Maintenance
8
3.1.2 Water Venturi System for Pools and Some Large Spas (Not Included or Sold by Viqua)
A venturi draws air by forcing a set amount (or flow rate) of water through a pipe that gradually reduces in size and at the
smallest point in the pipe the venturi action (or air suction) is created. A venturi or venturi system (Refer
) must be
selected to match the pump flow. Install the venturi on the discharge side of the pump and after the filter. On large
systems, the venturi may create an unacceptable pressure drop, if so, a by-pass ball valve or spring loaded check valve
can be installed. To increase the draw with a venturi system that incorporates a ball valve, simply adjust, or slowly close
the ball valve. This will create a back pressure in the bottom pipe (Refer
) which will force water up to and through
the venturi, thereby increasing draw (or suction). A spring loaded by-pass check valve is suggested for two speed pump
systems (usually used on spas) to provide an automatic flow adjustment. It is recommended to install a venturi system
(e.g. Mazzei injector) with a flow rating of 20 gpm for 1" pipework and 60 gpm for 1.5" pipework with a 5 psi pressure drop.
A ball valve by-pass is required for flows over the rated flow of the venturi. A ball valve by-pass venturi system (Refer
) is recommended for any pool installation, to offer a full range of adjustability.
Examples of Venturi Installations
Section 4
Maintenance
Regularly inspect your ozone generator unit to ensure that the lamp is still working.
The ultraviolet output of the UV lamp gradually reduces with usage. However, there is a wide variation in the actual amount
of ozone required because of differences in the volume of water and the number of people using the hot tub or spa. The
condition of the water is a reasonable indicator to tell when a new lamp or maintenance is needed. A large increase in the
amount of treatment chemical or a change in the water color or scum on the inside of the tub are all indications that more
ozone is required. As dust on the lamp will also reduce output, the lamp should be cleaned first to verify that the lamp needs
to be replaced (Refer
). As a general guide, lamp replacement is suggested after 12 to 18 months of continuous
operation.
Figure 3
Figure 3 Examples of Venturi Installations
WA R N I N G
•
Always disconnect power before performing any work on the UV system.
•
Always shut-off water flow and release water pressure before servicing.
•
Regularly inspect your UV system to ensure that the power indicators are on and no alarms are present.
•
Replace the UV lamp annually (or biennially if seasonal home use) to ensure maximum performance.
•
Always drain the chamber when closing a seasonal home or leaving the unit in an area subject to freezing temperatures.
check valve
check valve
3/8" tube coming
from ozone generator
return water line
to pool
return water line
to pool
ball valve
(please note open & closed
positions for handle assembly)
water line from pump
heater and filter
water line from pump
heater and filter
Parts List
Parts List
venturi assembly (with valve)
check valve
hose clamp
12’ of 3/8" ID hose
venturi only
check valve
PVC pipe
hose clamp
3/8" tube coming
from ozone generator
open position
closed position
Venturi
Venturi
