Air Conditioning in a 65 year old house (Santa Clara, San Rafael: living, bills)

[dave bacon]

Hi All,

We’ve decided to put AC in my Mom’s 65 year old house in SanRafael. She has central heat with a "thin boy" furnace, and we're thinking about central air, but we don't know much about AC. Looking for areputable company, and any suggestions/ideas on the best way to keep her cool.

Thanks in advance for your help!

[Ruth4Truth]

Probably her furnace is old and inefficient compared to new models. Often what happens in these cases is that a good company can give you a more compact and efficient furnace with an AC combination unit that fits into the space occupied by the current furnace unit. Invite several companies to come out and give you a bid, ask questions, see which proposal makes the most sense.

[BayAreaHillbilly]

San Rafael is right at the edge of where AC may or may not really make sense. Have you considered alternatives such as a whole-house-fan / attic-fan?

[clongirl]

Originally Posted by BayAreaHillbilly

San Rafael is right at the edge of where AC may or may not really make sense. Have you considered alternatives such as a whole-house-fan / attic-fan?

We have both of those and they do wonders (and I'm in a hotter area)!! I can't see spending 10k or more on an air conditioning system to be used for a few days out of the year in a place like San Rafael.

[NoMoreSnowForMe]

Easiest and cheapest thing to do is put in a window unit.

I've got one in my bedroom window in my 1 bdrm apt in Santa Clara. I use a big industrial type fan to blow the cool air into my living room. Even as hot as it gets here, my bedroom is always nice and cool (easily down to 70 degrees even when it's over 100 outside), and I can keep the living room (on the sunny side of the bldg) down to 80 degrees, even when it's over 100 degrees outside with the sun blazing on my west side apt living room.

If she'd rather have her living room cool, do the opposite with the fan.

You can have a happy mom for less than $200 :-)

[CarlosAtun]

Her 65 year old house probably has little or no underroof and wall insulation and leaky single pane windows, among other design features that don't contribute to energy savings. Maybe the best place to start would be to investigate adding insulation and replacing the windows. It is hard to air condition an older house without adding energy-saving features because the cold air just leaks out. Is it possible to install a ceiling fan in her bedroom? Because it cools down at night in San Rafael, and is not really all that hot all summer, perhaps a ceiling fan would be a place to start, or shade cloth exterior roller shades on west facing windows.

[eureka1]

Her utility bills will skyrocket. My friend in LA just put in a window unit and it has solved their problem.

[Ruth4Truth]

Window units are actually a lot more expensive than central air to run. Central air is more expensive to install, but very cheap to run.

[dave bacon]

Thanks much to everyone for your input. Mom doesn't want a window unit and she thinks the ceilings are too low for fans, so we're going to get some central air quotes. Any recommendations? Thanks again!

[shooting4life]

I would say just make sure the attic is properly insulated. The vast majority of ac/heat loss is via the attic. I believe I read something along the lines of 75% of loss is through the ceiling and into the attic.