Installation guide
Rinnai Continuous Flow Water Heating Specication Guide 02-13 | 7
Model selection - domestic applications
When specifying residential hot water applications there are some basic questions that
you need to ask in order to correctly design a system. You also need to bear in mind
future requirements of the building. The key point is water heating solutions should be
designed to the number of outlets and not people.
How many bathrooms?
A single bathroom home will
operate using the smaller Infinity
VT16 or VT20 unit, whereas a two
or three bathroom home will most
likely require the larger Infinity
VT26, HD200, HD250, or EF250
model.
Design of the house?
Where are the bathrooms and
other wet areas in relation to the
hot water system? The further
away the shower, the longer it will
take to get hot water. Typically if
an outlet is 15 m or greater you
could be looking at a time delay for
hot water of approximately 10-15
seconds. In most cases it is better
to site the Rinnai Infinity closer to
the kitchen sink where there is an
immediate demand for hot water.
If bathrooms are situated at
opposite ends of the house,
two Rinnai Infinity units may be
required.
How many people live in the
house?
The number of people living in the
house also needs to be considered.
As an example, you may have
a two bathroom home, with a
couple who rarely use the second
shower—an Infinity VT20 would
easily suffice. Similarly, the same
home could have Mum & Dad, and
three teenagers all fighting for two
showers in the morning meaning
a larger model Infinity would be
required.
Type of shower roses installed?
Typical flow rates for showers is
around 8-10 L/min, however there
is a large range of tapware on the
market with higher flow rates.
This needs to be factored when
determining the Infinity model
required.
To measure the flow rate of your
shower, hold a bucket under the
shower rose for one minute and
measure the volume.
Geographical location in New
Zealand?
Ambient water temperatures will
vary throughout the country, i.e.
South Island during winter will tend
to be much colder than the North
Island. This is important when
determining the incoming water
temperature and temperature
degree rise that is required as this
affects the output of the unit. Refer
to the New Zealand map below.
Positioning of the Infinity unit?
Siting of Rinnai Infinity units are
subject to installation clearances
which may affect positioning. Most
Rinnai Infinity units are positioned
externally with a range of options
for fixture to the outside of the
house, i.e. pipe cover so pipes can
be covered, unit can be secured
from theft with a security bracket,
or the unit can be recessed or
partially recessed so as to be
hidden from view. There are
however some instances where
internal units are more beneficial,
this application requires flueing
and is subject to some restrictions.
*RADIUS
Warm
Mild
Cool