Crown Boiler TWB Series, Руководство по установке

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If this boiler is installed with an optional tankless heater, pipe the heater as shown in Figure 9.1. The components in this
system and their functions are as follows:
1) ASSE 1070 or ASSE 1017 Listed Tempering Valve (Required) - Like all tankless heater equipped boilers, the control
provided with this boiler is not designed to regulate the domestic water temperature exiting the tankless heater. A
tempering valve is therefore required for domestic water temperature control. Select and install this valve in accordance
with the valve manufacturer’s instructions and applicable codes. Note that some codes require additional tempering
devices at some of the fixtures as well.
2) Flow Restrictor (Recommended) - If water is drawn from the tankless coil at a rate in excess of the rating in Table 2.2,
the temperature of the hot water may be too low to be of use. The use of a flow restrictor will help 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 2.2. 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) DHW 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 or #53L. 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 tankless heater to be periodically “backflushed” to remove
sediment.
5) Globe or Ball Valve (Recommended) - Used to aid in back flushing the tankless heater and to isolate the DHW piping if it
must be serviced. In addition, the upstream valve may be used to limit the DHW flow if necessary.
6) Unions (Required) - Tankless heaters may require periodic gasket replacement or other maintenance which requires
removal of the heater from the boiler. Install unions anywhere in the tankless heater piping that will facilitate removal of
the heater.
IX Tankless Heater Piping
DANGER-SCALD HAZARD
The control supplied with this boiler is not intended to provide accurate control of the
domestic water temperature leaving the tankless heater. An installer supplied, ASSE 1017
or ASSE 1070 certified tempering valve is therefore REQUIRED as part of this boiler’s
installation.
• Select, and install tempering valve in accordance with the valve manufacturer’s
instructions and applicable local codes. In the absence of such codes follow the
Uniform Plumbing Code (IAPMO/UPC-1). Also note that additional tempering valves
may be required at the fixtures themselves.
• Adjust low limit and tempering valve to the lowest practical setting.
• Feel water before showering or bathing.