User manual

FAQ for CBECC-Res 2013

apply to existing systems. It is the labels in the fields that contain an overview of the system (HVAC –

DISTRIBUTION SYSTEMS, HVAC - FAN SYSTEMS) that may still reference HERS requirements. The

CF1R was recently changed to remove sections that do not apply. If registration is required (for

example, duct testing for greater than 40 feet of new duct), no HERS verifications are triggered for

the existing HVAC system or IAQ for an addition < 1,000 ft

3. If I have an Addition Alone, can I use the same exceptions mentioned in Question 5 from July 17 to

prove to the building department that I do not need to register my CF1R?

Yes. Until staff can come up with a solution for identifying that an addition meets the conditions for

not requiring registration and not producing the watermark, you will need to be prepared to prove

to the building department that registration is not required. For that you can consult FAQ #5 from

July 17 for more information, based on Section 150.2 of the Building Energy Efficiency Standards.

4. I switched a file from Addition and/or Alteration to Addition Alone and now it will not run (the

error says the HVAC system is invalid). What do I need to do?

Most likely, you had an existing HVAC system defined to serve the addition zone and when you

switched it to Addition Alone, the status field disappeared while it was set to “existing.” To fix this

(a) switch the Run Scope (Analysis tab) back to Addition and/or Alteration, (b) go back to the zone

and set the HVAC System Status to “New”, (c) switch the Run Scope back to Addition Alone, and (d)

define an HVAC system status that is recognized by the program (the system that was previously

defined is an “existing” system). The HVAC system, assuming it is an existing system, should look

exactly like a prescriptive system—78% AFUE, split system cooling with 13 SEER and 11.3 EER (or if

2015 compliance 14 SEER and 11.7 EER), with Refrigerant Charge set to match Package A from

Section 150.1.

5. Why are there HERS requirements when I modeled “No Cooling”?

No cooling is modeled in such a way as to have no effect on compliance (no credit, no penalty) by

simulating a cooling system equivalent to the prescriptive requirements for the specified climate

zone in both the Standard and Proposed Design. The CF1R was reporting what was modeled,

including the system efficiency, mandatory requirements for airflow of > 350 CFM/ton of cooling

and fan efficacy of < 0.58 W/CFM, in addition to the prescriptive requirement for refrigerant charge.

When the system works as desired, the HERS requirements may appear along with the system type

“No Cooling” and the builder will confirm that no cooling was installed when completing the CF2R-

MCH-01-H (Space Conditioning Systems, Ducts, and Fans). A HERS rater will not perform tests on a

non-existent system. However, if a cooling system is installed, a new CF1R must be uploaded to the

HERS provider changing the “NoCooling” system type to the appropriate system type and features,

and all of the mandatory requirements will apply, as well as any HERS verified features.

6. Although I specify default values for roof reflectance, the CF1R is reporting non-standard roof

reflectance and a cool roof. How can I fix this?

As of July 23, if you model 0.1 roof reflectance the CF1R will correctly report if there is or is not a

cool roof. The special feature reporting of a non-standard value cannot be fixed until Version 3 of

the program is approved. If the special feature message is bothersome, model a roof reflectance of

0.099 which is below the trigger point (this will have a slight effect on the cooling compliance).

When corrected, a value of > (greater than) 0.1 but < (less than) 0.2 will be reported as a non-

standard roof reflectance. A cool roof will only be set to yes when the roof reflectance is > (greater

than or equal to) 0.2.