Warning
During operation, the temperature and pressure relief valve may discharge large amounts of
steam and/or hot water. To reduce the potential for bodily injury and property damage, a
discharge line
must
be installed that:
Is connected from the valve outlet with no intervening valve, and directed downward to
a safe point of discharge.
Allows complete drainage of both the valve and the discharge line.
Is independently supported and securely anchored to avoid applied stress on the valve.
Is as short and straight as possible.
Terminates freely to atmosphere where any discharge is clearly visible and at no risk of
freezing.
Terminates with a plain end, which is not threaded.
Is constructed of a material suitable for exposure to temperatures of 375°F or greater.
Is, over its entire length, of a pipe size equal to or greater than that of the valve outlet.
! Do not cap, plug, or obstruct the discharge pipe outlet.
2.3 Priority or non-priority for hot water
2.3.1 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. You can easily configure IBC boilers to operate the hot water
demand 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 when
3. An interruption in space heating can be tolerated during long domestic hot water draws.
When using the Priority option, the preferred strategy 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.
2.3.2 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:
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2.3 Priority or non-priority for hot water
Summary of Contents for INTERSTAR IWT Series
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