Boiler Flow Rates; Placing In Operation - Lochinvar CHF2 Installation And Service Manual

MAXIMUM REQUIRED FLOW
FOR HEATING BOILER
CAUTION !!
The maximum flow rate through the boiler
with a copper heat exchanger must not exceed
the following:
Input-Btu/hr
300,000
990,000 - 2,070,000
If higher flow rates are required through the boiler,
a n o p t i o n a l C u p r o - N i c ke l h e a t ex c h a n g e r i s
ava i l a bl e . C o n s u l t t h e f a c t o r y f o r s p e c i f i c
application requirements.
The heat exchanger is generally capable of operating
within the design flow rates of the building heating
system. Should the flow rate exceed the maximum
allowable flow rate through the boiler an external
bypass must be installed. The bypass should be fully
sized with a balancing valve to allow for proper
adjustment of flow. Flow rate can be determined
by measuring the temperature rise through the
boiler.
BOILER BYPASS REQUIREMENTS
Boiler Bypass Piping
MAKE-UP
WATER
PRV
TO
SYSTEM
SYSTEM
PUMP
AIR
SEPARATOR
BY-PASS
VALVE
Maximum Flow
60 GPM
90 GPM
EXPANSION TANK
LWCO
(OPTIONAL)
FROM
FIG. 54
SYSTEM
The installer must insure that the boiler is supplied
with adequate flow without excessive temperature
rise. It is recommended that this boiler be installed
w i t h a by p a s s i n t h e p i p i n g i f t h e m a x i m u m
recommended flow rate is exceeded. The bypass
will help to insure that the boiler can be supplied
with adequate water flow. Flow rates exceeding the
maximum recommended flow will result in erosion
of the boiler tubes. A typical bypass with a valve
is shown in FIG. 54 will allow control of boiler flow.
TEMPERATURE/PRESSURE
This boiler is equipped with a dial type temperature/
pressure gauge. This gauge is factory installed in
the outlet side of the heat exchanger. The gauge
has one scale to read system pressure and a separate
s c a l e t o r e a d wa t e r t e m p e r a t u r e i n ° F.
t e m p e r a t u r e / p r e s s u r e g a u g e c a n b e u s e d t o
determine temperature rise by f irst recording the
temperature of the boiler water with the boiler off.
Record the temperature of the boiler water as the
boiler fires and the discharge temperature stabilizes.
Subtract the boiler water temperature with the boiler
off from the stable outlet water temperature with
the boiler f iring. This temperature difference is the
temperature rise.
TYPICAL HEATING
BOILER INSTALLATIONS
General Plumbing Rules
1. Check all local codes.
2. For ser viceability of boiler, always install
unions.
3. Always pipe pressure relief valve to an open
drain.
4. Locate system air vents at highest point of
system.
5. Expansion tank must be installed near the
boiler and on the suction side of the pump.
6. Support all water piping.
PLACING THE BOILER
IN OPERATION
Filling the System: All air must be purged from the
system for proper operation. An air scoop and air
vent must be located close to the boiler outlet and
there should be a minimum distance between the
cold water feed and the system purge valve.
48
GAUGE
T h e