Floor A/C: How much less efficient than window?

[Hal65]

I live in a 1 bedroom in a central area for only 5k a month, a real bargain. But the reason for the bargain is that the room was sold as a fan room. The window A/C unit (or is it a "wall a/c"? Typically thin AC placed above the window) is busted and yellowed apparently from being dead for years.

 

I want an A/C and am thinking what the best route to get there would be. A 1 bedroom around my area would be at least 12k (haven't even seen this price) or likely 15k a month. A floor AC that I buy would be less efficient and I'm paying 8 baht per unit. There is also the remote possibility of repairing the window A/C at my expense though I doubt this will work (landlord could have made his money back on it fast if it were a reasonable bill).

 

Can you guys give me an idea how many units I might use for the following, for a window ac vs floor ac:

 

1. 35 sqm

2. 20 hours per day usage, 30 days

 

Thanks for any estimates

[soistalker]

Twenty hours a day seems like a lot. May I ask why you you need the air con on all the time?

[rijb]

Buy a small wall unit.  Keep the old one.  When you leave, swap them back.  And sell the new one.

[RBOP]

Generally in Bangkok its sq.m x 700 = required BTU. So 35x700 = ~24K BTU which is big expensive unit (35K to 50K baht). Is your bathroom and kitchen separate rooms? If so then deduct those areas and recalculate. I've used wall mounted, floor mounted and cassette ceiling air cons. They all cool nicely. Mitsubishi is a top brand and you pay a little more but will last a long time. You should also consider how noisy the units are (both indoor and outdoor) for your comfort as well. Personally, I would not buy an aircon for the landlord. Let him/her buy it but expect your rent to go up too. Or just move.   

[themerg]

get window unit. Don't make it easy for the snakes.

I don't know how you would floor install, floor install is central air conditioning.

[r136dg]

When you say window unit I'm pretty sure you mean the typical split AC here & floor unit being the mobile unit that can moved room to room. 

The floor units are massively inefficient & at 8 baht per unit, 20 hours a day, you'll be taking out loans to pay that bill. They also have an exhaust on them that has to be ran outside & intake that will be pulling air into your room from outside. I have one in the garage I rarely use but next time I fire it up I'll record & post the amps & watts it's pulling.

I also have Daikin inverter split unit AC's in the house. I know a lot of people don't like inverters here but these things are very efficient. Very impressed with our 1st months electric bill (new home). They're priced up there with Mitsubishi. 

Also have a regular old Samsung split unit that's been through the last 2 houses we rented and's still going strong.

 

[RBOP]

also expect your electric bill to go up to 1,500 - 2,000 baht/month or more.

[HooHaa]

2 hours ago, soistalker said:

Twenty hours a day seems like a lot. May I ask why you you need the air con on all the time?

perhaps so the room remains cool?

 

[StevieAus]

2 hours ago, r136dg said:

When you say window unit I'm pretty sure you mean the typical split AC here & floor unit being the mobile unit that can moved room to room. 

The floor units are massively inefficient & at 8 baht per unit, 20 hours a day, you'll be taking out loans to pay that bill. They also have an exhaust on them that has to be ran outside & intake that will be pulling air into your room from outside. I have one in the garage I rarely use but next time I fire it up I'll record & post the amps & watts it's pulling.

I also have Daikin inverter split unit AC's in the house. I know a lot of people don't like inverters here but these things are very efficient. Very impressed with our 1st months electric bill (new home). They're priced up there with Mitsubishi. 

Also have a regular old Samsung split unit that's been through the last 2 houses we rented and's still going strong.

 

I don't want to open a debate about the merits or otherwise of aircon with inverters but have been using them for a couple of years and while more expensive initially are cheaper to run and seem more efficient

[AboutThaim]

2 hours ago, HooHaa said:

perhaps so the room remains cool?

 

What? Stay in your room 20 hours a day?

[bazza73]

I very much doubt a window aircon will have enough grunt to cool 35 sqm - also, they are quite noisy.

For a split system, the OP is looking at a 18,000 to 20,000 BTU aircon. Panasonic have crappy switch systems, go for a Toshiba or Samsung. Agree Mitsubishi is also a good brand.

Don't listen to the sales types who claim you need 40,000 BTU for 35 sqm. Their only skill is upselling.

[HooHaa]

14 minutes ago, AboutThaim said:

What? Stay in your room 20 hours a day?

who are you to question how other people live?

 

the guy lives in a 5k per month fan room, where the hell is he going to go?

 

[AboutThaim]

58 minutes ago, HooHaa said:

who are you to question how other people live?

 

the guy lives in a 5k per month fan room, where the hell is he going to go?

 

And who are you to question my question?  He can go anywhere there is free aircon or is he that broke that he can't afford to go anywhere? But still considering buying a new aircon for his rented room.

[tryasimight]

Beware of the floor units.  They feel great when you are in Big C or some already airconditioned building since they are pumping already cooled air around. Different story when you get them home and realise you need quite a large hose hanging out of a window somehow and have to work out a way of sealing it.

 

There used to be a window mounted unit called a Skinny Mini from memory.  As the name implies they were quite narrow and sat  in a sliding window frame. The window was then closed until it contacted the unit....job done. Don't know if they are still available.

 

[Hal65]

11 hours ago, soistalker said:

Twenty hours a day seems like a lot. May I ask why you you need the air con on all the time?

 

Maybe I won't need it that often, I moved here from California where we almost never used A/C. So my knowledge of how often these need to be run is limited. I'd expect temperatures on the outside and inside to normalize fairly fast though (walls are concrete I believe).

 

 

Regarding the usage estimate, I just wanted a high estimate. I do spend a lot of time at home though.

 

 

[Dazinoz]

19 hours ago, r136dg said:

They also have an exhaust on them that has to be ran outside & intake that will be pulling air into your room from outside.

Not correct. They exhaust the hot air to the outside via a tube but the intake air is circulated from within the room. No air comes back in through the exhaust tube. 

[Dazinoz]

10 hours ago, Hal65 said:

 

Maybe I won't need it that often, I moved here from California where we almost never used A/C. So my knowledge of how often these need to be run is limited. I'd expect temperatures on the outside and inside to normalize fairly fast though (walls are concrete I believe).

 

 

Regarding the usage estimate, I just wanted a high estimate. I do spend a lot of time at home though.

 

 

I did put a form on another thread for you to fill in and I can input into software written by a refrigeration engineer and give you a more accurate information on size of unit required. 

 

When people ask ask what size unit should I buy for this room is a bit like asking how long is a piece of string. AC sizing depends on many factors. If you buy a too small unit it will run continuously and maybe not cool room sufficiently. If too big it will cut in and out too often and become inefficient. An inverter model eliminates most of the latter problem. Inverter units are great when they are running correctly. If the electronics, which they have a LOT of become faulty they can be very expensive to repair. At least they were in Australia. They are prone to vermin and geckos and power fluctuations. 

 

Try this link   Page 4

 

 

[r136dg]

7 hours ago, Dazinoz said:

Not correct. They exhaust the hot air to the outside via a tube but the intake air is circulated from within the room. No air comes back in through the exhaust tube. 

Not sure where you got "air comes back in through the exhaust tube" from my post, but just to clarify;-)

Yes, hot air from the condenser is ran outside & intake is air from within the room, however; with all that exhaust going out you're depressurizing the room. All that exhaust air has to be replaced & it is, through every gap in the windows & doors, hence; pulling air into your room from outside.

That has to cover at least 50% of the inefficiency from those units.

[Dazinoz]

15 hours ago, r136dg said:

Not sure where you got "air comes back in through the exhaust tube" from my post, but just to clarify;-)

Yes, hot air from the condenser is ran outside & intake is air from within the room, however; with all that exhaust going out you're depressurizing the room. All that exhaust air has to be replaced & it is, through every gap in the windows & doors, hence; pulling air into your room from outside.

That has to cover at least 50% of the inefficiency from those units.

Yes you are correct. Not really thought about that.