Specifications

ENVISION COMMERCIAL SPECIFICATION CATALOG

Water Piping

Piping is usually design as ‘reverse return’ to equalize flow

paths through each unit. A short flexible pressure rated

hose is used to make connection to the fixed building

piping system. This hose is typically stainless steel braid

and includes a swivel fitting on one end for easy removal

and is flexible to help isolate the unit for quieter operation

. Isolation valves for servicing, y-strainers for filtering

and memory-stop flow valve or a balancing valve can be

provided for consistent water flow through the unit.

All unit source water connections are fittings that accept

a male pipe thread (MPT). Insert the connectors by

hand, then tighten the fitting with a wrench to provide

a leakproof joint. The open and closed loop piping

system should include pressure/temperature ports for

serviceability. The proper water flow must be provided to

each unit whenever the unit operates. To assure proper

flow, use pressure/temperature ports to determine the

flow rate. These ports should be located at the supply

and return water connections on the unit. The proper

flow rate cannot be accurately set without measuring the

water pressure drop through the refrigerant-to-water heat

exchanger. Never use flexible hoses smaller than 1˝ inside

diameter on the unit. Limit hose length to 10 feet per

connection. Check carefully for water leaks.

Condensate Drain

On vertical units, the internal condensate drain assembly

consists of a drain tube which is connected to the drain

pan, a 3/4˝ PVC female adapter and a flexible connecting

hose. The female adapter may exit either the front or

the side of the cabinet. The adapter should be glued to

the field-installed PVC condensate piping. On vertical

upflow units, a condensate hose is inside all cabinets as a

trapping loop; therefore, an external trap is not necessary.

On horizontal units, a PVC stub is provided for condensate

drain piping connection. An external trap is required (see

below). If a vent is necessary, an open stand pipe may be

applied to a tee in the field-installed condensate piping.

Envision Application Notes cont.

1.5 in.

3/4 in. PVC tube stub

3/4 in. PVC

Coupling

Vent (if needed)

3/4 in. PVC

1/8 in. per foot