Nature's Comfort NCB-80 Installation And Operating Manual - page 19
Page 19 of 34
L. Filling The Boiler With Water
Once all piping connections are complete, flush about 15 gallons of water into the float stack and
drain, repeating until it comes out clean. Close drain valve and pour Nature’s Comfort boiler
treatment in – required for warranty. Fill the boiler with a hose through the float stack or if you
have installed a fill line, open the valve and allow it to fill, stopping once the float starts to rise. Use
water that is softened and has low iron content if possible for maximum boiler and pump life.
When installing a pump, do not start until boiler is FULL and the impeller and bearings have
been primed!
After filling, remove the top screw on the pump until a steady stream of water flows
and all air has been purged (if applicable). Being a wet-rotor unit, if the pump runs dry at all, it will
seize up as the bearings rely on lubrication from the water.
See maintenance section for full
details on wet rotor pump operation and care.
(pump not included with NCB-80)
During the first heating cycle the water might expand and overflow. This is normal and will occur
anytime too much water has been added. Open the drain valve to keep the float indicator at the
bottom of the rubber cap. Any higher than this and hot water may push the float out and also cause
scalding water to spill out. (Over-fill when boiler is shut off and not in use)
M. Float Level
After priming and starting the circulation pump and bleeding the heat exchanger (see next section),
let the boiler heat up and run for 24 hours then top off the water if needed. The ideal water level is
at the beginning of a heating cycle for the level indicator to be at the bottom of the rubber cap. The
water level will rise and fall during operation as water expands and contracts with temperature
changes. Be sure to keep the boiler full of treated water at all times including through the summer
as this will keep the boiler free from corrosion and when in use, from overheating causing
circulation pump failure.
N. Bleeding the Heat Exchangers
With the pump running (prime and flush bearings first!), simply close a valve on the return side, hold
for 1 second then open quickly. Repeat the procedure four times or until you cannot hear air rushing
through the line.
O. Pre-conditioning Rope Seals
Option 1: (Good) Wet the rope seals with WD-40 before firing the boiler to keep prevent hardening
from smoke and creosote and re-apply 1 or 2 times during the heating season or as needed.
Option 2: (Better) Purchase a tube of high temperature caulk from your dealer or Nature’s Comfort
and lay a bead of caulk on the impression of the door jamb in the rope seals, placing a 2” strip of
wax paper over them. Over-extend the latch open and bounce the door/ash pan closed, then leave
open to fully cure before starting a fire to get a custom seal. Once cured, wet the rope seals with
WD-40 to prevent hardening from smoke and creosote and re-apply 1 or 2 times throughout the
heating season or as needed.
Option 3: (Best but more hassle and messy) Purchase a tube of high temperature caulk from your
dealer or Nature’s Comfort and brush over the entire surface area of the rope seals to permanently
seal out smoke and creosote. Place a 2” strip of wax paper over this. Over-extend the latch open
and bounce the door/ash pan closed, then leave open to fully cure before starting a fire to get a
custom, long term seal.
NOTE! Adjust fuel door if you ever see any amount of smoke. See maintenance section.
Door adjustment is done at the factory but may be required again after installation and before
starting a fire as the seals compress over time. See maintenance section for complete
adjustment and care instructions.