Looking for input before I buy A/C unit

wilywes

Member
Feb 4, 2008
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I have a 236 square foot room with 9.5 foot ceiling, 4 foot windows on two of the walls protected with blackout curtains, room gets sun for the morning. I currently have a 12,000 BTU A/C unit, not an inverter type. I believe this one is 10 SEER. Anyway, I am considering buying a new inverter unit so I can have some power savings. An installer "professional installer" from Refripartes Puerto Plata recommended a 18,000 BTU unit, Lennox name brand. He says it has a 18 SEER rating but I have yet to confirm that for myself, which I will do before buying.  Price of unit is 34,000rd deinstall old unit 800RD install new unit 4000RD




Here are my questions, concerns if anyone with some experience can help...




Does 18,000BTU seem to large? All American BTU calculators show that a 12,000 unit should be more than fine.(20 BTU per square foot)




Second: Anyone here have experience with Lennox mini split A/C units here in the DR? 




Third: Any other suggestions, or comments on the stated prices (positive or negative).
 

cavok

Silver
Jun 16, 2014
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I have a 236 square foot room with 9.5 foot ceiling, 4 foot windows on two of the walls protected with blackout curtains, room gets sun for the morning. I currently have a 12,000 BTU A/C unit, not an inverter type. I believe this one is 10 SEER. Anyway, I am considering buying a new inverter unit so I can have some power savings. An installer "professional installer" from Refripartes Puerto Plata recommended a 18,000 BTU unit, Lennox name brand. He says it has a 18 SEER rating but I have yet to confirm that for myself, which I will do before buying.  Price of unit is 34,000rd deinstall old unit 800RD install new unit 4000RD




Here are my questions, concerns if anyone with some experience can help...




Does 18,000BTU seem to large? All American BTU calculators show that a 12,000 unit should be more than fine.(20 BTU per square foot)




Second: Anyone here have experience with Lennox mini split A/C units here in the DR? 




Third: Any other suggestions, or comments on the stated prices (positive or negative).

For a room that size, 12,000 BTU is more than adequate. I have a 12,000 BTU unit in my 200 sq. ft. bedroom and it will easily get down to 65F in a short time and I have 8 ft wide triple sliding glass windows on the back wall that leak air like a sieve.

Lennox is a good brand, but no experience with their split units.
 

windeguy

Platinum
Jul 10, 2004
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I am in about the same situation for a room that is a bit larger at 352 sq feet, slightly lower ceiling and three 4 foot windows.

When I previously shopped AC units for another bedroom, I found they just don't sell small capacity inverter units here. I think it is for that reason that they up sell you to a larger capacity unit than you need. Refripartes in POP sold us a Samsung 9,000 BTU unit that has worked for over a year now in our 200 sq ft bedroom.

Lennox should be a good brand. People that have talked about AC units before recommend Mitsubishi models, but I don't see them for sale on the north coast.

The most common brand is TGM. I live near enough to the ocean and replacement parts are a concern for my Samsung 9,000 BTU unit. For the new room I am just starting the search. I understand there is a TGM unit in a plastic casing, which may last longer in my area. And TGM parts are readily available.

I was just in POP and saw a couple of different businesses that used Lennox split units, so if you go that way, hopefully their being more common means parts are available to repair them.
 

wilywes

Member
Feb 4, 2008
84
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I am in about the same situation for a room that is a bit larger at 352 sq feet, slightly lower ceiling and three 4 foot windows.

When I previously shopped AC units for another bedroom, I found they just don't sell small capacity inverter units here. I think it is for that reason that they up sell you to a larger capacity unit than you need. Refripartes in POP sold us a Samsung 9,000 BTU unit that has worked for over a year now in our 200 sq ft bedroom.

Lennox should be a good brand. People that have talked about AC units before recommend Mitsubishi models, but I don't see them for sale on the north coast.

The most common brand is TGM. I live near enough to the ocean and replacement parts are a concern for my Samsung 9,000 BTU unit. For the new room I am just starting the search. I understand there is a TGM unit in a plastic casing, which may last longer in my area. And TGM parts are readily available.

I was just in POP and saw a couple of different businesses that used Lennox split units, so if you go that way, hopefully their being more common means parts are available to repair them.

I currently have an Excell unit (made by same company as TGM) with the plastic case. I have used it for 3-4 years, near the ocean and it is in great shape still. The installer actually commented on how good it looked while he was here just the other day. Def like the plastic casing.    
 

windeguy

Platinum
Jul 10, 2004
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I currently have an Excell unit (made by same company as TGM) with the plastic case. I have used it for 3-4 years, near the ocean and it is in great shape still. The installer actually commented on how good it looked while he was here just the other day. Def like the plastic casing.    

That is good to know that there are other names for the same unit (just like the small motos sold here all made by the same company, yet with 10 different brand names)

Where did you purchase the Excell unit and what is its SEER rating?
 

cavok

Silver
Jun 16, 2014
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I currently have an Excell unit (made by same company as TGM) with the plastic case. I have used it for 3-4 years, near the ocean and it is in great shape still. The installer actually commented on how good it looked while he was here just the other day. Def like the plastic casing.    

The TGM with the plastic case also has a special copper alloy condenser coil that does not oxiidize as rapidly as the aluminum coils on the standard unit. That's why it costs more, too. You're not just paying for a plastic case. I'd be willing to bet the Excell unit has the alloy condenser coil, too.

If you can get an inverter unit with the alloy coils and plastic case, it might be worth the extra money(?). Otherwise, the condenser unit will rot out before you can recoup the extra money saved on electric with the inverter.
 

wilywes

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Feb 4, 2008
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The Excell unit I got from Refripartes in La Romana back when I lived there about 5 years ago. It is only a SEER 10, not inverter type. Thats why Im considering changing it and putting it into the spare bedroom where it will get less use. TGM is from Florida and they have 3 in house name brands. Here is a link to their American website. In the about us section it talks about their brands a little.  http://www.refricenter.net/about-us.asp
 

wilywes

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Feb 4, 2008
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The TGM with the plastic case also has a special copper alloy condenser coil that does not oxiidize as rapidly as the aluminum coils on the standard unit. That's why it costs more, too. You're not just paying for a plastic case. I'd be willing to bet the Excell unit has the alloy condenser coil, too.

If you can get an inverter unit with the alloy coils and plastic case, it might be worth the extra money(?). Otherwise, the condenser unit will rot out before you can recoup the extra money saved on electric with the inverter.
Savvy point.
 

Mauricio

Gold
Nov 18, 2002
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You should buy an Inverter air conditioner bigger than you would a conventional A/C. Besides, US room size calculations aren't necessarily valid for DR climate. 18k btu seems fine to me.
 

wilywes

Member
Feb 4, 2008
84
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You should buy an Inverter air conditioner bigger than you would a conventional A/C. Besides, US room size calculations aren't necessarily valid for DR climate. 18k btu seems fine to me.
Thanks for the input Mauricio. May I ask why there is the need to buy a larger Inverter type A/C unit than the conventional?  The size calculations I used were based on the climate in Florida, which is a similar climate to the DR in my opinion, but maybe I'm wrong????

Refricentre (Refripartes American branch from Florida) recommends a 9000BTU unit based on my size. Funny though, cause refripartes in DR says 18,000BTU. Hence why I am asking on this forum .
 

cavok

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Jun 16, 2014
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You should buy an Inverter air conditioner bigger than you would a conventional A/C. Besides, US room size calculations aren't necessarily valid for DR climate. 18k btu seems fine to me.

There are numerous a/c sizing charts online. 18K BTU for a 236 sq. ft. room is serious overkill.
 

windeguy

Platinum
Jul 10, 2004
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Thanks for the input Mauricio. May I ask why there is the need to buy a larger Inverter type A/C unit than the conventional?  The size calculations I used were based on the climate in Florida, which is a similar climate to the DR in my opinion, but maybe I'm wrong????

Refricentre (Refripartes American branch from Florida) recommends a 9000BTU unit based on my size. Funny though, cause refripartes in DR says 18,000BTU. Hence why I am asking on this forum .

Florida is in general worse than the DR for cooling requirements. Don't go too over sized, in my opinion.
 

windeguy

Platinum
Jul 10, 2004
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The Excell unit I got from Refripartes in La Romana back when I lived there about 5 years ago. It is only a SEER 10, not inverter type. Thats why Im considering changing it and putting it into the spare bedroom where it will get less use. TGM is from Florida and they have 3 in house name brands. Here is a link to their American website. In the about us section it talks about their brands a little.  http://www.refricenter.net/about-us.asp

I suspect the TGM units are not made in Florida, but rather in China. The good news is that TGM has their "hub" for service in Florida, which is a good thing when parts are needed. I will investigate his further next week to discover where the manufacturing is done and who has what of their products in the DR.
 

cavok

Silver
Jun 16, 2014
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Thanks for the input Mauricio. May I ask why there is the need to buy a larger Inverter type A/C unit than the conventional?  The size calculations I used were based on the climate in Florida, which is a similar climate to the DR in my opinion, but maybe I'm wrong????

Refricentre (Refripartes American branch from Florida) recommends a 9000BTU unit based on my size. Funny though, cause refripartes in DR says 18,000BTU. Hence why I am asking on this forum .

9000 BTU for your room would be aqdequate. I bought the 12K BTU because the smaller sizes are hard to find and, if I leave my bedroom door open, the 12K does a fairly good job of cooling my living room area, too. My condo is not that big.
 

wilywes

Member
Feb 4, 2008
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I suspect the TGM units are not made in Florida, but rather in China. The good news is that TGM has their "hub" for service in Florida, which is a good thing when parts are needed. I will investigate his further next week to discover where the manufacturing is done and who has what of their products in the DR.
Yes you are right. My neighbor has a TGM and it says "Made in China" right on the side but like you said their hub is in Florida. My comments were a little misleading. 
 

wilywes

Member
Feb 4, 2008
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5
8
9000 BTU for your room would be aqdequate. I bought the 12K BTU because the smaller sizes are hard to find and, if I leave my bedroom door open, the 12K does a fairly good job of cooling my living room area, too. My condo is not that big.


 I definitely would not go with a 9k for the reasons you stated and that I like to have a little extra power for some fast cooling. But all things so far are pointing towards the 12k and not the 18k.  Any thoughts about the name brand? TGM vs Lennox? I have not seen any Mitsubishi in POP. There is Samsung at La Sirena. 
 

cavok

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Jun 16, 2014
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 I definitely would not go with a 9k for the reasons you stated and that I like to have a little extra power for some fast cooling. But all things so far are pointing towards the 12k and not the 18k.  Any thoughts about the name brand? TGM vs Lennox? I have not seen any Mitsubishi in POP. There is Samsung at La Sirena. 

It really doesn't hurt to be a little oversized. I would recommend the 12K BTU, plus parts will probably be easier to find. As far as brand name, you tend to get what you pay for, but if your unit is in a salt air environment close to the ocean where the condenser unit is the most likely thing to go, brand names might not be worth the extra money(?).

Owners here at the condo where I live have had good luck with TGM, AUX, Excel, and AirMax. I've always used TGM up until now. The last one I bought the condenser oxidized in only a year and a half(I live on the ocean). When new, the aluminum condenser coil fins were so thin they would bend just running your finger across them. The a/c tech guy said he's had a lot of complaints about that and the quality seems to have gone down. I bought the AirMax this time. Very nice unit. Much thicker condenser coil fins than my old TGM had.
 
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windeguy

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Jul 10, 2004
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I just called my best friends brother. He installs AC units for a living. He has worked for GE and now works for HEIR. He had heard of TGM, but has no experience with that brand.

He gave this rule of them calculation scheme for BTUs for a room with an 8 foot ceiling:

Take the square footage and divide by 500 then multiply by 12,000, add 380 per person and 1,500 per 6 foot wide window. Add about 1,000 per foot if the ceiling is over 8 feet high.

236/500 X 12,000 = 5,664 to start. Then add the considerations for number of people, windows and additional ceiling height. Since we normally have just cement block construction without insulation, there may be a factor of another 25% thrown in. For my new 16 X 22 music studio room, I am looking at a 24,000 BTU unit. Yikes...Three windows and a 10 foot ceiling.
 

wilywes

Member
Feb 4, 2008
84
5
8
I just called my best friends brother. He installs AC units for a living. He has worked for GE and now works for HEIR. He had heard of TGM, but has no experience with that brand.

He gave this rule of them calculation scheme for BTUs for a room with an 8 foot ceiling:

Take the square footage and divide by 500 then multiply by 12,000, add 380 per person and 1,500 per 6 foot wide window. Add about 1,000 per foot if the ceiling is over 8 feet high.

236/500 X 12,000 = 5,664 to start. Then add the considerations for number of people, windows and additional ceiling height. Since we normally have just cement block construction without insulation, there may be a factor of another 25% thrown in. For my new 16 X 22 music studio room, I am looking at a 24,000 BTU unit. Yikes...Three windows and a 10 foot ceiling.
this is great, thank you 
 

Cdn_Gringo

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Apr 29, 2014
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I bought new TGM Inverter 22 SEER ACs even though the old non inverter models still worked fine.

12,000 BTU is enough for your room size. If you can close off the room, you'll notice a temp drop within minutes. Get the highest SEER rating you can afford. An over sized unit will cool the air a bit faster but offset some savings with increased runtime energy use over a smaller unit. In such a small space the slight decrease in cooling time should not end up being a significant factor justifying the extra electricity usage.

Here with the cost of electricity I would not purchase a non-inverter AC less then 20 SEER. Harder to find the higher SEER models sometimes so sales people try to steer you towards a product that do have. When I was looking, 22 was the cost vs savings sweet point. I have already saved the extra cost in electricity savings.

Installation costs should be exactly the same and not dependent on what unit you purchase. There should be no cost to remove the old unit as they will be reusing the same holes and electrical connection for the new one I assume.

I would ask that the line set included with the new unit not be used and the installer use a new copper line set instead.