Crown Boiler FSZ080, Руководство по установке

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IMPOrtant
•
Some indirect water heaters may not be suitable for use with a steam boiler. Consult the water heater
manufacturer’s guidelines before installing it in this type of system.
•
Boiler water temperatures and flow rates in this type of system may be considerably lower than those upon which the
water heater manufacturer’s ratings are based. This may result in substantially longer water heater recovery times.
2) Flow Restrictor (Recommended) - If water is drawn from the tankless coil at a rate in excess of the rating in Table 2.3, the
temperature of the hot water may be too low to be of use. The use of a flow restrictor will prevent this problem by limiting the
rate at which water can pass through the tankless heater. If a restrictor is used, select one having a rating in GPM approximately
equal to the rating shown in Table 2.3. If possible, locate this restrictor at least 3 feet from the tankless heater inlet so that it is
not subjected to excessive temperatures when no water is flowing through the coil.
3) Pressure Relief Valve (Required) - Limits the pressure in the tankless heater and piping. Use an ASME constructed valve
designed for domestic water service, such as the Watts #3L. Note that this is a pressure relief valve, not a T&P valve. Select a
valve with a pressure setting less than or equal to the working pressure marked on the tankless coil. Pipe the discharge to a safe
location using piping the same size as the discharge connection on the valve.
4) Hose Bib Valves (Recommended) - These valves permit the coil to be periodically “backflushed” to remove sediment.
5) Globe or Ball Valve (Recommended) - Used to adjust the flow through the entire tankless heater system if needed.
tanKlESS HEatEr PIPInG
FSZ Series boilers equipped with tankless heaters are supplied with a Honeywell L4006A limit control and a 1/2” NPT well.
These components are shipped unmounted. This control is mounted in the 1/2” tapping “R” in the center of the tankless coil.
Make the piping connections to the coil before installing the L4006A, making sure that these connections are routed so that
they will not interfere with the L4006A.
Pipe the heater as shown in Figure 9.2. The components in this system and their functions are as follows:
1) Mixing Valve (Required) - During the heating season, the water exiting the tankless heater may be 180 degrees or more.
The mixing valve blends hot water leaving the tankless heater with cold water so as to maintain the hot water supplied to the
fixtures at a fixed temperature. This saves energy, increases the amount of usable hot water available to the homeowner, and
reduces the risk of scalding.
Install a mixing valve with a setting range of approximately 110 to 130F. Follow the manufacturer’s instructions for
installing this valve. Usually a “heat trap” will be required between the coil and the “hot” connection on the mixing valve.
WARNING
A mixing valve does not eliminate the risk of scalding.
• Set the mixing valve and boiler low limit adjustments as low as possible.
• Feel water before showering or bathing.
• If anti-scald or anti-chill protection is required, use devices specifically designed
for such service. Install and maintain these devices in accordance with the
manufacturer’s instructions. Do not use the mixing valve as a substitute for
pressure balancing valves or other devices required by plumbing codes to protect
against scalding.