Table of Contents
Advertisement
WATER CONNECTIONS AND PIPE SIZE
Inlet and Outlet Connections
The inlet and outlet water connections to the unit are cupronickel and connect directly to the copper heat exchanger.
Use proper soldering/brazing attachment practices to make system and building connections. Twisting or bending
loads on these connections may cause damage to the heat exchanger and are not covered by warranty. For ease of
service, install unions on inlet and outlet of the unit. The connection to the unit marked "Inlet" on the header connects
to the return from the system (water to be heated). The connection on the header marked "Outlet" connects to the
supply side of the system (hot water out of the unit).
Copper piping connecting the PRIMERA
(water heater) or main building heating loop (boiler) must be at least 2" diameter for models 399, 750, 1200 and 1600
and must be at least 2-1/2" diameter for models 1000 and 2000. (Note: 2" cupronickel or brass pipe and fittings may be
used instead of 2-12" copper for models 1000 and 2000).
To facilitate connection of 2-1/2" copper pipe to the 2" cupronickel inlet and outlet connections, a quantity of two 2" x
2-1/2" increaser couplings are attached by a tie strap to the upper cupronickel outlet connection near the relief valve. If
the circulator pump outlet is directly connected to the cupronickel inlet, the 2" x 2-1/2" increaser can be used as part of
the connection of 2-1/2" copper pipe to the circulator pump inlet. If the pump is mounted remote from the cupronickel
®
PRIMERA
inlet, the increase from the 2" pump inlet and outlet must be made with brass or bronze fittings before
connecting to the 2-1/2" copper pipe.
Improper use of smaller copper pipe sizes will cause increased back pressure and excessive water velocity. Increased
water back pressure can cause the circulator pump to provide inadequate flow to maintain successful operation of the
®
PRIMERA
and excessive water velocity can cause pipe erosion which can lead to piping failure.
®
For PRIMERA
heating boilers, black steel pipe (never use galvanize pipe or fittings) can be used instead of copper.
COMMON MINIMUM WATER MANIFOLD SIZE FOR MULTIPLE UNITS (USING TYPE-L COPPER)
Pipe sizing chart provides minimum pipe size for common manifold piping to insure adequate flow.
Number
399,000 btuh
of Units
540,000 btuh
1
2"
2
2"
3
2½"
4
3"
5
3½"
6
3½"
®
* PRIMERA
boiler models 1000B and 2000B connections between the PRIMERA
connections, the circulating pump and the main building heating loop can be made with 2" pipe if steel piping is used.
For other models and for multiple units, follow the manifold sizing in the chart.
MAINTAINING PROPER FLOW RATE / TEMPERATURE RISE
Important - To insure proper velocity through the heat exchanger, it is necessary to regulate the temperature rise
across the heat exchanger from inlet to outlet. This must be done on initial installation and periodically rechecked. With
the correct temperature rise across the heat exchanger, you may be assured of the proper velocity in the tubes. This
will yield long life and economical operation from your appliance. Excessive lime build-up in the tubes is a result of too
little velocity in the tubes. Too much velocity through the tubes or pipes causes excessive pitting or erosion in the
tubes or pipes. Care should be taken to measure temperature rise and maintain a velocity as follows:
1.
With the pump running and the PRIMERA
should read the same temperatures. If they do not, an adjustment must be made to your final calculation.
2.
Turn the PRIMERA
temperature to stabilize (about 5 to 10 seconds). Viewing both temperatures as quickly as possible, record the
difference between the inlet and outlet temperatures. This difference is the "temperature rise."
3.
Compare this recorded temperature rise with the values shown in the "Required Temperature Rise" table below.
Should adjustment be needed, proceed as follows:
®
cupronickel inlet and outlet to the circulating pump and the storage tank
750,000 btuh
1,000,000 btuh
2"
3"
3½"
4"
5"
5"
®
®
boiler or water heater full on (firing at maximum input) and allow a brief time for the outlet
1,200,000 btuh
2½" (*)
3½"
2½"
4"
3½"
5"
5"
6"
boiler or water heater off (not firing), the inlet and outlet thermometers
11
1,6000,000 btuh
2"
2"
3"
3½"
4"
4"
5"
5"
5"
5"
®
cupronickel inlet and outlet
2,000,000 btuh
2½" (*)
3½"
4"
5"
5"
6"
34-50 04/02/2010
Hide quick links:
Advertisement
Table of Contents
