7
INSTALLATION AND OPERATION INSTRUCTIONS
BT INDIRECT SERIES – WATER HEATERS
2.
Hybrid System
. The space heating zones use zone valves for each zone,
and the water heater is controlled with an additional circulator.
See Section
8.0, Figure 2: Generic Boiler Piping Schematic – Zoned by Circulator.
3.
Zone Valves
. The space heating zones use zone valves for each zone, and
the water heater is controlled with an additional zone valve. Select a valve
with a low pressure drop, and adequate pipe size to assure minimum flow
.
2.4 Priority or Non-Priority for Hot Water
OPTION 1 – PRIORITY
The demand for space heating is interrupted until the hot water demand is
satisfied. This option provides the maximum delivery of hot water. IBC boilers
are easily configured to operate the Hot Water as a priority load. Priority is
recommended when:
1.
The boiler output is less than 100,000 Btu per hour, or
2.
The boiler output required to satisfy the hot water demand is more than 50%
of the boiler output needed to satisfy the space heating demand, or
3.
When an interruption in space heating can be tolerated during long domestic
hot water draws.
The preferred strategy when using Priority is to use a dedicated load circulator
for domestic hot water generation. In most cases the delay in space heating will
not be noticed because of the rapid recovery of the water heater.
OPTION 2 – NON-PRIORITY
The boiler output is divided between space heating and water heating. Heating of
domestic hot water can be reduced during simultaneous space and water heating
demands. The maximum amount of reduction depends on the boiler output,
the number of space heating zones calling, the space heating target water
temperature, and the amount of boiler water flow split between the space heating
and zones and the water heater zone.
2.5 Locating the Water Heater
The water heater should be located in an area where water leakage from the tank
or connections will not result in damage to areas adjacent to the water heater or
to lower floors of the structure. When such a location can not be avoided, a suit-
able drain pan must be installed under the water heater, and the drain pan must
be connected to a drain.
The water heater should be installed as close to the boiler as is practical for easy
access for service. The unit is designed for installation on combustible flooring
and in alcoves, closets, etc.
SURFACE
DISTANCE FROM
COMBUSTIBLES
FOR SERVICE
Front
1"
24"
Rear, Right and Left Sides
1"
1"
Top
1”
1”
Bottom
0"
0”
Table 3: Clearances from heater jacket
WARNING
During operation, the T&P relief
valve may discharge large
amounts of steam and/or hot
water. Therefore, to reduce the
potential for bodily injury and
property damage, a discharge
line MUST be installed that it:
1.
is connected from the valve
outlet with no intervening
valve and directed downward
to a safe point of discharge.
2.
allows complete drainage
of both the valve and the
discharge line.
3.
is independently supported
and securely anchored so
as to avoid applied stress on
the valve.
4.
is as short and straight as
possible.
5.
terminates freely to
atmosphere where any
discharge will be clearly
visible and is at no risk of
freezing.
6.
terminates with a plain end
which is not threaded.
7.
is constructed of a material
suitable for exposure to
temperatures of 375°F or
greater.
8.
is, over its entire length, of a
pipe size equal to or greater
than that of the valve outlet.
DO NOT CAP, PLUG OR
OTHERWISE OBSTRUCT THE
DISCHARGE PIPE OUTLET!
CAUTION
To avoid water damage from leaks,
a drain pan should be installed
under the water heater unless it is
installed in a location where leaks
will not cause property damage.
See Figure 6: Suggested Domestic
Water Piping.
If the discharge from a T&P relief
valve cannot be directed into a
drain or to an area where water
damage will not occur, a drain
pan capable of draining away the
full, continuous discharge flow of
the relief valve should
be installed.
