13
7. Boilers may be factory packaged with a
tankless heater coil see gure 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 ow.
sYsTeM pipiNg arraNgeMeNT alTerNaTe Near BOiler pipiNg
IMPORTANT! Do not use a tankless coil if your
water is excessively hard with lime or other de-
posits which will accumulate inside the coil.
When using a tankless coil, the boiler has been
congured so the Honeywell L8124C Combina-
tion Hi/Low Limit Aquastat Relay mounts on a
thermowell (provided) which needs to be installed
in the ¾” tapping on the tankless coil. By mount-
ing the aquastat on the coil, the tankless coil
performance is maximized by making the burner
Boiler
Model
Burner
Firing
Rate (gph)
Input
(MBH)
Tank less
Rating
(gpm)‡
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 140°F with
200°F boiler water temperature, intermittent draw
respond more quickly to a call for domestic hot
water. A tempering valve (mixing valve) is also
recommended as shown in gure below. A ow
restrictor may be required on the tankless coil inlet
piping so that ow rates are matched to boiler heat
input (see table below).
To Next Page
Loading...
