Kenmore 5EW1.75 - Manual (Page 14)

7, Boilers may be factory packaeed with a tankless heater coil see figure below. This coil provides
instantaneous heating of water for domestic use - if proper burner and water supply line controls are used.
Tankless coils are meant to provide domestic hot water for intermittent draws, not continuous flow.
IMPORTANT
Do not use a tankless coil if your water is excessively hard with
lime or other deposits which will accumulate inside the coil.
When using a tankless coil, the boiler has been configured so the Honeywell L8124C Combination
Hi/Low Limit Aquastat Relay mounts on a thermowell (provided) which needs to be installed in the 3/4”
tapping on the tankless coil. By mounting the aquastat on the coil, the tankless coil performance is
maximized by making the burner respond more quickly to a call for domestic hot water. A tempering
valve (mixing valve) is also recommended as shown in figure below. A flow restrictor may be required
on the tankless coil inlet piping so that flow rates are matched to boiler heat input (see table below).
Boiler Burner Firing Input Tankless
Model Rate (gph) (MBH) Rating (gpm)t
3EW.65T 0.65 91 2.90
3EW.75T 0.75 105 3.00
3EW1.00T 1.00 140 3.25
4EW.90T 0.90 126 3.15
4EW1.25T 1.25 175 3.50
4EW1.50T 1.50 210 3.75
5EW1.20T 1.20 168 3.45
5EW1.75T 1.75 245 4.00
5EW2.00T 2.00 280 4.25
Gallons of water per minute heated from 40°F to I40°F with
200°F boiler water temperature, intermittent draw
UNTEUrtnCO HOT WATEJt
( « „«««M ..M HOT WATEH
TANKLESS COIL
CENTER LINE
or COLO TAP
r 10 ir
n—
TEMPEfHNC
valve
COLO water «NLtr
SHUT-Orr
VALVE
ty
u
ft' NPT
NPT '
CONTROL WELL
12