Ashrae 90.1, section 6.4 minimun equipment efficiencies

Technically equipment efficiency is a mandatory provision and the project must comply with both COP and IPLV. The efficiencies are determined at ARI test conditions. Check with the equipment manufacturer to make sure you are looking at the ARI efficiency values for your equipment.

When you say "The efficiencies are determined at ARI test conditions" does that mean the particular equipment has to be listed in the ARI certified database? Or is it adequate if the equipment is tested by the manufacturer under ARI conditions even though it is not listed under ARI database of certified products?

Augustine, I believe that this is a common problem in non- US projects. Ashrae 90.1 2007 refers to efficiencies determined at ARI conditions. I don't think it is necessary to be listed in ARI databse.

However, the problem is not only ARI conditions. For your project in Uruguay, you will have a different set of leaving chiller water temperature and entering condenser temperature to Table 6.8.l (which are say 6.7 deg C and 29.4 deg C respectively). Even if you manage to get the the supplier to provide the COP and IPLV/NPLV under the ARI condtions at the required leaving chiller water temperature at 6.7 deg C and extering condenser water temperature of 29.4 deg C, it is likely the COP will not meet the minimum.

However, page 32 of 90.1-2007 does state that these table values are only applicable over the following FULL LOAD design ranges:

Leaving chiller: 4.4 to 8.9 deg C
entering condenser: 23.9 to 29.4 deg C
condener-water temperature rise: 2.8 to 8.3 deg C

"Chillers designed to operate outide these ranges .........are not covered by this standard''

I would therefore believe that these equipments are not compliant to ashrae 90.1-2007, as outside the range does not default to compliance.

Dear guest experts,

What are your views to my thoughts posted above?

However, page 32 of 90.1-2007 does state that these table values are only applicable over the following FULL LOAD design ranges:

Leaving chiller: 4.4 to 8.9 deg C
entering condenser: 23.9 to 29.4 deg C
condener-water temperature rise: 2.8 to 8.3 deg C

"Chillers designed to operate outide these ranges .........are not covered by this standard''

I would therefore believe that these equipments are not compliant to ashrae 90.1-2007, as outside the range does not default to compliance

Thanks

Equipment does not have to be in the ARI database, but you should be able to demonstrate performance at ARI conditions.

I think we're largely arguing semantics here. If you've modeled the actual performance, and you are showing energy savings, my suspicion is that the LEED reviewers are pretty likely to accept it.

Christopher,

You are saying that there is a chance that when HVAC equipment do not meet 90.1, or not covered in 90.1, can still meet LEED pre-requsite. IF the energy model proves the energy saving required. This is interesting. I thought pre-requsite refers to the prescriptve and mandatory items. This makes a huge difference.

Not exactly. You have to meet the mandatory items. You don't have to meet the prescriptive items if you are running an energy model.

My point is, if you've got a piece of equipment that isn't listed, especially on a foreign project, but you can show that it has been modeled correctly and the model shows savings, I think the intent of the credit has been met.