Lochinvar 000 through 2 - Manual (Page 70)

70
DOMESTIC
HOT WATER
SUPPLY BOILER
This section applies only to those appliance used to supply
domestic hot water, installed with a storage tank(s). The integral
circulating pump installed in the bypass piping assembly is used
to control water ve loc i ty through the appliance. Proper water
velocity is important for correct operation of your water heater or
hot water supply boiler.
WATER HEATERS
1,500,000 - 2,000,000 Btu/hr Models
DOMESTIC HOT WATER SUPPLY BOILERS
1,500,000 - 2,000,000 Btu/hr Models
DRAIN
LOCK-TEMP
STORAGE TANK
RELIEF VALVE
TO DRAIN
BUILDING
HOT WATER SUPPLY
MIXING
VALVE
COLD WATER SUPPLY
BUILDING RETURN
FIG. 83 Typical Water Heater Piping with Storage Tank
This section contains specific in struc tions for those appliances
used to supply domestic hot water. All warn ings, cautions, notes
and instructions in the general installation and service sections
apply to these instructions. Hot water supply boilers and water
heaters are designed for installation with a storage tank. The
operation of the integral circulating pump, properly sizing of the
piping between the tank and heater and the control of water
velocity, as explained below, are im por tant for correct operation
of your water heater or hot water supply boiler.
WATER VELOCITY CONTROL
To ensure proper velocity through the heat exchangers, it
is nec es sary to regulate the temperature rise across the
heat exchanger from inlet to outlet. This must be done on
initial installation and periodically re checked. With the
correct temperature rise across the heat exchangers when
the water heater is firing at 100% of rated input, you may
be assured of the proper velocity in the tubes. This will
yield long life and economical operation from your water
heater or hot water supply boiler.
IMPORTANT
Excessive lime/scale build-up in the heat exchanger tubes is a
result of restricted flow and too little velocity in the tubes.
Excessive pitting or erosion in the tube is caused by high water
flow and too much velocity through the tubes. Care should be
taken to measure temperature rise and maintain a velocity as
follows:
BYPASS - Initial Set-up of Maximum Water Flow
On initial start-up of the Intelli-Fin the maximum water flow
through the two in ter nal heat exchangers must be manually set
before the automatic operation of the bypass begins.
CAUTION
ƽ
The maximum flow rate through an Intelli-Fin water heater
with a copper heat exchanger must be set to provide and not
exceed 90 GPM.