PB Heat Gas Boiler manual System Piping Freeze Protection, Pinnacle Circulator Sizing Graph

WATER PIPING AND CONTROLS

Figure 3.2: Pinnacle Circulator Sizing Graph

	21
	20
	19
	18
	17
	16
Head)	15
	14
	13
of
	12
(Feet
	11
Drop	10													PI-T50
	9
Pressure
	8
	7													PI-T80/80
	6
	5													PI-140
	4
	3													PI-199
	2
	1
	0
	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22

Flow Rate (GPM)

D. SYSTEM PIPING E. FREEZE PROTECTION

1.Figure 3.3 shows a single boiler with two zones. In this application, the Peerless Partner indirect water heater and the single heating zone require similar water temperature.

2.Figure 3.4 shows an additional zone in which baseboard radiation is the heat load. This zone also requires water temperatures similar to the indirect water heater.

3.Figure 3.5 shows diverter tees used in combination with conventional hydronic radiators on an additional zone. A second boiler is also added to the system. Notice that the boilers are piped in parallel on the secondary loop. It is important that the common headers are sized to match the system piping. Smaller headers may result in flow fluctuations through the boilers.

4.Figure 3.6 shows a system in which several different types of loads and multiple boilers are shown. This system illustrates how different temperature zones can be supplied from the same source by mixing down the temperature using a three way mixing valve. Radiant flooring typically requires much lower temperatures than baseboard radiation and indirect water heating. Notice that a third boiler is included in this system.

5.Figure 3.7 shows zone valves used in place of zone circulators. Notice that this system utilizes reverse return piping which makes it easier to balance the system. If the heating zones are very different in length, the balancing valves on the return side of each loop are required.

1.Glycol for hydronic applications is specially formulated for this purpose. It includes inhibitors which prevent the glycol from attacking metallic system components. Make certain that the system fluid is checked for the correct glycol concentration and inhibitor level.

2.Use only inhibited propylene glycol solutions of up to 50% by volume. Ethylene glycol is toxic and can chemically attack gaskets and seals used in hydronic systems.

3.The antifreeze solution should be tested at least once per year and as recommended by the antifreeze manufacturer.

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