single stage vs 2-stage

[ebit123]

Ok, I need to know if this is true or someone trying to rip me off. This one company's salesperson said if I get a single stage furnace and a 14-seer ac, the ac won't get up to 14 seer. So, he;s saying I need to get a 2-stage furnace in order to get the full energy savings from the 14 seer. No one else has said this to me. What do you guys think? is this true?

[summit]

The stages of heat have nothing to do with a/c SEER. A variable speed blower will usually increase the a/c ARI efficiency rating. Ask if the furnace has a variable speed blower. Better yet ask for the ARI certificate of performance showing the efficiency rating of your quoted equipment. Make sure the model numbers match. Or ask for the model numbers and look it up yourself at: http://www.aridirectory.org

[seatonheating]

Originally posted by summit
The stages of heat have nothing to do with a/c SEER. A variable speed blower will usually increase the a/c ARI efficiency rating. Ask if the furnace has a variable speed blower. Better yet ask for the ARI certificate of performance showing the efficiency rating of your quoted equipment. Make sure the model numbers match. Or ask for the model numbers and look it up yourself at: http://www.aridirectory.org

I'm not sure I've even seen a single stage variable...do they even exist?

Nonetheless, he is not trying to rip you off. To try and coax 14 SEER out of an AC without upgrading to a new/2 stage furnace doesn't make sense. Sounds like the contractor is right on, maybe he just needs to work on his explanations.

[arc8]

Now you know, do not let that company install anything, seeing they know nothing, period.

Have a good day.

[ebit123]

the single stage furnace is a trane xt series. It says on trane's website that the blower has four speeds. does that mean it's variable?
thanks for your help.

[mayguy]

Originally posted by ebit123
the single stage furnace is a trane xt series. It says on trane's website that the blower has four speeds. does that mean it's variable?
thanks for your help.

No, it's not. the XV90/80 is variable speed.

The 4 speed is a multi speed. To be honest, if you plan on being in the home long term, you be very glad you upgraded to a variable speed/2 stage heating system. Variable speed blower runs very quiet in cooling mode, and if you like fan "ON" to mix the house air or has an air cleaner, it is the way to go.

Check with your electric company and see if they offer rebates on variable speed blower, Mine did.

[beenthere]

Some units require a VS blower to get their full SEER rating, so you may need the 2 stage VS furnace.

[furnace doctor]

The two stage air conditioner is a very good choice, equipment can size itself to the buildings load, just match with the right coil, furnace, even system control. Fancy control systems can control the speed of the blower from 400 cfm to 350 cfm when there is a high humidity condition.

Do check for the correct ARI information to get the SEER you are looking for.
http://www.ceehvacdirectory.org/ac.php?reset=true

[furnace doctor]

Look at the CEE site to locate the ARI info. It will show what furnaces Multi or Variable work with the Air conditioner model you are looking at.

[Edited by furnace doctor on 06-10-2006 at 12:41 PM]