Crestline Piping Specification / Victaulic Installation Guide

Crestline Mechanical Specifications / ASME B31.9

Ball valves are not permitted underground per the Crestline specifications. All underground valves must be gate valves. Gate valves are preferred underground because they provide a full-port opening with minimal pressure drop when fully open, and their rising stem or position indicator makes it easy to verify valve position from above the valve box. Ball valves underground are problematic because the handle position can be ambiguous through a valve box access, and ball valve seats can be damaged by debris common in underground installations. The ball valve must be replaced with a gate valve of the same size and pressure rating.

Crestline Mechanical Specifications / Site Plan

This installation is correct. Per the Crestline plans, all underground piping not directly outside the central plant is rated for 140 degrees F. The 180 degrees F rating is only required for piping immediately outside the central plant where water temperatures are highest. Building-to-building distribution piping at 140 degrees F rating is appropriate because water temperature drops through the distribution network. The 36" cover also meets the minimum burial depth requirement specified on the detail sheet.

Crestline Piping Specification / ASTM B88

Type M copper is NOT acceptable for pressure water piping per the project specification. Type M has the thinnest wall of the three copper tube types (K, L, M) and does not provide adequate long-term reliability for commercial pressure water service. Type L is the minimum required for above-ground pressure water piping, and Type K is required for underground or high-pressure applications. While Type M may be allowed by some residential codes, commercial specifications almost universally prohibit it for pressure service due to its susceptibility to erosion corrosion and pinhole leaks over time.

Crestline Plumbing Specification (gear operators required on 6 in. and larger)

Butterfly valves 6 inches and larger must be equipped with a gear operator, not a lever handle. Lever handles on large valves allow rapid closure that causes water hammer, and they cannot provide the fine control needed for balancing. Gear operators also prevent unauthorized operation.

Crestline Plumbing Specification / ASME B16.34

Valves must be rated to exceed the maximum operating pressure by at least 50% per Crestline specifications. A 100 psi rated valve on a 125 psi system is under-rated and risks catastrophic valve body failure. A minimum 200 psi rated valve (Class 150) is required.

Crestline Seismic Specification

This is correct. Per Crestline spec, in-line duct equipment weighing 75 pounds or less is considered seismically braced by the duct system itself, provided it is rigidly attached to the duct. At 65 pounds, the humidifier is under the 75-pound threshold. The duct's own seismic bracing (transverse at 30 ft max, longitudinal at 60 ft max) provides adequate restraint for the lightweight equipment. If the humidifier exceeded 75 pounds, it would require independent seismic supports regardless of its duct connection.