Near Boiler Piping Connections; Circulator Sizing - Lochinvar Knight 151 Installation & Operation Manual

3
Hydronic piping
12. System temperature sensor:
Lochinvar supplies a system temperature sensor.
The sensor is to be installed in the heating loop
downstream from the boiler hot water piping and
heating loop junction.
located far enough downstream to sense system diluted
water temperature.
13. Indirect water heaters:
The outdoor boiler may be piped to an indirect
water heater to heat domestic hot water with the space heat
transfer medium. As depicted on pages 17 through 23
there are two options when utilizing an indirect water
heater.
A. The space heating piping will branch off to flow the
space heat transfer medium through a single wall
heat exchanger coil inside the indirect water heater.
B. The indirect water heater is connected to the system
supply piping.
outdoor boiler's control
water through the indirect water heater. The indirect
water heater's temperature will be regulated by the
outdoor boiler's control.
The outdoor boiler is pre-configured to control the
operation of the DHW pump with Domestic Hot Water
Prioritization programming.
designed to control and balance the space heating
demand by switching between DHW and space heating.

Near boiler piping connections

Figure 3-2A Near Boiler Piping w/Y-Strainer
Y-STRAINER
(RECOMMENDED)
SYSTEM
BOILER
PUMP
PUMP
DRAIN
(TYPICAL)
14
Typically the sensor will be
A pump controlled by the
will regulate the flow of
The DHW programming is
DOMESTIC HOT
WATER PUMP
INDIRECT
DOMESTIC
HOT WATER
TANK
IMG00377
TO FLOOR
DRAIN
Outdoor Knight Boiler Installation & Operation Manual
Lochinvar offers the Squire which is a series of indirect
water heaters. The Squire features a stainless steel vessel
with a single wall stainless steel heat exchanger.
It is up to the installer to ensure the
CAUTION
minimum system flow is not less than the
minimum boiler flow at any time.
WARNING The National Standard Plumbing Code
and the Uniform Plumbing Code limit the
pressure of the heat transfer fluid to less
than the minimum working pressure of the
potable water system up to 30 psi maximum.
Also, the heat transfer fluid must be water
or other non-toxic fluid having a toxicity of
Class 1, as listed in Clinical Toxicology of
Commercial Products, 5
14. Y-Strainer:
Field supplied. A Y-strainer or equivalent multipurpose
strainer is recommended at the inlet of the heat exchanger
to remove system particles from older hydronic systems and
protect newer systems.

Circulator sizing

The outdoor boiler heat exchanger does have a pressure drop,
which must be considered in your system design. Refer to the
graph in FIG. 3-3 for pressure drop through the outdoor boiler
heat exchanger.
Figure 3-2B Near Boiler Piping w/Low Loss Header
SYSTEM SENSOR
AIR VENT VALVE
AIR SEPARATOR
LOW LOSS HEADER
(TYPICAL)
Y-STRAINER
(RECOMMENDED)
BOLIER PUMP
th Edition.
FILL VALVE
DRAIN
(TYPICAL)
EXPANSION TANK
DRAIN VALVE
INDIRECT
DOMESTIC
HOT WATER
IMG00378
TO FLOOR
DRAIN