Follow manufacturer’s installation instructions.
EXPANSION TANK
(1)
:
Locate on suction side of pump
(where it will protect all modules under all operating
conditions). Follow manufacturer’s instructions.
MANUAL RESET HI-LIMIT
(1)
:
Locate in supply piping
downstream of connection of the last module.
LOW WATER CUTOFF
(1)
:
(Electronic type or float
type) Locate in supply header. Follow manufacturer’s
installation instructions. If heating plant is to be
installed above level of radiation, a low water cutoff
must be installed to protect plant from dry fire.
CAUTION: To prevent accidental dry fire, do not
install isolation valves between low water cutoff
and the module.
CAUTION: Do not install any low water cutoff in a
location where water will not freely drain away from
the float or probe (i.e., in a pipe tree or loop) should
a low water condition develop in the module.
For electronic probes, vertical installation (where all
water can freely drain away from probe) is preferred
over horizontal. Do not install in small diameter pipe
nipples or bushings, as insufficient clearance to probe
may result in corrosion and/or erroneous readings.
SYSTEM PUMP
(1)
Locate in the heating plant supply
piping, downstream of the modules. Follow manufac-
turer's installation instructions.
NOTE: Heating plants must not be used without
forced system circulation, as overheating/failure of
cast iron sections may result.
MOTORIZED VALVE:
Commonly used on combination
space/volume water heating systems to ensure a pri-
ority for domestic hot water over space heating. (2"
globe valve with motor for MC2 heat exchanger) (2-
1/2" butterfly valve with motor and linkage for MC-3
heat exchangers) See Figure 3.5 for location. Follow
manufacturer’s instructions.
FLOW CHECK VALVE (Optional):
Important to con-
trol direction of flow and prevent gravity circulation.
Locate where it cannot cause isolation of any particu-
lar loop or zone from the main system. Follow manu-
facturer’s installation instructions.
FLOW METER (Optional):
Will help determine total
system water volume for purposes of system water
treatment, as well as aid in identification of a system
leak. Follow manufacturer’s installation instructions.
STRAINER (Optional):
For retrofit or steam conver-
sion systems, basket-type strainer will trap loose sys-
tem scale. Locate in return water line. Follow manufac-
turer’s installation instructions.
BACKFLOW PREVENTER (Optional):
Used as a
means of isolation (space heating system from main
water supply) to safeguard against potential hazard of
fill valve connection allowing migration of water treat-
ment chemicals into potable water supply. Follow man-
ufacturer’s installation instructions.
OTHER COMPONENTS:
Install all other waterside
components such as shut-off valves, mixing valves,
thermometers and supply water temperature sensors;
install sensors or probes in a location that will sense
supply water temperature from all modules. Follow
manufacturer's installation instructions.
STEP 4: HYDRONIC COMPONENTS (CONTINUED)
(1)
For heating plants providing volume water heating only (instantaneous recovery or with storage tank), see Figures 3.6
and 3.7 on page 10 for installation guidelines.
8
STEP 5: HYDROTESTING THE SYSTEM
It is recommended that hydrotesting of the entire heat-
ing system be performed before installing jackets and
controls or wiring the system. Fill the entire system
with water and pressurize. All fittings and components
should then be inspected for visible signs of leakage. If
no pressure drop is detected for a two-hour period
under pressure, the heating system may be considered
water tight.
