Družstevní závody Dražice - strojírna s.r.o.

1. Description of Accumulation Tanks

Dražice NAD series accumulation tanks are designed for storing excess heat from a heat source, such as solid fuel boilers, heat pumps, solar collectors, or fireplace inserts. They are primarily used for heat storage within heating systems. The tanks are manufactured from steel with an external protective coating and feature removable 80 mm NEODUL LB PP insulation. They are available in volumes of 500, 750, and 1000 liters. Certain versions are equipped with one or two internal pipe heat exchangers (1.4 m² each) and an inspection aperture (182 mm diameter) for installing an electric heating unit (TPK). These tanks are not intended for storing domestic hot water (DHW).

2. Basic Dimensions

3. Description of Individual Versions (NAD v1-v5)

The NAD series includes several versions differing in their connection configurations:

• NAD v1: Features one to three flanges. The 210 mm bolt circle flange is for mounting a TPK flange electric heating unit. A G 6/4" connection pipe can be used for a TJ G 6/4" electric heating unit. The flange is blanked off in the standard version.
• NAD v2: Equipped with a G 6/4" connection pipe, suitable for mounting a TJ G 6/4" electric heating unit.
• NAD v3: Offers a 210 mm bolt circle flange and connection pipes, or only connection pipes. The 210 mm flange is for TPK mounting and is blanked off in the standard version.
• NAD v4: Features a 210 mm flange for TPK mounting and one 1.4 m² heat exchanger for connecting an additional heating system (e.g., SOLAR). The flange is blanked off in the standard version.
• NAD v5: Features a 210 mm flange for TPK mounting and two 1.4 m² heat exchangers for connecting additional heating systems (e.g., SOLAR). The flange is blanked off in the standard version.

4. Illustrations of NAD Versions

Diagrams show the different NAD models (v1 to v5) with numbered connection points:

NAD v1

Connections: 1. Inlets for water to storage tank (internal G 5/4") 3. Outlet for storage tank (air outlet) (external G 1") 4. Other outlet (internal G 5/4") 5. Water inlet to storage tank (discharge) (external G 1") 6. Wells for sensors (thermometer, thermostat) (internal G 1/2") 7. Water outlet from storage tank (return water) (internal G 5/4") 8. Flange with screw gauge 210 for TPK mounting 11. Possibility for mounting TJ 6/4" el. heating unit

NAD v2

Connections: 1. Inlets for water to storage tank (internal G 5/4") 3. Outlet for storage tank (air outlet) (external G 1") 5. Water inlet to storage tank (discharge) (external G 1") 6. Wells for sensors (thermometer, thermostat) (internal G 1/2") 7. Water outlet from storage tank (return water) (internal G 5/4") 11. Possibility for mounting TJ 6/4" el. heating unit

NAD v3

Connections: 1. Outlets (inlets) for water to storage tank, possibility of mounting TJ 6/4" el. heating unit 3. Outlet for storage tank (air outlet) (external G 1") 6. Wells for sensors (thermometer, thermostat) (internal G 1/2") 8. Flange with screw gauge 210 for TPK mounting

NAD v4 (bottom heat exchanger only) / NAD v5 (both heat exchangers)

Connections (common for v4 & v5): 1. Inlets for water to storage tank (internal G 5/4") 3. Outlet for storage tank (air outlet) (external G 1") 4. Other outlet (internal G 5/4") 5. Water inlet to storage tank (discharge) (external G 1") 6. Wells for sensors (thermometer, thermostat) (internal G 1/2") 7. Water outlet from storage tank (return water) (internal G 5/4") 8. Flange with screw gauge 210 for TPK mounting 9. Inlet for heating water (external G1") 10. Outlet for heating water (external G1") 11. Possibility for mounting TJ 6/4" el. heating unit

5. Technical Parameters

General Parameters: Maximum operating pressure in the tank: 0.3 MPa Maximum temperature of heating water in the tank: 90 °C

For versions 4 and 5: Maximum operating pressure in the heat exchanger: 1 MPa Maximum temperature of heating water in the heat exchanger: 110 °C

Operating Conditions: Recommended for indoor use with air temperature between +2 °C and +45 °C. Maximum relative humidity: 80%. No shut-off valve is permitted between the heating circuit safety fitting and the accumulation tank.

6. Heat Insulation

The tanks are equipped with removable 80 mm thick NEODUL LB PP insulation. This includes the top cover, flange covers, and opening caps. The insulation is supplied separately. It is recommended to install the insulation at room temperature. Temperatures significantly below 20 °C may cause the insulation to shrink, hindering installation.

7. Product Information Sheet Summary

Key technical data for different models:

NAD 500 Series

NAD 750 Series

NAD 1000 Series