BTH Electric Boilers
USE & CARE MANUAL
(Revision August /06)
, Page
8.
Water pressure makeup regulator
Make-up systems
must be employed
as required
by codes. An a
utomatic fill valve
must be used
with a backflow preventer as required, to maintain
minimum system pressure by supplying water to
make up for leakage.
Air bleeder
Oxygen should be excluded from the system to
prevent corrosion. As mentioned in the expansion
tank paragraph above, this precludes the use of
air in direct contact with the boiler water as a
pressurization means.
Installation of manual or automatic air vent
devices prevents air from accumulating in the
system. Air vents should be installed at all high
points to remove trapped air during initial setup
and to ensure that the system is tight. Regularly
purge the air out of the system while taking care to
avoid personal injuries or property damage
caused by hot boiler water spray.
Circulator zoning recommendations
The preferred location of the circulator pump for
each zone is on the boiler supply side, with the
expansion tank between the boiler and the pump.
A flow check valve must be installed in each zone,
preferably on the outlet side of each circulator
pump, to prevent water flow to other zones where
no heat is required.
Zone valve zoning recommendations
The preferred location of the circulator pump is on
the boiler supply side, with the expansion tank
between the boiler and the circulator. Use zone
valves with low pressure drop.
Dual energy installation
In order to obtain a special rate from your electric
utility for residential use, your BTH boiler can be
hooked-up to an existing oil heater. Contact your
electric utility to find out if your property is eligible
for such rates and how to register for them.
The CBE-EM dual-energy control (an available
option, three-way, motorized valve (1’’ NPT F
standard) included) is specially designed to
electric utility standards. The CBE-EM control
selects the least expensive energy source based
on outside temperature, user choice or a signal
from your utility.
The CBE-EM dual-energy control will start up the
oil burner upon receiving the appropriate signal,
even if the thermostat in the house is not calling
for heat. It will shut off when the temperature in
the boiler reaches its target on the Limit Control. It
is for this reason that the piping requires an anti-
gravity valve (flow check valve) or motorized zone
valves.
A three-way, motorized valve (1’’ NPT F standard)
will direct the water flow either to the oil-fired
heater or to your DTH electric boiler, depending
on the signal received. This way, your oil heater
will cool down and eliminate any energy loss,
either through the chimney or by way of
conduction in the boiler room.
