Drazice NADO 500/200v7, NADO 750/200v7, NADO 1000/200v7 Operation And Installation Manual

Operation and Installation Manual

Accumulation Tanks

NADO 500/200v7
NADO 750/200v7

NADO 1000/200v7

Družstevní závody Dražice-strojírna s.r.o.

(Works Cooperative - Dražice – Machine Plant, Ltd.)

Dražice 69

294 71 Benátky nad Jizerou

Tel.: [phone], fax: [phone]

www.dzd.cz
[e-mail]

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1. Description

Accumulation tanks serve accumulation of excessive heat from its source. The source may be a

solid fuel boiler, heat pump, solar collectors, fireplace inserts, etc. Some types of tanks allow
combination of connecting even multiple sources.

The NADO type tanks serve accumulation of heat in the heating system and allow heating or
preheating of HSW (Hot Service Water) in an inner tank. Incorporation of an accumulation tank in the
heating system with a solid fuel boiler allows an ideal run of a boiler at favourable temperature during
the boiler operation. The main benefit lies in the period of optimum operation (i.e. with maximum
efficiency) when the excessive unconsumed heat accumulates in the tank.

The tanks and tubular exchangers are made of steel, without the inner surface treatment, the outer
surface of the tank is provided with a protective paint. The tanks are manufactured in 500, 750 and
1000-litre volumes. The 500-litre version is additionally equipped with a tubular exchanger of 2.5m

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surface and the 750 and 1000 litre version with a tubular exchanger of 3.3 m2 surface and two funnels
G1½“ mm, with the possibility to install an electric heating element of TJ 6/4“ series with an extended
cooling compartment, up to 6 kW.

The NADO type enables direct heating of HSW (Hot Service Water) in an inner enamelled tank,
or preheating of water for another water heater. Connection to a boiler usually allows direct HSW
heating in an inner tank to the desired temperature whilst, on the contrary, connection to solar
collectors or heat pump only preheats HSW and another, e.g. electric, heater has to be used, in order to
reheat the water to the desired temperature, or final electric reheat has to be fitted in the accumulation

tank which is enabled by a TJ 6/4“ series electric heating unit with an extended compartment of up to

6 kW output.

2. Designing the size and connection of ACCU tank to the heating system

An ideal size of the accumulation tank is designed by a design engineer, or a person sufficiently
qualified to design heating systems.
Product assembly must be implemented by an authorised person (confirmed in the warranty
certificate).

Important: When putting into operation, water has to be filled first into the inner tank for HSW
and the operating pressure inside it has to be kept, only then heating water can be filled into the
outer accumulation tank, otherwise the product may get damaged!

The manufacturer explicitly emphasises the necessity of being particular in testing the tightness
of the heating circuit (radiators, piping joints, floor heating, etc.) with the connection of the
accumulation tank. No pressure grow in the accumulation tank heating water compartment
may occur above the maximum operating pressure of 0.3 MPa, if the heating system is
pressurised to higher than the maximum operating pressure, the inner enamelled tank may get
permanently damaged!

No stop fitting can be put between the security fitting of the heating circuit and the accumulation
tank!!