Let's say your thermostat has been set at 70° and your living room has reached that temperature. The thermostat sends a signal to the zone valve that tells the zone valve to close the water flow to that room. However, there are still other zone valves open because the temperature in the back bedrooms have not reached their temperature setting. The pump is still running the other zones in your house but since the living room zone valve has been closed the pressure now increases on the rest of the system. The Magna pump detects the change in the electrical amperage to the now closed zone valve and automatically compensates and slows the pump speed down, reducing the load on the motor and thereby reducing your energy consumption. This is all done, automatically, for every zone valve on your system! The AUTOADAPT® feature even keeps a record of your normal usage pattern and will automatically adjust to keep your entire heating system working as efficiently as possible while keeping the comfort level of your living space exactly where you want it to be.
These MAGNA and MAGNA3 pumps are commonly used in hotels, schools, hospitals, apartment buildings or other facilities that use hydronic fan coils to heat many separate rooms. They are also a brilliant choice for new construction installation in large homes or for existing heating systems that need quick pump reaction to flow rate demand changes. The pump will automatically react and adjust to flow rate changes and increase or decrease head pressure without the need to use expensive bypass valves. These pumps can immediately adapt to operate at the maximum pump curve as needed.
The Magna pumps have an operating panel that shows the pump's basic essential performance features clearly indicating flow rate and operating level of the pump compared to its maximum capacity. The pump performance can also be manually adjusted instantly with one press of a button. An automatic night time setback (pump duty at low performance) can be selected by pushing the mode button on the control panel. This feature will allow the pump to change automatically from normal duty to night time duty when an integrated temperature sensor registers a drop in temperature of more than 18°F. to 27°F. inside the hydronic heating piping within approximately 2 hours. This night time duty slows the pump down to the minimum circulation flow of the system. Most people turn their thermostats down or off at night so the pump will not need to operate at their normal higher flow rate. The changeover back to normal duty happens without a time lag when the temperature increases by approximately 18°F.
The MAGNA and MAGNA3 variable-speed wet rotor circulators are reliable, intelligent and powerful, yet energy efficient. Wet rotor circulators are designed to be water cooled and at the same time lubricate the shaft and bearings as the pumped water surrounds and moves past the rotor. Since the magnets are positioned in the rotor, no brushes are needed, like conventional motors. Permanent magnet motors can produce from 35% to 40% more power than conventional type motors, but at a lower electrical power consumption. How smart is that? All MAGNA pumps are the most efficient pump you can currently purchase.
Cast iron pumps are used for closed systems such as hydronic or radiant heating. Stainless steel pumps should be used for open systems since they are not effected by the introduction of oxygen (air) into the system. The Grundfos Magna pumps are offered in cast iron or stainless steel.
Now, here is where your thinking plays a part. It is important for you to choose a pump with a duty range that falls within the same range as the sizing of your system. The duty point is the point on the pump curve chart where the flow and head meet that matches the requirements needed for your circulating system application. We show the head pressure and corresponding GPM flow rate for both the proportional differential pressure and constant differential pressure on the pump curve charts for the original MAGNA pumps below.
The MAGNA3 Series pump curve charts can be accessed on the Magna Pump Systems main product page under the model numbers listed for each of the many pumps offered.
MAGNA and MAGNA3 pumps are designed to circulate water with hardness not greater than 14 grains per gallon or with a mixture of water containing not more than 50% glycol. If your water has a hardness rating of 14 or greater then a water softener would be needed to reduce your hardness level. Magna pumps must not be used to circulate or transfer flammable liquids such as gasoline, kerosene or diesel oil.
Grundfos MAGNA and MAGNA3 pumps can be used with the state of the art Grundfos GO Remote app. The MAGNA pumps can be fitted with optional expansion modules so the pump can be monitored or controlled by an external controller with the use of signal transmitters. MAGNA3 pumps can be monitored or controlled by wireless communitcation means without adding expansion modules.
You can view the complete MAGNA3 technical information booklet for more detailed information.