A/C unit model efficiency?

[Disco Biscuit]

I'm looking for a way to determine the efficiency of my A/C unit (model Lennox # hs29-024-1p).

The biggest reason for this is that I intend to be in this house for a long time and my A/C usage is by far my biggest summer electricity expense. I'm in the process of buying solar panels and I don't want to cover too much of my energy usage in case it drops dramatically when I eventually have to replace my A/C unit (don't want to produce more power than I can use).

Anyone know anything about this, or can direct me to a reliable and user-friendly site/organization to determine this?

[bacchi]

http://www3.lennox.com/pdfs/brochures/Lennox_HS29_Air_Conditioner.pdf

Looks like 13 SEER. Not good but not horrible.

[kbishopnow]

Hold off for a couple years before upgrading: we are testing 21+ SEER units at the factory. They will probably be expensive, but they will be DC modulating and not have the big amp spikes during the constant start/stop cycles.

[Auricularia]

Heres a pretty neat tool to see if upgrading is worth it.

https://kobiecomplete.com/cool-tips/seer-savings-calculator/

[MMM98]

12 SEER is the federal min for AC units  That doesn't mean 13 is great or bad, it's just on the low end of 2016 standards.  Like so many things the gains in efficiency are reaped early and cheaply.  The improvement from 10 to 12 SEER was much more than 12 to 14 and it was meeting the 12 SEER standard was done by manufacturers with little cost.   Lobbyists to the Bush administration pushed for the 12 SEER standard vice the 13 that was in consideration.   There is your SEER history on MMM, the things you learn...

[FiftyIsTheNewTwenty]

Check with your electric company for rebates to help pay for a more efficient system (for example, $300 to upgrade to 15 SEER or better).

Also, make sure your system is sized correctly -- do a complete "Manual J" calculation.  Most systems are way oversized, so they cycle on and off excessively.  This is very inefficient, and doesn't give the dehumidification a chance to work.  So you wind up lowering your thermostat even more to compensate.

[Spork]

This advice was from 2009... so I am sure it has changed and is mostly out of date.

When we built our house, I spoke with an engineer that designed HVAC units for a large major brand.  His advice at the time was to buy 13 SEER units because that was where the break was on cost of unit vs efficiency.  In other words, in 2009 he felt the amount extra you spent on a 14 (or higher unit) was never going to be realized in savings.

[MrSal]

My opinion is if you want AC a mini split system such as Mitsubishi has is the way to go... cheaper... no need for ducts and as many materials and much more efficient (these units are 25-30 SEER).

Work like a charm. In europe its all they use pretty much and it works pretty well. In Portugal where I am from and temps in the South are like 100+ these units handle it easily. And cheaper to operate too since you can turn on only the air handler in the room you are in.

[FiftyIsTheNewTwenty]

^^^

I agree about mini-splits, but in the US the equipment costs a lot more and takes a long time to pay for itself, if ever, vs. just upgrading an existing ducted system.

If you're starting from scratch or your ducts need a lot of work anyway, mini-splits make a lot more sense.

Mini-splits are quieter and more comfortable than most people's ducted systems.

[MrSal]

^^^

I agree about mini-splits, but in the US the equipment costs a lot more and takes a long time to pay for itself, if ever, vs. just upgrading an existing ducted system.

If you're starting from scratch or your ducts need a lot of work anyway, mini-splits make a lot more sense.

Mini-splits are quieter and more comfortable than most people's ducted systems.

I agree they are more expensive than in Europe but while searching online i have seen very good prices such as 1500-2000 dollars for compressor + 3-4 air handlers and all materials for installation.

I hear a lot of peoople saying a new compressor and installation sometimes runs them 3-4k alone... when considering duct work 6-8k which is outrageous!!