#1348 DHW Error in EAA for Propane + type ElecResistance / Consumer Instantaneous (UEF).

[Thao Chau]

Error is thrown for an EAA project with Fuel = Propane, DHW = altered, type ElecResistance / Consumer Instantaneous (UEF).
Solution: update Std design to be ElecResistance

[Alea German]

Std Design should only be ElecRes if the existing conditions are verified and the existing water heater is ElecRes.

Other updates to Standard Design water heating:
When existing conditions are verified update ruleset for altered water heaters to apply the existing water heater specifications to the Standard Design (see files #21 and #22).

When existing conditions are not verified, the ACM is not clear on what is intended for the Standard Design for altered water heaters. ACM specifies “Existing fuel type, proposed tank type”. In these situations, the existing fuel type is unknown. Suggest changing this to “Proposed fuel type”, in which case the ruleset should be updated to reflect an electric water heater in the Standard Design when the Proposed has an electric water heater. Clarify the type of water heater to apply in the Standard Design for electric water heaters. Should it be electric resistance or a HPWH?

[Scott Criswell]

ruleset mods addressing these EAA DHW standard design issues checked into SVN @ r2382

• prevent fuel switching from Proposed to Std for Altered DHW heaters
• ensure altered w/ verified existing DHW systems use existing system & heater(s) in std design
• ensure fully defaulted/specified std design DHW systems in Altered analysis
• all proposed altered electric (HPWH or resistance) systems modeled as HPWH in std design (based on ticket guidance (above), RACM not clear here)