Application Manual

| Infiniti™ K 160-19914 Application Manual
Data subject to change 10.2018 | Bradford White Water Heaters
4.4 TANK LOADING
Tank loading pairs tankless water heaters with storage tanks to
maximize peak flow for high demand applications. A tank load
system, because of the added storage, can provide a high peak
flow with fewer tankless units and lower installed cost.
Tank loading is recommend for high cycle applications such as
commercial kitchens with hand sprayers.
THESE GUIDELINES SHOULD BE FOLLOWED TO MAXIMIZE
SYSTEM OUTPUT:
• Ensure flow through each water heater is between 3.5-5.0
gpm. See recommended pump models in application section
of this manual.
• For best performance, plumb the system or configure the
tank to draw cold supply water into the water heater during
hot water use.
• Maintain a 20 degree temperature dierence between
tankless set-point and desired tank temperature.
• Do not use a cascading kit in a tank loading application.
• When multiple tankless water heaters are used, the total
equivalent length of piping to each unit should be kept roughly
equal. A reverse return piping scheme is recommended to
equalize flow through each water heater.
• For tank temperature settings above 120°F, the Bradford
White commercial model should be used.
RECIRCULATION LOOP PRESSURE DROP AT 2GPM (FEET OF HEAD)
Table 5 Source: 2009 International Plumbing Code
PRESSURE DROP VS. FLOW
Table 6
EXAMPLE
Sizing a pump for a 4GPM tank loading DHW system with a Infiniti®
K 199 and a 20 ft total loop length.
HEAD LOSS LOOP COMPONENT
22.00 ft
1.00 ft
0.80 ft
+ 0.30 ft
24.1 ft
Infiniti® K 199 (See Fig.2)
20 ft of ¾ copper
8 x ¾” 90 elbows
2 x ¾” Tees (branch)
Minimum Pump Head at 4.0 gpm
Once the loop head loss has been calculated, use the pump
manufacturer’s performance curves to select the proper potable
water circulator at the required flow rate.
# of units
Infiniti™ K 160 Infiniti™ K 199
1 20 feet of head @ 4gpm
21 feet of head @ 4gpm
2 20 feet of head @ 8gpm
21 feet of head @ 8gpm
3 20 feet of head @ 12gpm
21 feet of head @ 12gpm
4 20 feet of head @ 16gpm 21 feet of head @ 16gpm
5 20 feet of head @ 20gpm 21 feet of head @ 20gpm
6 20 feet of head @ 24gpm 21 feet of head @ 24gpm
7 20 feet of head @ 28gpm 21 feet of head @ 28gpm
8 20 feet of head @ 32gpm 21 feet of head @ 32gpm
9 20 feet of head @ 36gpm 21 feet of head @ 36gpm
10 20 feet of head @ 40gpm 21 feet of head @ 40gpm
Material
10 ft Pipe 90˚ Elbow 45˚ Elbow Tee Branch
¾" Type L Copper 0.48
0.1 0.03 0.15
1" Type L Copper 0.14
0.04 0.02 0.07
1.25" Type L Copper 0.06
0.02 0.01 0.04
1.5" Type L Copper 0.03 0.01 <0.01 0.02
2" Type L Copper 0.01 <0.01 <0.01 0.01
| Infiniti® K 160-199 Application Manual
Data subject to change 10.2019 | Bradford White Water Heaters
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