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View Full Version : Interpretting ARI data for unitary Heat pumps


cpetku
10-03-2008, 08:13 PM
So if I look at two similar sized systems (ARI 1416467 vs 1409806) I see that the Bryant 2 stage scoll HP appears inferior to the York 2 Stage scroll HP with both being rated 4 tons and using a 5 ton coil on a 4 ton AH.

1) Is it appropriate to shop for equipment by searching the ARI database for a well performing system? If not, why not?

2) Anyone have recent experience with the York Affinity series? Other than Byrant having an "eye candy" thermostat, is there really any advantage for this brand?

3) 2 of the 3 contractors which have quoted a system do not believe in doing a Manual J calc. The one that did, seemed to be too busy installing Geo's to provide an actual quote on the equipment he recommended (a similar package from Amana). Is manual J really necessary if I can estimate heat loss from old bills?
rponson
10-05-2008, 12:19 AM
So if I look at two similar sized systems (ARI 1416467 vs 1409806) I see that the Bryant 2 stage scoll HP appears inferior to the York 2 Stage scroll HP with both being rated 4 tons and using a 5 ton coil on a 4 ton AH.

1) Is it appropriate to shop for equipment by searching the ARI database for a well performing system? If not, why not?

this is a good tool but as you have found out it does not tell the whole story. It is mearly a comparison of unit to unit at a given condition

2) Anyone have recent experience with the York Affinity series? Other than Byrant having an "eye candy" thermostat, is there really any advantage for this brand?

I am not familiar with the York but the Evolution stat is more than "EYE Candy". It is intuative. It will look at how you use the house and change run parameters for the best comfort

3) 2 of the 3 contractors which have quoted a system do not believe in doing a Manual J calc. The one that did, seemed to be too busy installing Geo's to provide an actual quote on the equipment he recommended (a similar package from Amana). Is manual J really necessary if I can estimate heat loss from old bills?

Without a proper load calculation they are GUESSING with YOUR MONEY.