Results 1 to 9 of 9
  1. #1
    Thailand Expat Jesus Jones's Avatar
    Join Date
    Aug 2008
    Last Online
    22-09-2017 @ 11:00 AM
    Posts
    6,953

    A/C and wiring gauge thickness?

    First of all, i know this is the wrong section.

    Mods, is there any reason i can't post in the Building section? That hasn't happened before! Could you move it for me please?
    -----


    I'm about to have some new a/c units fitted; after knocking the kitchen wall down the one we have isn't coping very well. The plan is to move this unit to a smaller room and replace the aging unit in the small bedroom.

    1. As for wiring, is 6mm required for a 24k (New replacement) BTU unit?

    2. The living room and kitchen are now open plan. Would it be better to use two smaller BTU units 12k each at both ends of the room (also cheaper). Or would one unit at 24k be better.

    Thank you
    You bullied, you laughed, you lied, you lost!

  2. #2
    Thailand Expat
    nevets's Avatar
    Join Date
    May 2008
    Last Online
    16-02-2015 @ 12:11 PM
    Location
    PHETCHABURI
    Posts
    1,630
    The in rush / starting current is about 60amps and will run at about 6amps i say about because the voltage if like mine will go up and down 190 to 220v, 4mm cable would do .
    Look at the speke on your units.

    You could use two 12btu they do in shops use 2 and 3 units in the same area.

    I have a 40k btu in the living room that pulls 80 amps on start up for about 3sec. and runs at 8amps.
    Last edited by nevets; 29-04-2012 at 10:01 AM.

  3. #3
    Thailand Expat Jesus Jones's Avatar
    Join Date
    Aug 2008
    Last Online
    22-09-2017 @ 11:00 AM
    Posts
    6,953
    ^Cheers for the input.

    At present we have an 18k BTU unit which in my opinion wasn't big enough to start with. I'm now considering running a new one along side it at the opposite end to compensate. As i mentioned the kitchen and LR are now open plan.

  4. #4
    Thailand Expat
    Airportwo's Avatar
    Join Date
    Mar 2006
    Last Online
    Yesterday @ 09:53 PM
    Location
    Flat Earth
    Posts
    3,499
    I would put 2 each 12k units, more efficient and certainly be cheaper to run in the long run....

  5. #5
    Member

    Join Date
    Dec 2009
    Last Online
    19-06-2015 @ 07:24 PM
    Location
    Isaan
    Posts
    335
    The standard Thai electric meter on the pole outside of your house is only 5 amps. You will need to have this upgraded to 15 amps to run multiple air cons at the same time. You will also need to install a circuit breaker for each air conditioner unit in the house.

    Wire size needs to be calculated for load draw or the amount of electricity at start up. Air cons typically draw around 65 amps but it can be more depending on the size of the air con.

    Copper wire is the preference for electrical motors

    Here are some simple formulas

    Amps = Watts / Voltage

    1 BTU = 0.2930711 Watt-Hour

    12 gage wiring can handle 20 amps

    10 gage wiring can handle 30 amps

    8 gage wiring can handle 50 amps

    (3) 6 gage wires in a conduit will safely handle 65 starting amps

    With wiring, it is best to have oversized and not marginal size.

    The current draw of two units may be higher than the current draw of one unit resulting in a higher electric bill. You need to research the continuous amp draw for the (2) units (add the amps together) versus the continuous amp draw of the larger unit to see which one uses the least amount of amps.

    The start up current draw is greater than the continous operating draw

    Wiring has to handle the start up load most importantly

    Another issue to consider is the size of the outside electric meter.

    You want to make sure if you are running multiple A/C's, hot water heaters, clothes dryer, microwaves or ovens at the same time that they are not using combined amps greater than your outside meter.

    The Air Con's need their own circuit breaker separate from the wall socket wiring.

    I have found most local air con shops that sell air cons will come move and rewire the air cons for you for less than 1,000 baht. In my area it was around 600 baht.

    I used National Circuit Breakers inside my house. Power and ground run straight from outside into the Circuit breaker, then to the air con. The breaker has a manual shut off switch in case of overload.

    One thing I have studied:

    When using an 18,000 BTU air cond downstairs all day maybe 12 hours, then a 14,000 BTU upstairs at night, shutting off the downstairs unit, the electric bill jumps 3800+ THB per month from not using any air conditioning.

  6. #6
    Thailand Expat
    dirtydog's Avatar
    Join Date
    Jun 2005
    Last Online
    @
    Location
    Pattaya Jomtien
    Posts
    58,776
    Quote Originally Posted by liveinlos
    The standard Thai electric meter on the pole outside of your house is only 5 amps.
    HUH? You spying on him?
    Quote Originally Posted by liveinlos
    12 gage wiring can handle 20 amps 10 gage wiring can handle 30 amps 8 gage wiring can handle 50 amps (3) 6 gage wires in a conduit will safely handle 65 starting amps
    This isn't Thai wire for Thailand I take it?

  7. #7
    Thailand Expat
    nevets's Avatar
    Join Date
    May 2008
    Last Online
    16-02-2015 @ 12:11 PM
    Location
    PHETCHABURI
    Posts
    1,630
    Even 15 amp is to low for the mtr but most soys around me have only 16mm cable along the soy .
    I wanted 35mm cable to the house because of the AC but was told why as the soy is 16mm .
    Well all my lights are low wt consumtion and 4 AC units but only 2 are used at a time mostly.
    Bigest problem we have is the volt drop at peek times 220vac can drop to 190vac , this can be bad for AC units but we have had luck so far no problems in 10 yrs in the house .
    Oh we have volt and amp meters on the main panel.

  8. #8
    Thailand Expat
    nevets's Avatar
    Join Date
    May 2008
    Last Online
    16-02-2015 @ 12:11 PM
    Location
    PHETCHABURI
    Posts
    1,630
    Quote Originally Posted by dirtydog View Post
    Quote Originally Posted by liveinlos
    The standard Thai electric meter on the pole outside of your house is only 5 amps.
    HUH? You spying on him?
    Quote Originally Posted by liveinlos
    12 gage wiring can handle 20 amps 10 gage wiring can handle 30 amps 8 gage wiring can handle 50 amps (3) 6 gage wires in a conduit will safely handle 65 starting amps
    This isn't Thai wire for Thailand I take it?
    Yes i think its American speak and will be based on 120vac.

  9. #9
    Banned
    Join Date
    May 2012
    Last Online
    18-05-2012 @ 10:19 PM
    Location
    Africa - turn left at Morroco
    Posts
    28
    Quote Originally Posted by liveinlos View Post
    The standard Thai electric meter on the pole outside of your house is only 5 amps. You will need to have this upgraded to 15 amps to run multiple air cons at the same time. You will also need to install a circuit breaker for each air conditioner unit in the house.

    Wire size needs to be calculated for load draw or the amount of electricity at start up. Air cons typically draw around 65 amps but it can be more depending on the size of the air con.

    Copper wire is the preference for electrical motors

    Here are some simple formulas

    Amps = Watts / Voltage

    1 BTU = 0.2930711 Watt-Hour

    12 gage wiring can handle 20 amps

    10 gage wiring can handle 30 amps

    8 gage wiring can handle 50 amps

    (3) 6 gage wires in a conduit will safely handle 65 starting amps

    With wiring, it is best to have oversized and not marginal size.

    The current draw of two units may be higher than the current draw of one unit resulting in a higher electric bill. You need to research the continuous amp draw for the (2) units (add the amps together) versus the continuous amp draw of the larger unit to see which one uses the least amount of amps.

    The start up current draw is greater than the continous operating draw

    Wiring has to handle the start up load most importantly

    Another issue to consider is the size of the outside electric meter.

    You want to make sure if you are running multiple A/C's, hot water heaters, clothes dryer, microwaves or ovens at the same time that they are not using combined amps greater than your outside meter.

    The Air Con's need their own circuit breaker separate from the wall socket wiring.

    I have found most local air con shops that sell air cons will come move and rewire the air cons for you for less than 1,000 baht. In my area it was around 600 baht.

    I used National Circuit Breakers inside my house. Power and ground run straight from outside into the Circuit breaker, then to the air con. The breaker has a manual shut off switch in case of overload.

    One thing I have studied:

    When using an 18,000 BTU air cond downstairs all day maybe 12 hours, then a 14,000 BTU upstairs at night, shutting off the downstairs unit, the electric bill jumps 3800+ THB per month from not using any air conditioning.
    The standard domestic electric meter in Thailand is not 5 amps - it is 15 Amperes/ 45 Amperes loaded. - plus some of the above calculations are incorrect - i.e. Amperes= Watts/Voltage, simply not true, this only applies in a pure DC circuit - AC - i.e. your home follows a different set of rules.

    5 Ampere metres are for the agricultural side of things and I believe are tax free. (I know, I was fined for using the 5 Ampere job to supply my house)

    The other option may be to look at 3 phase, putting your heavy current devices on one or two of the phases and the rest of your normal lighting etc. on the third phase.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •