EER

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Where in eQuest can you assign an EER of a DX coil or the Efficiency of a furnace?

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JAMES HURLEY

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You assign the cooling EIR (inverse of COP) under system>cooling>unitary power. Technically, you should define the efficiency of the compressor separately from the fan power, otherwise eQUEST will double-count the fan energy. If you use an overall system EER, then you should set the fan power (kW/cfm) to zero.

Furnace efficiency (heat input ratio) is specified under system>heating>unitary power.

Kelsey Van Tassel

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James,

Kelsey's right - in detailed mode such efficiency measures entered in
wizard mode get split into fan energy (kW/CFM) and heating (EIR/HIR) &
cooling (EIR) efficiencies. If entering values for heating/cooling
efficiency - pay mind to whether fan energy is included in your EER
figures (it usually is), and follow Kelsey's advice to zero out the fan
energy if so.

If you're not in detailed yet, heating and cooling efficiencies are
handled most simply using Wizard Screen 3 of ##:

~Nick

NICK CATON, E.I.T.

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James:

If you are modeling to 90.1-2007 Appendix G, then you need to breakout the fan
energy, so you cannot set it to 0 as suggested. See G3.1.2.1.

Paul Diglio

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Good catch Paul! A lot of my modeling of late has been outside 90.1 so my head?s not totally in the game =).

Attached is a potentially helpful resource I grabbed from the lists at some point that I?ve referenced for breaking EER into cooling EIR / fan energy, if you?re modeling under such constraints or otherwise wish to separately model fan energy.

There?s more like this to be found in attachments and discussions in the archives.

I?ve taken zeroing out the fan energy and using listed COP/EER figures for EIR?s as an appropriate method for exploring various packaged equipment options, acknowledging those figures account for associated fan energies, but Paul?s right in that you wouldn?t want to do this for an Appendix G performance rating.

~Nick

NICK CATON, E.I.T.

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Thanks Nick, that is a helpful document.

Paul

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