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Heating system volume (l)
Expansion tank full volume (L)
Starting pressure in the expansion tank
User’s and technical staff manual
Membrane expansion tanks have nipple apertures which serve for regulating and monitoring of pressure’s
values in the gas part of the vessel. After you define the initial pressure, it is necessary to measure the pressure
in the gas part of the tank (for instance; by the car pressure gauge) and then release or add (for instance; by the
car pump) the air up to the set pressure value. Simultaneously you should consider that for the boilers BaltGaz
NEVALUX the initial pressure in the expansion tank should be at least 0,1 MPа and not more than 0,3 MPа.
Lower pressure can cause the boiler’s operating failure.
To calculate the full volume of the expansion tank you can use the following formula:
Vc =1,099*Vi*Av*(Рmах +0,1) / (Рmах – Р),
where:
Vi – full volume of heating system in litres;
Av – growth of water volume in the heating system from the expansion at heating up to the maximal
possible temperature;
Рmах=0,3 MPа – maximal calculated pressure in the expansion tank (equals to the pressure of the safety
valve activation);
Р – initial pressure in the expansion tank (calculated according to the above mentioned method).