Airconditioner Technicians

[Naam]

My understanding was that the air intake took place at the outdoor unit...

goodness gracious JBrain!

...however in a house with rooms next to each other I would think that the ambient temperature is close in both rooms.

remember the meeting room attached to my study where we sampled a 37 year old Port? it's window is to the west and it has two outside walls, the longer wall west. on both sun from 13.00 till the sun goes down.

the adjacent room is a guest room, window and one outside wall north; on both never sun. without airconditioning in any of these two rooms the temperature difference would be at least 3ºC.

[rosst]

There are a couple of issues, I have not seen any reference to gas pressures, have they connected their gauges and taken high pressure and low pressures? This is a first and crucial initial test of the charge and also the compressor operation??

The poster who advised the pipe temperature checking is on the right track, but the technicians should be able to generate a maximum cool setting to check the function of both units which then limits the potential fault to a control fault.

Did you PM the guy who chimed in with working for D for ten years, sounds helpful??

The "sensor" is probably a negative coefficient thermistor which if open circuit would tend to tell the unit the air was too cold which should reduce the "effort" from the compressor leading to a rise in temperature.

The usual manner of temperature control is to increase or decrease the refrigerant "effort" by slowing the motor or reducing the stroke of the compressor to stop it turning on and off thus saving energy. I am not sure which method D uses but try turning the temperature up and down and listen to the response from the outside unit of the one which is functioning correctly and then do a comparison with the other unit. Good luck with that.

[jbrain]

The more comments I read the more upset I get, as it seems that these technicians, however being with 5 had no idea of what they were looking for. Or had a perfect idea and just wanted to cover up things.

Yes they have connected their gauges, and however I couldn't read the the scale due to height, I could notice that at all times the arrow stayed in the " blue zone".

On the reports are some MPA measurement which are 0,8 - 0,9 and 7,5 PSI respectively. No idea what they mean.

What I noticed is that during the first 2 tests the arrow would start at the top end of the blue zone, then slowly fall back to around the middle of it. When the last test was conducted with the new PCB installed, the arrow was at the ultimate lower end of the blue zone, any further and it would be in the red zone.That probably also explains the 0,75 PSI reading in the last test result.

Someone can explain to me about those readings, as I'm now thinking they released some refrigerant for some reason. During the last 2 tests at all time 3 people stayed at the outdoor unit while the other 2 and me were inside.

At tests were conducted with the temperature setting to the lowest possible ( 18 degree ) and in the first 2 test I could see that the temperature at the indoor air outlet would reach 18 degree in he first 15-20 minutes then very slowly decrease to around 15 degree and then stay there.

In the last test with the new PCB, the temperature reading would decrease at a constant rate to 8,5 degree, same as it did later that day when I did the the original PCB re-fitted.

I was told by the technicians that with a setting of below 25 degree the outdoor unit will have variable speed but actually never stop running, while with a setting at a higher temperature the outside unit will stop and start again., and that is also what I have noticed.

With my test overnight with the setting at 26 degree I could notice that once the desired room temperature is reached, the air temperature at the indoor unit will fluctuate between 18 and 24 degree. I can also notice that this matches with the switching on and off from the outdoor unit.

During the second test session I have asked them to measure the temperature difference between the suction and pressure pipe, but however the cover of the indoor unit was removed already, they refused to take those measurements.

The question was forwarded to them by a Thai person, so it can't have been a case of not understanding.

[Naam]

With my test overnight with the setting at 26 degree I could notice that once the desired room temperature is reached, the air temperature at the indoor unit will fluctuate between 18 and 24 degree. I can also notice that this matches with the switching on and off from the outdoor unit.

was the room temperate stable at 26º inspite of these fluctuations?

[jbrain]

With my test overnight with the setting at 26 degree I could notice that once the desired room temperature is reached, the air temperature at the indoor unit will fluctuate between 18 and 24 degree. I can also notice that this matches with the switching on and off from the outdoor unit.

was the room temperate stable at 26º inspite of these fluctuations?

If you know of an airconditioner that can keep a room stable at any particular temperature, please forward the details.

As already mentioned in post #24 the room temperature fluctuated between 26 and 27,2 degree at which point the unit starts to blow cooler air until the room reaches 26 degrees.

As said before also, at a setting above 24 degree the outdoor unit is supposed to switch off at intervals, while at a setting below 24 degree the outdoor unit never switches completely off but will control the speed. Probably that will give a more constant temperature, but I have no knowledge about that.

Edited September 16, 2013 by jbrain

[Naam]

If you know of an airconditioner that can keep a room stable at any particular temperature, please forward the details.

thousands of specially designed systems exist which keep rooms (e.g. a laboratories) at stable ±0.1ºC, it's just a matter of money if you would like to have one installed.

[Naam]

As said before also, at a setting above 24 degree the outdoor unit is supposed to switch off at intervals, while at a setting below 24 degree the outdoor unit never switches completely off but will control the speed. Probably that will give a more constant temperature, but I have no knowledge about that.

if an inverter unit switches on/off at a setting of >24ºC means from a technical point of view "useless enginering" seen because >24º falls within the range any aircon is most of the time used. the reason why is to save energy and add a little to the (mostly fictitious) "SEER" rating some manufacturers are boasting about (energy efficiency drops at very low compressor speeds).

[jbrain]

As said before also, at a setting above 24 degree the outdoor unit is supposed to switch off at intervals, while at a setting below 24 degree the outdoor unit never switches completely off but will control the speed. Probably that will give a more constant temperature, but I have no knowledge about that.

if an inverter unit switches on/off at a setting of >24ºC means from a technical point of view "useless enginering" seen because >24º falls within the range any aircon is most of the time used. the reason why is to save energy and add a little to the (mostly fictitious) "SEER" rating some manufacturers are boasting about (energy efficiency drops at very low compressor speeds).

I'm aware of that, but I googled for it and it seems to be normal. However all the results I found concerned aircons of the brand this thread is about.

[buddy]

I'm looking for an inverter aircon myself. Checked the aircon shop at Nongprue intersection and they gave me the well researched answer that they are "more expensive".

Can anyone recommend an aircon shop that carries such aircons AND is able to install AND maintain them?

I have been recommended the D brand as the best since sliced bread. Now I read here that they are probably not that good. Any brand recommendations? The aircon is for a warehouse so I don't really care about noise etc.

if the aircon is for a warehouse with most probably a continous even demand of cooling capacity why would you select an inverter unit?

inverters work only economically if the demand varies a lot. if that is not the case an inverter equals wasted initial investment and with time exponentially higher repair cost.

If for a warehouse application your supposition that an even demand of cooling makes inverters more economical does not make sense.

Lets assume the warehouse does not have insulated panelling it will have large heat ingress especially if the doors are frequently opened by employees.

Inverters are proven energy saving technology and wether even demand or high cooling demand in a warmer climate like Thailand will definitely offer energy savings over a conventional "on off" cycling compressor especially if a larger system like a VRV system is required which might be the case with a ware house.

More here for those that are interested - http://www.daikin.com/global_ac/products/residential/dcinv/outline.html

[Naam]

I'm looking for an inverter aircon myself. Checked the aircon shop at Nongprue intersection and they gave me the well researched answer that they are "more expensive".

Can anyone recommend an aircon shop that carries such aircons AND is able to install AND maintain them?

I have been recommended the D brand as the best since sliced bread. Now I read here that they are probably not that good. Any brand recommendations? The aircon is for a warehouse so I don't really care about noise etc.

if the aircon is for a warehouse with most probably a continous even demand of cooling capacity why would you select an inverter unit?

inverters work only economically if the demand varies a lot. if that is not the case an inverter equals wasted initial investment and with time exponentially higher repair cost.

If for a warehouse application your supposition that an even demand of cooling makes inverters more economical does not make sense.

Lets assume the warehouse does not have insulated panelling it will have large heat ingress especially if the doors are frequently opened by employees.

Inverters are proven energy saving technology and wether even demand or high cooling demand in a warmer climate like Thailand will definitely offer energy savings over a conventional "on off" cycling compressor especially if a larger system like a VRV system is required which might be the case with a ware house.

More here for those that are interested - http://www.daikin.com/global_ac/products/residential/dcinv/outline.html

i happen to know what kind of "ware" the OP stores in his warehouse and i bet my [not so] sweet butt that the area has an excellent insulation to buffer any changes in ambient temperature and heat transfer.

[jbrain]

Yesterday the D..... technicians called that they wanted to come install the new PCB. Told them that the problem seems fixed now, and that I don't need the new sensor.

So I did a quick test in the morning and took pictures with date and time from the thermometer along the process. With the aircon at setting 18 degree and the fan on automatic I measured the following temperatures at the exit of the indoor unit. (minutes/temperature) 5/15 - 13/12,2 - 19/9 - 23/8,4 - 31/7,3 , then went to do something else for half an hour and when I returned the blow out was steady at 6,7 degree.

So went to the office, where I of course was presented with a bill for PCB and labor, but showed them the pictures of the test.

A senior technician had a lot of talk with them and as a result they want to come back and do one more test.

Any chance they gonna perform a test that indicates I definitely need that new PCB ?

Edited September 19, 2013 by jbrain

[Naam]

they want to come back and do one more test

to entertain you in case you are bored

[jbrain]

they want to come back and do one more test

to entertain you in case you are bored

I'm gonna inform them that from now on it's me who charges for wasting my time.

[jbrain]

Being a nearly ten year employee of the D brand im surprised, sorry and disapointed by this outcome for you. I'll be at head office next week and if you would like me to take this up with them then pm me your details and i will have them look into it and the techs who came out to check your unit.

yeah...we would like to hear about the outcome indeed! This is what community fora are there for!

Well I have some update.

Last week the technicians came around a third time to do tests and their final judgement was that the temperature sensor is faulty, so they installed the new PCB once again.

I asked why they can't replace the sensor only as it are clearly two separate parts, which they also admit, but they say their company sells it as a set only. price 2540 + 800 Baht transport and labor cost +vat = 3573 Baht.

They installed and presented the bill. No way jose I was gonna pay that .

Since i was communicating with TV member JohnnyQuid already since the 14th, and he was gonna take it up with the head office as he seemed to have some influence there, I wanted to delay the payment until I got an answer from Johnny. They agreed that I could test it for a week and pay it on today.

There have been several messages between me and JohnnyQuid already during the past 17 days, but until today he hasn't been able yet to even have a talk with anyone in the head office. First when he arrived at the head office in Bangkok on the 18th , every one had left for a meeting in Japan, and last week when they had returned nobody replied to his emails .

I wanted to take the case up with the consumer protection at first, but couldn't really bother for a measly 3500 Baht, so went there today to pay my bill.

When I asked them again why they couldn't replace the sensor only they gave me the same answer as before, it's only available as a complete set.

So I decided to blatantly lie to them, as I have such a feeling that this is common practice in this country, and told them that the Australian branch had told me that the sensor was available as a single part.

Within 5 minutes their story changed and now it was that the part previously wasn't available, but now they had stock.

Price 550 Baht instead of 2540 Baht.

Next week they gonna show up again, remove the PCB unit they installed last week, install my original PCB and replace the sensor or as they call it " mini PCB" .Total price including labor, transport and vat = 1433 Baht. A reduction of 2340 Baht because I could nail them as they were professedly lying for 2 weeks in row.

I hope everyone takes a lesson from this before they order an aircon of the D..., brand in the future,

Now I'm not sure if I should take this any further or maybe don't allow them access again and tell them to climb in a tree .

Edited October 1, 2013 by Rimmer
Libel

[Gavlar1981]

I am looking for some air cons or my new factory office space, any recommendations for the pattaya area, i usually use numchai at the end of Soi Siam. Also do we recommend an air con with inverter???

[jbrain]

So today the technicians came around again, to spend another 5 hours checking things out with 5 technicians. Two who are monitoring the inside temperatures and three who have some appliances attached to the outdoor unit and are monitoring that part.

As i said they had left the completely new PCB inside the unit for the past 2 weeks.

Where i previously would set the aircon at night to 26 degree, I had these days the setting at 27 degree because the outside temperature was lower for the past few days, which would result in a room temperature in the morning at 10pm after running all night of between 25.3 and 26.4 degree depending if the compressor was running or not at the time of checking.

Quite low for a 27 degree setting I would say.

Today they started the test cycle with installing the original PCB with a new temperature sensor attached. Remote set to 25 degree. Ambient temperature at the unit air intake before start at 27.8 degree.

After running for half an hour the indoor unit would blow a constant air of 15.5 degree, but the temperature at the sensor would never reach below 26 degree. Even after running for another hour it would read at the sensor the same temperature.Room temperature would fluctuate between 26.3 and 27 degree.

So room was brought back to ambient temperature, the complete new PCB was installed again and the test repeated with the same settings. Results were the same as with the previous PCB with that difference that the air blown would be closer to 15 degree, but the temperature in the room nor at the sensor would ever reach the desired temperature.

So I suggested to bring the room up to ambient temperature once again and then redo the test with the remote set at 27 degree. This resulted in practical the same temperatures as with the setting at 25 degree.

So once again was reset to 25 degree, everybody left the room and let the aircon run for 1 hour. After returning the room temperature was 25.7 and at the sensor 26.1. Another half hour running and continuous monitoring the temperature in the room and at the sensor didn't bring any change in that.

So even with a complete new PCB and new sensor they could not get a 15 sqm room down to 25 degree from 28 degree ambient temperature.

As said, after 5 hours they have left again and told me that the head office will call me tomorrow to discuss how it will go further.

All by all they have now tested over 20 hours with 5 technicians, replaced several parts over and over, and still can not locate the problem.

To be continued.........................

[Pattaya Pat]

How do you know the exact size of your rooms? Did you measure them?

[jbrain]

How do you know the exact size of your rooms? Did you measure them?

You're trying to be funny ?

[Naam]

How do you know the exact size of your rooms? Did you measure them?

[blackman]

How do you know the exact size of your rooms? Did you measure them?

Lawyer- Before you signed the death certificate, had you taken the pulse ? Pathologist- No. Lawyer- Did you listen to the heart ? Pathologist - No. Lawyer- Did you check for breathing ? Pathologist - No. Lawyer - So, when you signed the death certificate you weren't actually sure he was dead, were you ? Pathologist - Well, let me put it this way. The man's brain was sitting in a jar on my desk. But I guess it's possible he could be out there practicing law somewhere

[Pattaya Pat]

How do you know the exact size of your rooms? Did you measure them?

You're trying to be funny ?

Perish the thought, this is a very serious matter.

It's a genuine question and one I wouldn't mind an answer on.

So again, how do you know the EXACT measurments of your bedrooms etc?

[jbrain]

How do you know the exact size of your rooms? Did you measure them?

You're trying to be funny ?

Perish the thought, this is a very serious matter.

It's a genuine question and one I wouldn't mind an answer on.

So again, how do you know the EXACT measurments of your bedrooms etc?

Does this answer your question ?

[Pattaya Pat]

How do you know the exact size of your rooms? Did you measure them?

You're trying to be funny ?

Perish the thought, this is a very serious matter.

It's a genuine question and one I wouldn't mind an answer on.

So again, how do you know the EXACT measurments of your bedrooms etc?

Does this answer your question ?

There you go, not that hard was it. So you did measure your rooms.

Cheers.

[Naam]

Does this answer your question ?

this tool was made in China JBrain and we can therefore assume it was not produced according to international quality standards. moreover, the question remains what kind of measuring units are shown on this tape.

if it shows Northern Manchurian Centipedes or Guangdong Millisquarewahliters you might have used an incorrect conversion when calculating the area of a room in your home located in Thailand.

please check again and report back. this is a serious matter which could be the reason that your aircon (who's brand can't be mentioned) does not work as expected.

p.s. it could also cause extensive damage to the inverter system of your compressor/condenser unit!

[Pattaya Pat]

I must remember to measure the size of my bedrooms.

[jbrain]

Does this answer your question ?

this tool was made in China JBrain and we can therefore assume it was not produced according to international quality standards. moreover, the question remains what kind of measuring units are shown on this tape.

if it shows Northern Manchurian Centipedes or Guangdong Millisquarewahliters you might have used an incorrect conversion when calculating the area of a room in your home located in Thailand.

please check again and report back. this is a serious matter which could be the reason that your aircon (who's brand can't be mentioned) does not work as expected.

p.s. it could also cause extensive damage to the inverter system of your compressor/condenser unit!

Ok, I admit that I cheated. This is how I measured the rooms

[Pattaya Pat]

Does this answer your question ?

this tool was made in China JBrain and we can therefore assume it was not produced according to international quality standards. moreover, the question remains what kind of measuring units are shown on this tape.

if it shows Northern Manchurian Centipedes or Guangdong Millisquarewahliters you might have used an incorrect conversion when calculating the area of a room in your home located in Thailand.

please check again and report back. this is a serious matter which could be the reason that your aircon (who's brand can't be mentioned) does not work as expected.

p.s. it could also cause extensive damage to the inverter system of your compressor/condenser unit!

Ok, I admit that I cheated. This is how I measured the rooms

That must have taken a while then

[infinity11]

bump

[jbrain]

So after 6 visits from the group of 5 technicians, and changing PCB over and over again they still couldn't get it to work.

About 10 days ago I got a call from the general manager in Bangkok, who expressed his concern and suggested a few more visits and test, and which made me really mad.

On my question why I couldn't get fixed in 6 weeks time, he told me that his technicians couldn't fix it at the moment, so I told him that he then better got of his lazy arse and fixed it himself or face the consequences of a OCPB involvement.

3 hours later he rang the door bell accompanied by 7 technicians.They worked till 9.30pm that night and couldn't get it fixed. The next Monday the technicians returned once again and performed further test without success, so I told them to inform their general manager that he had now 24 hours left to fix the issue.

Next morning at 10am the general manager together with the head technician is back again for a full day of working, changing refrigerant, changing PCB in the outdoor unit and more.

Still no positive result.

Right now they are here installing a complete new air-conditioning system free of charge .

[jbrain]

So after 6 visits from the group of 5 technicians, and changing PCB over and over again they still couldn't get it to work.

About 10 days ago I got a call from the general manager in Bangkok, who expressed his concern and suggested a few more visits and test, and which made me really mad.

On my question why I couldn't get fixed in 6 weeks time, he told me that his technicians couldn't fix it at the moment, so I told him that he then better got of his lazy arse and fixed it himself or face the consequences of a OCPB involvement.

3 hours later he rang the door bell accompanied by 7 technicians.They worked till 9.30pm that night and couldn't get it fixed. The next Monday the technicians returned once again and performed further test without success, so I told them to inform their general manager that he had now 24 hours left to fix the issue.

Next morning at 10am the general manager together with the head technician is back again for a full day of working, changing refrigerant, changing PCB in the outdoor unit and more.

Still no positive result.

Right now they are here installing a complete new air-conditioning system free of charge .

As i said in my previous post, technicians were installing a complete new system and left my place at 11.30pm.

All I can say for now is................................To be continued