6
System piping
(continued)
Water Heater Pump Applications
Model
*Pipe Size Armstrong
Flow Rate
(GPM)
Loss
(FT/HD)
Temperature
Rise
150
1-1/4"
E8
16
16.6
18°F
199
1-1/4"
E8
21
11.8
18°F
285
2"
E17
30
17.1
18°F
399
2"
E24
39
21
18°F
500
2"
E24
52
18.2
18°F
Installation & Operation Manual
29
Table 6C
Water Heater Pump Applications / Recommended
Temperature Rise
Piping components
Water heater system piping:
Water heater system piping MUST be sized per the pipe
requirements listed in Table 6C. Reducing the pipe size can
restrict the flow rate through the water heater, causing
inadvertent high limit shutdowns and poor system performance.
Check valves:
Field supplied. Check valves are recommended for installation
as shown in FIG.’s 6-4 thru 6-8.
Water heater isolation valves:
Field supplied. Full port ball valves are required. Failure to use
full port ball valves could result in a restricted flow rate through
the water heater.
Anti-scald mixing valve:
Field supplied. An anti-scald mixing valve is recommended
when storing domestic hot water above 115°F.
Unions:
Field supplied. Recommended for unit serviceability.
Temperature and pressure relief valve:
Factory supplied on water heaters. The temperature and
pressure relief valve is sized to ASME specifications. Storage
tanks may require additional valves depending on local codes.
Tank sensor:
Lochinvar supplies a tank sensor. The tank sensor must be
installed in the tapping provided in the lower 25% of the storage
tank to achieve proper operation. As shipped from the factory,
the tank sensor is in the literature package shipped with the unit.
Placing the sensor in the tapping provided on the storage tank
will improve temperature response and prevent short cycles of
operation.
Pump sizing and flow requirements are based on 45 feet of
piping, 4 - 90° elbows, and 2 - fully ported ball valves.
NOTICE
Water chemistry
NOTICE
Water temperature rise and
maximum flow data is based on
heating potable water with a hardness
of 5 to 25 grains per gallon and total
dissolved solids not exceeding 350
ppm.
The required temperature rise and the standard
circulating pump are sized based on the heating of
potable water with a hardness of 5 to 25 grains per gallon
and a total dissolved solids not exceeding 350 ppm.
Consult the manufacturer when heating potable water
exceeding these specifications.
Scalding
This water heater can deliver scalding temperature water at any
faucet in the system. Be careful whenever using hot water to
avoid scalding injury. Certain appliances such as dishwashers
and automatic clothes washers may require increased
temperature water. By setting the thermostat on this water
heater to obtain the increased temperature water required by
these appliances, you may create the potential for scald injury.
To protect against injury, you should install a mixing valve in the
water system. This valve will reduce point of discharge
temperature by mixing cold and hot water in branch supply
lines. Such valves are available from the local plumbing supplier.
Figure 6-3
Scald Warning Label Located on the Appliance
Heating of high hardness and/or high total dissolved solids water
may require a larger circulating pump, and a revised
temperature rise specification based on the water chemistry of
the water to be heated.
Water with a hardness of less than 5 grains per gallon will usually
have a pH which can be aggressive and corrosive causing non-
warrantable damage to the pump, and associated piping.
Corrosion due to water chemistry generally shows up first in the
hot water system because heated water increases the rate of
corrosive chemical reactions.
The following chart (Table 6B) 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°F
More than 5 minutes
125°F
1 1/2 to 2 minutes
130°F
About 30 seconds
135°F
About 10 seconds
140°F
Less than 5 seconds
145°F
Less than 3 seconds
150°F
About 1 1/2 seconds
155°F
About 1 second
Table 6B
Approximate Time / Temperature Scald Chart
