Installation & Service Manual
4Water connections (continued)
PUMP INSTALLATION AND MAINTENANCE: The boiler circulating pump must be purchased locally. For installation and maintenance information on the circulator pump, refer to the pump manufacturers instruction package included with the pump.
Circulator Pump Specifications
1.Maximum operating pressure for the pump must exceed system operating pressure.
2.Maximum water temperature should not exceed nameplate rating.
3.Cast iron circulators may be used for closed loop systems.
4.A properly sized expansion tank must be installed near the boiler and located on the suction side of the pump.
Circulator Pump Operation
Boilers are equipped with a relay for controlling the circulation pump for the hot water loop. The relay turns ON and OFF in response to the “W” input from the wall thermostat or zone control.
The field installed boiler pump MUST NOT exceed 1 h.p. For continuous pump operation, wire the system pump to the 120V supply. The pump should be connected at the
PERFORMANCE LOOP
These units are equipped with an integral performance loop, which is designed to provide efficiency optimization by maintaining a constant flow through the unit’s heat exchanger loop when building system flow is reduced. The performance loop assembly is standard equipment and is NOT to be used as a system or boiler pump.
NOTICE | The performance loop is dedicated to | |
the unit and does not affect the | ||
| ||
| ||
| building’s system or primary/secondary | |
| flow characteristics and will not | |
| circulate the building. |
It is acceptable to remove the performance loop as long as the following requirements are met:
1.The boiler is piped to the system in primary/secondary fashion.
2.The system setpoint is 140°F or higher.
3.The boiler circulating pump is sized for the appropriate flow through the boiler.
4.The system sensor is installed in an acceptable location for sensing the system supply temperature.
5.If water temperature is below 140°F a low temperature bypass must be installed, (VAL30000 - 1 1/2" LTV Valve Kit) and follow the piping diagram in FIG.
junction box as shown in FIG.
120V
SUPPLY
NOTICE
WARNING
If removal of the performance loop is necessary, consult the manufacturer for a Solution Without a Performance Loop (KIT30068).
Failure to install the system sensor can cause operation problems such as nuisance high limit trips.
TO
UNIT
TO
CIRCULATION
PUMP
TO PERFORMANCE
LOOP PUMP (OPT.)
Figure 4-3_Boiler Wiring - Circulation Pump to Junction Box
Primary/Secondary Boiler Piping
A primary/secondary piping system may also be installed to ensure proper boiler flow rates. Primary/secondary piping is also ideal for systems using a mixture of propylene glycol and water. A primary/secondary piping system uses a dedicated pump to supply flow to the boiler only. This pump is sized based on desired boiler flow rate, boiler head loss and head loss in the secondary system piping only. The secondary pump, in- stalled in the boiler piping, ensures a constant water flow rate to the boiler for proper operation. Boiler installation with a primary/secondary piping system can prevent noise problems caused by low system water flows. A primary/secondary piping system is recommended on any boiler where low water flow conditions may present an operational problem.
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