Operating Instructions and Installation Instructions

VARINO GRANDE 350 - 600
We reserve the right to make changes to dimensions and construction 15 Edition 10.07.2015
© Copyright YGNIS AG CH-Ruswil
6.7. Hydraulic connection
6.7.1. General notice
For the hydraulic connection of the heating system and water heaters– in particular with regards to technical
safety devices such as safety valves, expansion tanks, etc. – refer to generally accepted engineering rules as
well as locally applicable standards, specifications and regulations.
If boilers are installed in garret-based heating plants or at the highest point of the heating system, then boilers
will have to be provided with additional safety devices (such as protections against water shortage). Observe the
minimum operating pressure as specified in chapter 4.4. Act in compliance with local safety regulations in force
at all times.
Boiler’s maximum operating pressure and the maximum operating temperature are given in chapter 4.1.
No minimum level of the amount of circulating water is required.
6.7.2. Water quality
Observe the required water quality according chapter 4.2. Anti-freeze should not be used.
Before connecting the boiler to an old installation, it is necessary to flush the whole heating system.
It is recommended to provide for a sludge separator.
Damage can occur from corrosion when oxygen continuously enters the heating water through open
installations, expansion tanks that are too small, floor heaters with pipe material that is not oxygen-tight, etc.
If this cannot be prevented, additional measures are necessary in the form of correctly used oxygen binding
agents or chemicals. If it is not possible to realize an installation without oxygen entrance, a system separation
must be set up using heat exchangers.
6.7.3. Boiler return flow
The condensing unit is fitted with a high temperature return flow in addition to the normal low temperature return
flow. Heating elements are connected to these with the maximum temperature level.
In order to ensure a high degree of efficiency of the boiler in each operating condition, care should be taken to
ensure that the low temperature return flow is supplied in each case.
It is not necessary to maintain the return flow temperature at a given level.
6.7.4. Draining the condensate
The condensates that result during condensation contain combustion products that are more or less acidic. Any
necessary approval for draining the condensate into the sewer system must be obtained from local authorities.
A condensate neutralisation set is available as an option, if desired
If the condensate is drained directly into the sewer system, then this must take place via an open funnel/hopper.
Important:
The recuperator is delivered with a siphon arranged in the casing. It must be ensured that no additional
siphon is installed since this would prevent the condensate from draining away. For the same reason, the
line to the funnel/hopper must have a slight gradient and should not show any slack!