Greenheck PVe (472846) - Manual (Page 11)

11 Model PVe Heat Recovery Unit
Piping Installation
Condensate Drain Trap
This unit is equipped with a stainless steel condensate
pan with a 1-inch MPT stainless steel drain connection.
It is important that the drain connection be fitted with a
P trap to ensure proper drainage of condensate while
maintaining internal static pressures.
A P trap assembly (kit) is supplied with each unit and
is to be assembled and installed as local conditions
require and according to the assembly instructions
provided with the P trap. If local and area codes
permit, the condensate may be drained back onto the
roof, but a drip pad should be
provided beneath the outlet. If
local and area codes require a
permanent drain line, it should
be fabricated and installed in
accordance with Best Practices
and all codes.
In some climates, it will be
necessary to provide freeze
protection for the P trap and
drain line. The P trap should be
kept filled with water or glycol solution at all times and
it should be protected from freezing to protect the P
trap from damage. If severe weather conditions occur, it
may be necessary to fabricate a P trap and drain line of
metal and install a heat tape to prevent freezing.
Unit Overview
Basic Unit
The units are prewired such that when a call for outside
air is made (via field supplied 24 VAC control signal
wired to unit control center), the supply and exhaust fan
are energized and optional motorized dampers open.
The unit is normally interlocked (24 volt) to the roof top
air handler. When the roof top air handler starts, the
auxiliary contactor in the air handler closes to start the
unit.
Summer Operation
Outdoor air is preconditioned (temperature is
decreased) by the transfer of energy from the cooler,
drier, exhaust air via the aluminum heat exchanger.
The preconditioned air is typically mixed with return air
going back to the air handler for final conditioning.
Winter Operation
Outdoor air is preconditioned (temperature is increased)
by the transfer of energy from the warmer, more humid
exhaust air via the aluminum heat exchanger. The
preconditioned air is typically mixed with return air
going back to the air handler for final conditioning.