ECO ULTRA Electric Boiler
Installation, Use and Care Manual
(Revision June 2017)
, Page
35.
DOMESTIC HOT WATER TEMPERATURE
& PRESSURE RELIEF VALVE
An automatic temperature & pressure relief valve
with a temperature probe of sufficient length must
be installed at the time of the installation. No valve
of any type should be placed between the T&P
relief valve and the water heater. Use a tee to
install the relief valve onto the hot water outlet. The
pressure rating of the relief valve must not exceed
150 psi.
The BTU per hour rating of the relief valve must
equal or exceed the BTU per hour input of the
boiler(s) or heat source(s) as marked on the
boiler(s) rating plate.
For a circulating tank installation, the separate
storage tank(s) must have similar protection.
Connect the outlet of the relief valve to a suitable
open drain, so discharge ca
n exit only 6” above the
structural floor; and cannot contact any live
electrical parts. The discharge line must pitch
downward from the valve to allow complete
draining (by gravity) of the relief valve and
discharge line, and be no smaller than the outlet of
the valve. The end of the discharge line should not
be threaded or concealed and should be protected
from freezing. No valve of any type, restriction or
reducer coupling should be installed in the
discharge line. Local codes shall govern the
installation of relief valves.
THERMOSTATIC MIXING VALVE
When this water heater is supplying general-
purpose hot water requirements for use by
individuals, a thermostatically controlled mixing
valve is recommended to reduce the risk of scald
injury. Contact a licensed plumber or the local
plumbing authority for further information.
Keep temperature control of the mixing valve at the
lowest setting which is satisfactory.
When installing a mixing valve, locate it at the
bottom of anti-thermosiphon loop at lea
st 24” high
to prevent excessive hot water from entering mixed
water supply.
VACUUM BREAKER (IF REQUIRED)
Install a vacuum breaker (or vacuum relief valve)
for water heater protection. Prevents siphoning of
the water from the system and collapse of the water
heater.