Tell us about your furnace.

Age, brand, size ,complete model number(very important).

Generally you will need an outside AC condenser, pad, correctly sized refrigerant lineset, and matching evap coil. Eff of AC condenser will depend on the furnace you currently have. If not a var speed model, you should stick with a good quality 13 SEER model. I will not recommend any builder grade low end, foreign made POJ.

Post back.

IMO

I do not know the age, but it is before 2009. The unit says Lennox Elite Series PMAC-12C. I do not believe that it is a variable speed model because we do not use much heat and only turn the heat on from December through March and sometimes April. Typically, it does not get below 45 degrees in the winter, but in can get down to 37 degrees in extreme years. The average high in December-January is in the upper 60s, and so I do not use heating during the day. At this point, I think summer heat is more of a problem than winter cold, as far as climate goes.

Do you need more info about my heater? There were a lot of instructions on it, but not much technical information.

Thanks for your help!

Lars

Yes, need more info on the furnace in particular efficiency, BTUs, and rated blower size.

IMO

Here is a photo of the heating unit in my attic. I rotated the photo, but the part on top is actually on its side and is 40" x 28" x 14-1/2". The smaller part is 10" x 28-1/2" x 18"H. There is no mention of BTU on any of the text that I can find, but there is a reference to a Honeywell VR8200, which I believe is a switch.

I can blow up the text, if there is anything that you think may be helpful. Mostly it is just instructions and warnings without any specifics regarding this unit. I think that information is in the instruction booklet, and the previous owner did not keep any instruction booklets and told us we would have to get all our information on line. That has not worked all that well for us, and I am still not completely sure how to use our thermostat.

Lars

You have given me the model number of the air cleaner, not the furnace. Without the model number of the furnace, I will not be able to help you.

IMO

I found the number LB-86894A on the white label on the furnace. Is this the model number? If not, it might be on the bottom of the furnace where I cannot access it.

The size of the furnace is 40" x 28-1/2" x 14-1/2", approximately, not including the air cleaning part.

Lars

I opened up the furnace to find the model number:

LENNOX FURNACE
M/N: G50UH-36A-070X-06
S/N: 5803K 07637

Here is a link to the manual. It appears to be 66,000 Btuh input and 54,100 Output Btuh. Hope this helps!

Lars

This post was edited by publickman on Tue, Sep 2, 14 at 18:14

'rated blower size' is not in inches. It has to do with the BTU 'size' of the furnace. The bigger (more) the BTUs , the bigger the blower. The point being we would need to know the 'size' of the blower in order to pick a range of sizes for the AC (without having to replace the furnace)

With the crazy electrical rates in LA you might want to think about a better SEER than 13, like 14/15/16. Ask for the costs and we could work out the estimated payback time on the investment.

The other thing I will say is the dealer will tell you what he sells and services. He will quote you based on what he sells.

And American Standard is the 'cheaper' side of Trane. Not lower quality, just a lower price.

A dealer will need to do a measurement of you house called a 'Manual J' assessment. If you are good with computers and numbers, there are free software programs out there that can do a decent job of this for you. You need the size of your rooms, number/type of windows, insulation values for walls and ceilings, desired temps and outdoor temps, and some other stuff. Software chews on this and tells you what size cooling and heating system you should have.

In your case I would check with a Lennox dealer. They make some very good AC units and may be more compatible with you furnace. The more common components in your heating and air the better in my opinion.

OK, it appears you have finally located the true furnace model number and you have a 3 ton rated blower.

Now you need to get sized correctly. I would think probably a 2 1/2 ton AC condenser. I would want a good 13 SEER model. You can go with any brand. I will not recommend a low end POJ model. If that's what you are after, you are on your own. If not I can give you several possibilities.

IMO

I am not interested in low end, but I do not want to buy more than I need.

Are there better brands of 13 SEER models? It seems that the reviews I read of HVAC from end users is that they hate all of them - A/C and furnace alike. That makes it difficult to find one that is recommended. I'm okay with Trane if that brand is better.

Lars

American Standard Allegiance 13 Model

Trane XR13 Model

Bryant Preferred 13 Model.

Lennox XC13 Model

All will require matching evap coil.

I prefer Lennox the least of the four I listed.

Do not accept any third party evap coil.

IMO

This post was edited by tigerdunes on Tue, Sep 2, 14 at 17:08

Thanks, IMO. Did you list the brands in order of preference? I went to the American Standard web site and found a dealer/installer who is going to meet me tomorrow for a quote. I'll post what they say and what they recommend.

There is a Trane dealer in Santa Monica, but everything seems to be more expensive coming from SM, although it is closer than the other dealers. There is a Bryant dealer in Torrance, and I will call them after I meet with the American Standard dealer. I tried to call the installer in Westchester, but his voice mailbox is full, and so I was unable to leave a message.

I will make a note to watch out for third party evap coil.

Thanks again, and I will let you know how it turns out.

Lars

Check how much room there is above the furnace to install the cooling coil - they can be up to 24" tall.

I'm not a big fan of Lennox. Not because they are poor quality but rather because they tend to be a little expensive for what they are.

Given your climate in W LA, get a cooling load calculation done - it can be a little humid there by the ocean (unlike, say, the Valley). 3 tons may be a little high for 1500 sq ft by the ocean and won't dehumidify as well as 2 or 2.5 tons.

I thought the A/C unit would have to be outside - I did not expect it to be on top of the furnace.

I will not be buying Lennox - I did not choose the heating unit, but it has worked fine for us, but then it doesn't get that cold here.

This is the dealer who will be meeting with me tomorrow. His license number is listed as unavailable, and so I guess I should ask for that first. Any other credentials I need to see? The web page says that they have 99% satisfaction, but I do not know where that comes from.

Here are the Yelp Reviews for the installer in my neighborhood (Westchester), but I was unable to leave him a voice message today, as his voice mailbox is full. I think I should still try with him, however, as others say that his pricing is better than the competitors.

Are two quotes enough? I will tell them that I am flexible with brands, preferring American Standard, Trane, or Bryant. I am considering contacting One Way Air in Torrance, but I cannot find any reviews of this company or get much info about them. Should I bother asking them for a quote?

I definitely plan to go with a 2.5 ton unit. It's not that humid here - generally in the 50% range, and so it's not that dry either, but not humid enough to need to dehumidify.

We bought the house in Westchester while we were living in a house in Venice, less than a mile from the beach, and it was definitely more humid there. Also, it NEVER got below 45 degrees in the winter, but it never got warm either, and we only had a wall unit in the middle of the house for heating. We bought a window unit for A/C, which we brought with us to Westchester, but the house here is almost twice as large as the one in Venice, and we moved here partly because real estate is way too expensive in Venice - twice what it is here per square foot. We opted for space vs proximity to the beach, but are still in the same general area.

Lars

In the meantime, you can get much more relief from a simple window unit if you place a narrow window fan in a central location (a bathroom window is ideal) venting outward, set on LOW. That will pull the cool air you do have through the portion of your home between the ac and the window fan location,

My DB developed this method in a two story house with an upstairs ac unit and a vent fan in the downstairs back hall, and it kept the entire house bearable for years. The method works even better in a ranch house configuration, and also helps control humidity.

Not much cool air is lost--what really happens is it pulls the cool air away from the ac unit so it is easier for it to pump more cold air into the room it is in. Additionally, the room the ac is in does not get as overly cool as it otherwise would.

[We considered getting central air, but actually like this method better, as we do not have to hermetically seal off our house from fresh outdoor air. However, it also works because we have several large trees surrounding our home, and excellent attic insulation, as well as an enclosed carport with a concrete slab floor which can retain coolness for long periods of time.]

Stay cool!

I use that method in the kitchen - I have a fan near the kitchen window, and during the day, I have the fan blow air out, but at night, I have it bring cool night air in, as it does not stay hot here at night. We have ceiling fans in all the bedrooms (one bedroom is supposed to be an exercise room, but it has been too hot for that lately), and we have a floor fan in the living room. We're tired of this arrangement by now, although in Venice it worked fairly well, as the summer temps rarely got above 80 degrees there, although when they did, I was very uncomfortable.

For most of the year, we keep windows open, but during the hot and cold months, I would prefer conditioned air. We only have 3-4 months when we heat, and even during the winter we have warm days when I open the windows. Summer is definitely the worst time, and September is our hottest month. October can also be very warm, but it is nowhere nearly as bad as it was in Texas. My sister does not think we need air conditioning, but she keeps her thermostat at 80.

Lars

The outside condenser goes outside. The matching evap coil will connect to the furnace.dealer will need to take measurements to see how much room you have.

IMO

Thanks! I do think there is room, but I haven't measured it yet. I will make sure that they look at that area.

Lars

This unit is actually lying on it's side, right?

IMO = In My Opinion. Not his name.

The unit is lying on its left side facing, and so if you rotate the photo I posted 90 degrees counterclockwise, it will be in its actual position.

I met with the first installer today, and he gave me a good price ($4600) for American Standard unit 3 ton, 13 SEER, and that included all installation requirements. What threw me off a bit was that he said if I wanted to install the outside unit where I wanted it in the first place, he would do it there, but it would be against code and he could not pull a permit for it. I told him that I was not interested in doing anything against code or without permits, but I guess some people do. We found another place to put the outside unit that would go through my garage and not ugly up my back yard.

The guy from Westchester will be here tomorrow after work to give me another estimate, and then someone from Bryant will give me an estimate next week. I wasn't planning on having more than two estimates, but I guess it is better to have three, although I may cancel the Bryant estimate if I decide to go with the Westchester guy.

It appears that there is room for the condenser in my attic, but some of the ducting will have to be moved somewhat. Also, the heater needs to be reattached because it is being supported by straps at the moment, and the guy today said that he would replace those with brackets.

Lars

Let's be sure of your terminology. AC condensers are to be placed outside definitely not inside in an enclosed area or attic. Evap coil connects to furnace. Refrigerant lineset connects between the condenser and evap coil.

I think 3 ton is too large. Document that size.

IMO

I meant to say that there is room for the coil in the attic, and the condenser will go outside next to my garage.

I am getting another quote this evening, and I will see if he recommends the 2-1/2 ton. The first guy said that his calculation was based on one ton per 500 square feet and that it matched what my heater has. He was trying to tell me that a 3 ton would be more economical than a 2-1/2 ton unit.

The furnace is a fair distance from the garage (about 20 feet or so) - does this present a problem? By the way, I have nine ducts in my house. I am also going to want a new thermostat, as the one I have is probably 10 years old or more, and I have trouble operating it.

Lars

We selected a bid and will be getting a Bryant Slimline model #538ANR036000, to be installed in a fairly narrow space beside the house. It is very far from the neighbor's house, however, as there is a garage between us. This is a 3-ton, 13 SEER model, and it looks like we will have to upgrade to 230 volts from our circuit box. At some point, I will want to upgrade the entire box so that we can install outdoor lighting, but that can wait, as I already have lighting in the pergola and on the north side of the house. The back yard is mostly unlit, except for small lights inside the fountain.

We were considering American Standard 4TTB30361000A, but it is too large (and perhaps too noisy) for the location that we want. The location we will be using is next to the outdoor water heater and in front of the storage unit for the lawn mower. It is the most hidden part of the back yard and close to the exterior kitchen door.

Thanks so much for your help in this decision process!

Lars

Don't believe 3 ton is the correct size. How was this determined?

What Mdl evap coil?

IMO

This post was edited by tigerdunes on Tue, Sep 9, 14 at 16:13