FI-VED - open expansion tank FI-VED - open expansion tank

FI-VED - open expansion tank

General issuesa

- the open expansion tank is a safety element of the heating plants, especially for those operating on solid fuel.
- The expansion tank in a system has the following two roles: to take over the volume variations of the heating water caused by the changes of temperature, namely to ensure a water reserve for the smooth operation of the system;
- From the construction point of view, the FI-VED expansion tank is a steel cylinder-shaped tank having defined capacity, equipped with 4 threaded connections: turn connection, return connection, heating water level connection, down flow and back water connection.
- The open expansion tank shall be assembled in the highest point of the system, in vertical position and as closed as possible to the vertical axis of the boiler. The bottom of the expansion tank must exceed the highest level of the system by at least 1.5 meters. The connection must be directly to the turn pipe of the boiler without closing elements between the turn of the boiler and the tank. On the return pipe of the expansion tank you can assemble an adjustment valve for the adjustment of the water circulation into the expansion tank.
- The expansion tank shall be heat insulated and protected against freezing.
- The open expansion tank is absolutely necessary in the systems with gravitational circulation.

Specifications

MODEL UM FI-VED 28 FI-VED 40 FI-VED 60 FI-VED 80 FI-VED 100 FI-VED 150 FI-VED 250
Tank volume L 28 40 60 80 100 150 250
Diameter without insulation D mm 320 320 320 400 400 475 550
Height without insulation Ht mm 390 540 790 700 870 900 1110
Weight kg 11 14,4 20 23 27,5 34,5 60
Turn connection RT toli 1” ext 1” ext 1” ext 1” ext 1” ext 1” ext 1½”ext
Return connection RR toli ½” ext ½” ext ½” ext ½” ext ½” ext ½” ext ½” ext
Water level connection N țoli ½” ext ½” ext ½” ext ½” ext ½” ext ½” ext ½” ext
Down flow connection PP toli 1” ext 1” ext 1” ext 1” ext 1” ext 1” ext 1½”ext
Open expansion tank
RT. Turn connection
RR. Return connection
N. Heating water level connection
PP. Down flow, back water connection

Possible connection schemes

The hydraulic connections schemes of a boiler with open expansion tank
The hydraulic connections schemes of a boiler with open expansion tank

If there is no permanent water source (even if a house water supply plant is being used), the installation option of a boiler operating on solid fuel shall mandatory be an open system with open expansion tank.
We recommend the use of the open expansion tank even if the system operates on the grounds of the thermo-siphoning principle.
The safety valve on the boiler is mandatory in each assembly system.
To extend the life cycle of the boiler by avoiding condensation and cheaper operation we recommend the assembly between the turn and the return of a thermostat-controlled recirculation pump. .

SS - safety valve
S - heat valve probe
VED - open expansion tank
RI - radiator
A - airing device
R - return inlet
T - turn inlet
SI – plug cock
Pc - circulation pump
Cs1 - way valve
GC - boiler discharge
ARM - household hot water
ACM - Household cold water
ARR - cold water from the network
RST - heat valve connection
Prc - recirculation pump
Cs2 - way valve
Ts - Prc pumps control thermostat
Fy - impurities filter