HTP Hydra Smart RT-199, User Manual, Page: 7 / 73

lp-505 Rev. 000 Rel. 015 Date 1.7.20
7
Contaminant Maximum Allowable Level
Total Hardness
(Commercial Use - Below 140
o
F water
temperature)
200 mg/l
(12 grains/gallon)
Total Hardness
(Commercial Use - Above 140
o
F
water temperature)
120 mg/l
(7 grains/gallon)
Aluminum 0.05 to 0.2 mg/l or PPM
Chloride 100 mg/l or PPM
Copper 1 mg/l or PPM
Iron 0.3 mg/l or PPM
Manganese 0.05 mg/l or PPM
pH 6.5 - 8.5
Sulfate 205 mg/l or PPM
Total Dissolved Solids (TDS) 500 mg/l or PPM
Zinc 5 mg/l or PPM
Dissolved Carbon Dioxide (CO2) 15 mg/l or PPM
Table 1 - Water Quality Specifications
F. Freeze Protection
The water heater control is equipped with freeze protection that
activates based on internal water temperature. See the table below
for details on freeze protection operation.
NOTE: Freeze protection will not be active if the water heater loses
power.
Consider piping and installation when determining heater
location. Damages resulting from incorrect installation or from use
of products not approved by HTP ARE NOT covered by warranty.
NEVER use any toxic chemical, including automotive, standard
glycol antifreeze, or ethylene glycol made for hydronic (non-
potable) systems. These chemicals can attack gaskets and seals
in water systems, are poisonous if consumed, and can cause
personal injury or death.
System Freeze
Protection
(Activates
Based on
Internal Water
Temperature)
Freeze Protection Operation
If control detects water temperature of 41
o
F (5
o
C) and
below, it turns the ceramic heater on to meet a target
temperature of 59
o
F (15
o
C).
Table 2 - Freeze Protection Detail
G. Water Temperature Adjustment and Scalding
This water heater can deliver scalding water. Be careful whenever
using hot water to avoid scalding injury. Certain appliances such as
dishwashers and automatic clothes washers may require increased
water temperatures. By setting the thermostat on this heater
to obtain the increased water temperature required by these
appliances you may create the potential for scald injury.
To protect against injury, install a mixing valve in the water system.
This valve will reduce point of use discharge temperatures by mixing
cold and hot water in branch supply lines. Such valves are available
from your local plumbing supplier.
Table 3 details the relationship of water temperature and time with
regard to scald injury and may be used as a guide in determining the
safest water temperature for your applications.
Approximate Time / Temperature Relationships in Scalds
120 o F More than 5 minutes
125 o F 1 1/2 to 2 minutes
130 o F About 30 seconds
135 o F About 10 seconds
140 o F Less than 5 seconds
145 o F Less than 3 seconds
150 o F About 1 1/2 seconds
155 o F About 1 second
Table 3 - Time and Temperature Relationship in Scalds
Households with small children, disabled, or elderly persons may
require a 120
o
F or lower temperature setting to prevent severe
personal injury or death due to scalding.
An ASSE 1017 or ASSE 1070 temperature limiting or mixing valve is
recommended in installations servicing disabled or elderly persons,
or children. Mixing valves do not eliminate the risk of scalding.
To avoid scalding:
• Set the water heater set point temperature as low as possible.
• Feel water before bathing or showering.
• If thermostatic valves are required, use devices specifically
designed for such purpose. Install these devices in accordance
with instructions provided by the manufacturer.
Failure to install a temperature limiting or mixing valve and follow
these instructions could result in property damage, severe personal
injury, or death due to scalds.
H. High Elevation Installations
Natural gas at high elevation might contain less heating value than
typical 1,000 BTU/cu ft and therefore can cause improper air / gas
mix leading to improper combustion. For natural gas installations
above 3,000 ft, call your gas provider to determine the heating value
of the supplied natural gas.