10
WATER PIPING
HOTTER WATER CAN SCALD:
Water heaters are intended to produce hot water. Water heated to a
temperature which will satisfy space heating, clothes washing, dish
washing, cleaning and other sanitizing needs can scald and permanently
injure you upon contact. Some people are more likely to be permanently
injured by hot water than others. These include the elderly, children,
the infirm, or physically/mentally handicapped. If anyone using hot
water in your home fits into one of these groups or if there is a local
code or state law requiring a certain temperature water at the hot
water tap, then you must take special precautions. In addition to using
the lowest possible temperature setting that satisfies your hot water
needs, a means such as a *mixing valve, shall be used at the hot
water taps used by these people or at the water heater, see Figure 2.
Valves for reducing point of use temperature by mixing cold and hot
water are also available. Consult a Qualified Installer or Service
Agency. Follow manufacturer’s instructions for installation of the
valves. Before changing the factory setting on the thermostat, read
the “Temperature Regulation” section in this manual.
This water heater shall not be connected to any heating systems or
component(s) used with a non-potable water heating appliance.
All piping components connected to this unit for space heating
applications shall be suitable for use with potable water.
Toxic chemicals, such as those used for boiler treatment shall not be
introduced into this system.
When the system requires water for space heating at temperatures
higher than required for domestic water purposes, a tempering valve
must be installed. Please refer to Figure 2 for suggested piping
arrangement.
Water supply systems may, because of such events as high line
pressure, frequent cut-offs, the effects of water hammer among others,
have installed devices such as pressure reducing valves, check valves,
back flow preventers, etc. to control these types of problems. When
these devices are not equipped with an internal by-pass, and no other
measures are taken, the devices cause the water system to be closed.
INSTALLING THE NEW WATER HEATER
As water is heated, it expands (thermal expansion) and closed systems
do not allow for the expansion of heated water.
The water within the water heater tank expands as it is heated and
increases the pressure of the water system. If the relieving point of the
water heater’s temperature-pressure relief valve is reached, the valve
will relieve the excess pressure.
The temperature-pressure relief
valve is not intended for the constant relief of thermal
expansion.
This is an unacceptable condition and must be corrected.
It is recommended that any devices installed which could create a closed
system have a by-pass and/or the system have an expansion tank to
relieve the pressure built by thermal expansion in the water system.
Expansion tanks are available for ordering through a local plumbing
contractor. Contact the local water supplier and/or a service agency for
assistance in controlling these situations.
NOTE:
To protect against untimely corrosion of hot and cold
water fittings, it is strongly recommended that di-electric unions
or couplings be installed on this water heater when connected
to copper pipe.
FIGURE 9.
