Pump Requirements; Temperature Adjustment; Heat Exchanger - Lochinvar 45,000—500,000 Btu/hr Models Installation And Service Manual

The standard pump selection is based on the following
pipe and fittings from the unit to the storage tank:
6 - 90° elbows
2 - unions
Plus the following length of straight pipe based on the
heater size:
90,000 thru 360,000 Btu/hr Models
Not more than 45 feet of straight pipe
399,000 thru 500,000 Btu/hr Models
Not more than 25 feet of straight pipe
For every elbow and tee in excess of those shown above,
DEDUCT 5 FEET from maximum allowable straight
pipe in heater to tank circulating loop.
MINIMUM PUMP PERFORMANCE
Based on heating potable water with a hardness of 5 to
25 grains per gallon and total dissolved solids not
exceeding 350 ppm. See "Water Chemistry."
BTU INPUT
90,000 - 500,000

HEAT EXCHANGER

This is a highly sophisticated heat exchanger, designed
to carry water in such a way that it generates a scouring
action which keeps all interior surfaces free from
build-up of impurities.
design of the tubes sends water into the headers at a
properly rated velocity.
headers, in turn, creates a high degree of turbulence
which is sufficient to keep all contaminants in
suspension. This "scouring action" provides greater
cost savings for owners. Tubes are always able to
transfer heat at peak efficiency. Every surface within
this water containing section is of a nonferrous material,
providing clear, clean, rust-free hot water.
copper tubes-finned on the outside for maximum heat
transfer-glass lined cast iron one piece cored headers
make up an entirely rustproof unit. On all models,
header inspection plugs can be removed for field
inspection and cleaning of copper tubes. The entire heat
exchanger may be easily removed from the unit.
2 - ball valves
1 - cold water tee
GPM Ft. Hd.
30 8
The straight-line, two pass
The configuration of the
Straight
THERMOSTAT SETTINGS
1. The thermostat is adjusted to a low test setting
when shipped from the factory.
2. Set the thermostat to the lowest settings which will
satisfy hot water demands and prevent risk of scald
injury.

TEMPERATURE ADJUSTMENT

(Domestic Hot Water Use)
This unit has an adjustable thermostat to control water
temperature. See temperature adjustment procedure in
the general section of the manual. The thermostat is
factory preset at approximately 125°F. Households with
small children or invalids may require 120°F or lower
temperature setting to reduce risk of scald injury. Some
states may require a lower temperature setting. Check
with your gas supplier for local requirements governing
the temperature setting. Remember, no water heating
system will provide exact temperature at all times.
Allow a few days of operation at this setting to
determine the correct temperature setting consistent
with your needs.
NOTE:
(1) This water heater, when set at the lower
temperature setting, is not capable of producing
hot water of sufficient temperature for sanitizing
purposes. (2) Higher stored water temperature
increases the ability of the water heater to supply
desired quantities of hot water, however
remember:
CAUTION:
Hotter water increases the risk of scald injury.
Incorrect piping of the cold water supply to the system
may result in excessive low temperature operation
causing condensate formation on the heat exchanger
and operational problems. The cold water supply piping
must be installed in the discharge piping from the heater
to the storage tank. This allows the cold water to be
tempered in the storage tank before entering the heater.
See typical installation drawings provided with the unit
for correct piping. Higher water temperatures reduce
condensate formation.
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