Installation manual
12
ENVISION RESIDENTIAL INSTALLATION MANUAL
To maximize the benefits of the hot water generator a minimum 50-gallon water heater is recommended For higher
demand applications, use an 80-gallon water heater or two 50-gallon water heaters connected in a series as shown below.
Electric water heaters are recommended. Make sure all local electrical and plumbing codes are met for installing a hot
water generator. Residential units with hot water generators contain an internal circulator and fittings. A water softener is
recommended with hard water (greater than 10 grains or 170 total hardness).
Note: Under certain conditions, Envision dual capacity units operate with very low refrigerant discharge temperatures,
producing little or no water heating capability. This scenario occurs when the unit is operating with cold entering source
water (loop or well). Allowing the hot water generator pump to operate during these conditions actually removes heat
from the DHW circulating through the unit. To overcome this, Envision unit microprocessors have been programmed to
disengage the hot water generator pump during such conditions. (During low capacity cooling operation, the pump will
operate only if the DHW temperature entering the unit is less than the liquid line temperature plus 35° F. During high
capacity cooling operation, the pump will operate only if the DHW temperature is less than the liquid line temperature plus
60° F.) Using a preheat tank, as shown in Figure 12, will maximize hot water generator capabilities.
Figure 11: Typical Hot Water Generator Installation
CAUTION: Elements will burn out if energized dry.
Figure 12: Hot Water Generator Installation In Preheat Tank
In
Venting Waste Valve
or Vent Coupling
3/4" x 3/4" x 1/2"
tee
Cold
Water In
Hot
Water Out
P/T Relief
Valve
P/T Relief
Valve
DHW
Water In
DHW
Water Out
Drain ValveDrain Valve
Water Tank Preparation
To install a unit with a hot water generator, follow these installation guidelines.
Turn off the power to the water heater.1.
Attach a water hose to the water tank drain connection and run the other end of the hose to an open drain or outdoors.2.
Close the cold water inlet valve to the water heater tank.3.
Drain the tank by opening the valve on the bottom of the tank, then open the pressure relief valve or hot water faucet.4.
Flush the tank by opening the cold water inlet valve to the water heater to free the tank of sediments. Close when 5.
draining water is clear.
Disconnect the garden hose and remove the drain valve from the water heater.6.
Refer to Plumbing Installation and Hot Water Generator Startup.7.
NOTE: This configuration maximizes hot water
generator capability.
Drain Valve
In
P/T Relief
Valve
Cold
Water In
Hot
Water Out
DHW
Water In
DHW
Water Out
Venting Waste
Valve or Vent
Coupling
3/4 x 3/4 x 1/2 tee
Hot Water Generator Connections