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PLUMBING CONNECTION
WINTER 2016
CHOOSING THE RIGHT WATER
HEATING SYSTEM
GENERAL PRINCIPLES
Commercial & Institutional
Commercial and institutional heating systems serve the
same purpose as a domestic water heater but in much larger
quantities required by commercial facilities such as hotels,
apartments, motels, guest houses, schools, commercial
laundry facilities, office amenities and canteens etc.
Industrial
These systems cover more specialised applications where
heated water is used for mixing, heating, sterilising and
other similar requirements.
SELECTION GUIDELINES
To decide on the water heating system to recommend and
install, follow these steps:
1. Determine the peak demand period for the application and
energy type to be used for the system
2. Calculate the hot water requirements over the peak period
relating to volume and temperature
3. Select the water heaters that will meet the demand
calculations as per individual system specifications
4. Ensure adequate space is available for the installation of a
commercial plant – it will require a footprint to fit but also
sufficient area available for maintenance and service
5. For an effective and efficient system, correct pipe sizes
are required for cold water supply, heated water delivery
and the gas fitting line in the case of a natural or propane
system.
SYSTEM SUITABILITY = ASKING THE QUESTIONS
If the commercial application is an existing facility and
there is the opportunity to meet with the occupants and
discuss heated water for their daily business needs then
it can be very advantageous to not only ask the owner of
the business but also the key staff who actually use heated
water fixtures to perform their work activities. Kitchen
hands and waiters are good examples.
A good example of this procedure is if a restaurant is
seeking to upgrade the hot water system. It isn’t the number
of seats in the restaurant but the number of meals on their
busiest day of the week that the system needs to be capable
of delivering to. You need to think of the highest usage
pattern experienced during the peak demand period.
Once the number of meals is correctly ascertained then
refer to the associated sizing guide to determine the type
of meal service facility and match the allowances per meal
being prepared (i.e. 3.1 litres or up to 5.5 litres for a three
course meal).
Then confirm the temperature necessary to service the
fixtures being used for washing up.
Most municipal councils require a minimum of 77˚C water
supply at a scrub sink area; there is also a preference for
“commercial” temperature hot water if a floor is being hosed
down after a shift to remove surface debris and grease.
Finally, check that the system to be installed will actually
deliver the desired temperature as most domestic hot
JON PALFREY
DISCUSSES THE KEY FACTORS USED TO DETERMINE WHICH WATER HEATING SYSTEM IS MOST
APPROPRIATE FOR COMMERCIAL AND INDUSTRIAL APPLICATIONS.
HOT WATER CLINIC
JON PALFREY