Envision Peripherals R-410A installation manual Desuperheater Connections, Water Tank Preparation

ENVISION RESIDENTIAL INSTALLATION MANUAL

Desuperheater Connections

To maximize the benefits of the desuperheater 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 desuperheater. Residential units with desuperheaters contain an internal circulator and fittings.

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 desuperheater 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 desuperheater 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 35º F. During high capacity cooling operation, the pump will operate only if the DHW temperature is less than the liquid line temperature plus 60º F.) Using a preheat tank, as shown in Figure 12, will maximize desuperheater capabilities.

Water Tank Preparation

To install a unit with desuperheater, follow these installation guidelines.

1.Turn off the power to the water heater.

2.Attach a water hose to the water tank drain connection and run the other end of the hose to an open drain or outdoors.

3.Close the cold water inlet valve to the water heater tank.

4.Drain the tank by opening the valve on the bottom of the tank, then open the pressure relief valve or hot water faucet.

5.Flush the tank by opening the cold water inlet valve to the water heater to free the tank of sediments. Close when draining water is clear.

6.Disconnect the garden hose and remove the drain valve from the water heater.

7.Refer to Plumbing Installation and Desuperheater Startup on page 12.

CAUTION: Elements will burn out if energized dry.

Figure 11: Typical Desuperheater Installation

3/4 x 3/4 x 1/2 tee	Cold	Hot
	Water In
		Water Out
Venting Waste
Valve or Vent
Coupling

DHW

Water Out

P/T Relief

Valve

In

DHW
Water In	Drain Valve

Figure 12: Desuperheater Installation In Preheat Tank

Venting Waste Valve	3/4" x 3/4" x 1/2"	Cold		Hot
or Vent Coupling	tee	Water In	Water Out

	DHW
	Water Out
	P/T Relief	P/T Relief
	Valve	Valve
	In
DHW	Drain Valve	Drain Valve
Water In

Note: This configuration maximizes desuperheater capability.

11