mundoclima AEROTHERM MAM-V9 Serie Manual De Usuario E Instalacion página 128

Before continuing installation of the unit, check the following:
7KH PD[LPXP ZDWHU SUHVVXUH ”  EDU
7KH PD[LPXP ZDWHU WHPSHUDWXUH ” ƒ& DFFRUGLQJ WR VDIHW\ GHYLFH VHWWLQJ
Always use materials that are compatible with the water used in the system and with the materials used in the unit.
Ensure that components installed in the field piping can withstand the water pressure and temperature.
Drain taps must be provided at all low points of the system to permit complete drainage of the circuit during maintenance.
Air vents must be provided at all high points of the system. The vents should be located at points that are easily accessible
for service. An automatic air purge is provided inside the unit. Check that this air purge valve is not tightened so that
automatic release of air in the water circuit is possible.
9.4.2 Water volume and expansion vessel pre-pressure checks
The units are equipped with an expansion vessel (5/7/9kW models:2L; 12/14/16kW models:5L) that has a default pre-pressure
of 1.5 bar. To assure proper operation of the unit, the pre-pressure of the expansion vessel might need to be adjusted.
1) Check that the total water volume in the installation, excluding the internal water volume of the unit, is at least 25L(for 5/7/9
kW unit, the minimum volume is 15L) . Refer to 14 Technical specifications to find the total internal water volume of the unit.
In most applications this minimum water volume will be satisfactory.
In critical processes or in rooms with a high heat load though, extra water might be required.
When circulation in each space heating loop is controlled by remotely controlled valves, it is important that this
minimum water volume is kept even if all the valves are closed.
2) Using the table below, determine if the expansion vessel pre- pressure requires adjustment.
3) Using the table and instructions below, determine if the total water volume in the installation is below the maximum allowed
water volume.
Installation
height
Water volume
difference(a)
12 m No pre-pressuread justment required.
Actions required:
‡ 3UHSUHVVXUH PXVW EH LQFUHDVHG FDOFXODWH
according to
"Calculating the pre-pressure of the expansion
>12 m
vessel" below.
‡ &KHFN LI WKH ZDWHU YROXPH LV ORZHU WKDQ PD[LPXP
allowed water volume (use graph below)
Heighe difference is between the highest point of the wateer circuit and the outdoor unit's expansion tank. Unless the unit is
located at the highest point of the system, in which case the installation height differnce is considered to be zero.
For 1-phase 12~16kW and 3-phase 12~16kW units, this value is 72L, for 5~9kW units, this value is 30 L.
Calculating the pre-pressure of the expansion vessel
The pre-pressure (Pg) to be set depends on the maximum installation height difference (H) and is calculated as follows:
Pg(bar)=(H(m)/10+0.3) bar
Checking the maximum allowed water volume
To determine the maximum allowed water volume in the entire circuit, proceed as follows:
NOTE
72 L(b)
Actions required:
‡ 3UHSUHVVXUH PXVW EH LQFUHDVHG FDOFXODWH
according to
"Calculating the pre-pressure of the expansion
vessel" below.
‡ &KHFN LI WKH ZDWHU YROXPH LV ORZHU WKDQ
maximum allowed water volume (use graph below)
Expansion vessel of the unit too small for the
installation.
125
Water volume >72 L(b)