Crestline BAS Specification / ASHRAE Guideline 13

CPC 604.1 / high-rise office Plumbing Specification

high-rise office specifications require Type L copper for above-floor domestic water piping. Type M has thinner walls and is not rated for the higher pressures found in high-rise buildings. Type K is required for underground installations.

CPC 814.0 / high-rise office Mechanical Specification

Direct connection to the sanitary sewer is not permitted for condensate drains, regardless of whether a P-trap is installed. CPC 814.0 requires condensate to discharge through an indirect waste connection. The high-rise office specification specifically requires the CRAC condensate to spill to a lavatory tailpiece, which provides a visible air gap and ensures the discharge is observable. A direct connection would hide any condensate flow problems and could allow sewer gas to reach the server room if the trap seal is lost. The visible spill point also serves as a diagnostic indicator — if the lavatory is constantly wet, maintenance knows the CRAC is producing excessive condensate.

Crestline BAS Specification

Despite the RTDs being more accurate, they do not meet the specification. The spec requires 10K ohm Type 2 thermistors, not RTDs. This is not about accuracy — it is about standardization and interchangeability. If the building uses 10K Type 2 thermistors throughout, any sensor can be replaced with any manufacturer's 10K Type 2 product without reprogramming the controller. RTDs have a different resistance curve, different wiring (often 3-wire or 4-wire vs. 2-wire), and require different analog input configuration. Mixing sensor types creates a maintenance nightmare.

Crestline BAS Specification / ASHRAE Handbook — Fundamentals

The probe insertion is inadequate. At 6 inches into a 36-inch duct, the probe extends only 17% into the duct width — well short of the required 25-50% (which would be 9-18 inches). A shallow probe reads the boundary layer temperature near the duct wall, which is influenced by heat gain or loss through the duct wall and does not represent the bulk airstream temperature. For a 36-inch duct, the probe should extend at least 9 inches (25%) and ideally 12-18 inches (33-50%) to read the core airstream temperature accurately.

Crestline Diffuser Schedule / SMACNA

The EA6X6 grille is rated for only 100 CFM per the Crestline schedule. Installing it on a 200 CFM exhaust point doubles the design velocity through the neck, creating excessive noise (well above NC-35 criteria for occupied spaces) and pressure drop far exceeding the 0.15" WG maximum. The correct grille is EA8X8-200, which has an 8"x8" neck sized for 200 CFM. Undersized grilles also cause the exhaust fan to work harder, increasing energy consumption and reducing fan life.

Crestline Electrical Specification (THD ≤ 3%; cf. IEEE 519-2022 Table 2)

The Crestline electrical specification caps total harmonic (voltage) distortion (THD) at the point of common coupling at 3% — stricter than the IEEE 519-2022 Table 2 voltage-distortion limits of 5% (1–69 kV) / 8% (≤1 kV total), where 3% is the individual-harmonic limit. At 4%, the installation exceeds the project's 3% cap. An active harmonic filter or multi-pulse drive configuration is required to bring THD into compliance.