081 992 0996 but that must be the guy at the company she contacts to arrange appointments.

When the three-man crew showed up, they were wearing shirts that said "Air Sale & Service" in English with the phone number 053 804 673 Nobody on the crew spoke English, but I don't know about the office.

[CobraSnakeNecktie]

There are a few companies who service AC's, with a cost of upto 500Baht, Siam TV to name only

Your issues could be servicing, maybe need a top up of gas etc

I have had my A/C serviced by Siam TV a few times and they bring a tank with them but they never seem to top up my unit.

When I ask them about the gas level they say it's okay but I kind of think they (siam tv mgmt) might have a slight profit motive to reduce costs.

The A/C seems pretty good but not quite like new. Is it possible its less than full but not below a threshold they feel obligated to refill?

Any opinions to offer?

[Thighlander]

refilling a leaking a/c unit is usually good for a week or two.

This company sells leak detector liquids in Bangkok. http://www.swagelok.com/bangkok

[northernjohn]

"Servicing" air cons smells like a scam to me. There really are no parts that need 'servicing'....whatever that means..

Replacing or repairing ...maybe....but there is no ability to 'service' a closed system a/c unit.

The compressor fins can be hosed out and dust eliminated that way....gassing should only be an issue if there is a leak...and there shouldn't be a leak.

The compressor is not mean to work constantly...it is meant to turn off and on...

The service is just a cleaning. I use my AC all the time and have them come out about twice a year. For the inside condenser/fan parts they take all the plastic casings off and enclose the condenser fins in plastic bags, then use a pressure washer to clean out the fins, collecting the wastewater in a large bucket. They use the same pressure washer to blow out the outside compressor units as well. Then they put everything back together and cleanup. There is a definite improvement in cooling and airflow when they finish. Well worth it for 400b/unit, in my opinion.

I believe you hit the nail on the head with twice a year. I have heard recommendations of 3 times a year.

[ThaiHerbs]

^ It gets pretty grubby inside.. all parts that touch the air the flows through it will get very dusty and dirty, even when using filters. So service is mostly cleaning the thing out completely, and checking if the filters need changing and the gas topping up.

We have 2 airconditioners. One small old one is only used occsionally (spare bdrm/ironing room) and a new one purchased 2 years ago for the master bdrm. Last year we had them serviced, they only cleaned filters and checked fluids. This year Noi contacted another company she knows and the owner came alone,

he tore apart the new one and showed us all the dirt accumulated everywhere, not just on the filters. He spent 2-3 hrs dismanteling/cleaning. Works perfect. This air con used to pump out a lot of water outside, now it doesn't??? and works perfect. I thought all air cons kick out some water???

With the old one he replaced a part (looks like a glass tube?) and did a basic cleaning. Works perfect now, was not cooling well before. Forget the cost, around 1,000B total or just a bit more, forget.

If interested call Noi at the store for the name & phone of the guy www.thai-herbs-chiangmai.com/contact.php he only speaks Thai, Noi knows a fair bit of english but perhaps your Thai wife/gf would get better info.

We were really happy with the guy.

Doug

[Thighlander]

I thought this was an interesting piece: http://www.qwik.com/education-and-training/articles/DontTreatTodayRefrigwithYestTech/

[LedZepp5]

I have the same problem as OP; my AC isn't putting any cold air anymore. It's effectively just a fan now. Anyone have the number of a repairman in Chiang Mai?

[khunkeith]

I have stayed in hotels, both in resort and no resort areas and Thailand and they have the same room airconditioners I have at home. Only one time have I turned on the AC in a hotel room that did not work, most times, they cool the room down very quickly. I am sure that most hotel owners don't do regular service on the air conditioners in the rooms (on more than one occasion, I have removed the filter, incrusted with dust and debris and cleaned it to get a better air flow and cleaner air. I have a mold and mildew allergy). From the looks of the air conditioners in many hotels, they are many years old as well and, brands are all over the map.

We have a 3 room house and a room air conditioner in each room. 2 years ago, we replaced that Thai windows with thermal windows to prevent air leaking. That made a huge inprovement but, still, if I want to go to bed at 11PM, I have to turn on the AC at 8PM as it takes about 3 hours to cool down the room. In hotels I have stayed in, it usually takes about 15-30 minutes I would guess. I do understand that the ambient temperature of, not only the air must be cooled down but, objects in the room as well. If the air temperature is 35C, then the objects in the room in the room (bed dresser, walls, floor, etc) are also 35C and must cool down as well or they radiate heat. I have compared BTU's with units in hotels to my home units and with square meters in the rooms at home and in hotels and they seem to be about the same.

So, why is it that hotel units seem to work better than home units? Are they commercial grade AC units v home units? My wife and I went to a kitchen appliance store that specialized in commercial grade appliances for restaurants and hotels (toaster, coffee pots, deep friers, etc) and they were much better made (but 3 times the cost) than what we have bought at the Big C or Lotus. Does anyone have friends or contacts that own or manage hotels and ask them if they buy the same sort of AC units most of us purchase or, do they purchase a high grade that has a lower maintance requirement?

Thanks

[khunkeith]

update to my AC problem. The AC man was just at my house and checked the coolant level and it was down a little since it was charged 2 weeks ago but, not enough to make a big difference in the operation. However, he did mention that, because the outdoor part is in the sun, the heat makes the coolant expand and, gives a high reading than what it actually is. Amazing. He is coming back again tomorrow in the morning to check before the sun beats down on it and says it will be a more accurate reading.

When I asked him about hotels and why the AC units there work so much better, he said was because there is usually a floor above or, insulation used in the roof. I did not think about that. When we built the house, we did not have insulation installed in the attic. Tomorrow, I am on a quest to find someone to install insulation. I am not crawling around in my attic when it's damn near 100F outside, it's probably 125F in the attic.

will update after the collant is checked tomorrow morning to see if the reading is different from today.

[Thighlander]

It's very common for the condensing unit to be in the sun. Often times they are on flat roofs. It's more important for the blower to be completely unobstructed. The general rule on btus for Thailand is 600 btu psm, but that can be complicated by western exposure, a high ceiling, or an extremely hot attic.