Ultra Boiler Manual

Part number 550-100-440/0122
56
  

e closest circulator selection (from Figure55,page57)
that can deliver 12gpm at 22.7feet head is either a Taco
1400 (top chart) or a Taco0013 (bottom chart).
Note that, if the water heater were piped as in Figure53,
then H1 would be 0, so total head loss would be H2 + H3,
or 9.4 feet (3.9 + 5.5). A Taco 0010 would handle the load
if piped this way.
See previous pages in this manual for piping details
not shown below. For DHW piping as shown below,
use sizing information in Figure54,page57.
Figure 52 DHW piping direct-connected across the boiler
Figure 53 DHW piping as a secondary circuit — for high-ow-rate
applications

For Weil-McLain AQUA PLUS water heaters,
refer to the AQUA PLUS water heater manual for
application information. Also see quick-select in-
formation on page14. e information here is for
other water heater designs.
When using the Ultra boiler for dedicated DHW ap-
plications, use the circulator supplied with the boiler
(007 for Ultra-80/105; 0014 for Ultra-155/230/299;
0013 for Ultra-399) to circulate to the water heater,
except where higher ow rates may be required for
the heater used. Use the following method to select
a circulator for the water heater on combined space
heating/DHW systems.
1. To pipe the DHW tank and boiler, follow the suggested piping
diagrams beginning on page12.
2. Figure55,page57 shows the pump curves for typical DHW
circulators. Use these curves along with boiler pressure drop
data from Figure54, page57 to size the DHW piping and
circulator.
3. Procedure to select a DHW circulator:
Step 1:
From the water heater manufacturer’s data, nd:
• Required boiler water ow rate, GPM, at 190°F.
• Pressure drop across the water heater at this ow rate, in
feet water column (this is H3 in the formula below).
Step 2:
Find your boiler model in Figure54,page57.
Select a ow rate in the Flow rate column just larger than the
required boiler water ow rate from Step1.
Step 3:
Read across the row selected to nd the boiler pressure drop,
H1, and the pressure drop in the piping, H2. Make sure to
use the copper pipe size given in column 3 when piping the
water heater.
Step 4:
Add the pressure drop across the water heater, from Step 1,
to the values of H1 and H2 for total head loss.
H
total
= H1 + H2 + H3
Step 5:
Select a circulator that can deliver the required ow rate,
gpm, against the total head loss found in Step 4.
Example:
Consider an Ultra-155 used with a water heater that requires
a ow of 12 gpm with boiler water at 190°F. e water heater
is to be piped as in Figure52.
From the example water heater manufacturer’s data, the
head loss across the water heater at 12 gpm is 5.5 feet water
column.
Read down the rst column of Figure54,page57 for the
Ultra-155 until you nd a ow rate just larger than the re-
quired 12 gpm. You’ll nd a value of 13 gpm in the third row.
At 13 gpm, with an Ultra-155, the recommended pipe size
is 1¼inch. From the table, the head losses are:
H1 = 13.3 feet H2 = 3.9 feet
H3 = 5.5 feet (from water heater manufacturer’s data)
H
total
= 13.3 + 3.9 + 5.5 = 22.7 feet.