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2013 Solar Products Catalog
Specializing in Sustainable Solar and Wind Energy Products to Brighten your Life!


Circulating Pumps

Pumps used in solar heating systems are called hot water circulator pumps. Many pumps are not designed for more than 120°F and will fail prematurely if used in heating systems. Solar heating pumps are sized to the application based upon head and flow rate. The head of a pump is the power it has to overcome both the vertical height that the liquid must be pumped and the friction of the liquid against pipe walls.  Frictional head loss is not significant except in very large piping systems. Hot water circulators are designed with a wide range of head and are classified as low head (3' to 10'), medium head (10' to 20') and high head (more than 20'). Low and medium head pumps are normally used for closed loop (glycol and DHW) systems. High head pumps are used for drainback systems and large baseboard or radiant floor heating systems.

Pumps for domestic hot water or other open loop systems should have bronze or stainless steel housings to prevent scale from building up. Pumps for closed loop systems may have iron housings although a bronze or stainless steel housing will normally last longer.

Pumps and Flow Rate
If the system controls are working correctly, an inoperative pump may be due to a stuck impeller, a burned-out motor, or a broken shaft.  These types of problems may be expected over the lifetime of any component subjected to the temperature and cycling stresses of a solar system pump. Even though a solar pump is operating and is being controlled correctly, there still may be problems with the actual flow rate in the collector loop. If the pump has been sized to just barely overcome the pressure head of the collector loop, an unexpected added resistance can stop all flow through the collector. For example, air in the fluid may, over a period of time, collect in a section of piping, especially if it cannot escape through a vent to the atmosphere. This "air lock" can prevent any flow if the pump does not have the capacity to compress the air completely and force it through the system. In an indirect system, loss of collector fluid pressure can also prevent flow in the collector loop. The pump is generally not sized to overcome the static head or pressure due to the difference in height between the top and bottom of the collector loop. It is usually sized to maintain the desired flow against the dynamic head or pressure due to the resistance to flow in the pipes, fittings, and valves. If the fluid pressure to overcome the static head is lost, then the pump may not be able to maintain flow against the combined static and dynamic head of the system.



Model 006-BC4 $ 289  
1/40 HP motor is impedance protected. Bronze body with 1/2" sweat fittings. Delivers flows to 12 GPM; head to 10 feet. Designed for domestic hot water systems and circulation of open fresh water and potable water systems.

NSF rated for potable water.

Model 006-B4  $ 289  
This pump is the same as 006-BC4 but has 3/4"sweat fittings.
Model 006-BC4-1 $ 289  
This pumps is the same as 006-BC4 but has 1” threaded fittings.
Model 008-F $ 380  
Cast iron flanged body. Flows to 14 GPM and head to 16 feet, 1/25 hp. Designed for use in closed loop solar systems and hydronic applications where higher head is necessary. 
New installations require a flange set.
Model 008-B $ 479  
This pump has the same GPM and head as the 008F pump but is a bronze body. Designed for use in open loop solar systems, DHW water circulation.  
New installations require a flange set.

NSF rated for potable water.

Model 009-F $ 380  
Cast iron flanged body. 27 foot head at shut off; 1/20 HP motor. Designed to fit drainback systems that require a low flow, high head pump.
New installations require a flange set.
Model 009-B $ 450  
Bronze flanged body. 27 foot head at shut off; 1/20 HP motor. Designed to fit drainback systems that require a low flow, high head pump.
New installations require a flange set.
Model 0011F $ 275  
Cast iron flanged body. 30 foot head at shut off, 28 gpm maximum flow. Designed to fit heat exchangers systems and large radiant heating systems.
New installations require a flange set.
006-BC4  $ 127

006-B4 $ 127
006-BC4-1 $ 127
008-F $ 109
008-B $ 142
009-F $ 173
009-B  $ 206
0011-F $ 226
Model UP26-96F $357  
Cast iron, 1/12 HP; pushes to 31 foot head.
Designed for collector loop on drainback type solar systems.
New installations require a flange set.
Model UP15-42F $240  
Cast iron, single speed centrifugal pump.
Designed for domestic and light commercial closed loop water system applications. Can also pump 50% glycol solutions. 1/25 HP; pushes to 15 foot head.
New installations require a flange set.
Model UP15-18SU $298  
Stainless steel, 1/25 HP; pushes to 7 foot head.
Designed for domestic hot water system applications.
New installations require a flange set.

NSF rated for potable water.


Iron  $36  
Bronze $75  
Set of 2 - 3/4" pipe thread bronze flanges for all flange (F) pumps. Also 1” threads available
EL-SID Busrhless Water Circulators

These tiny brushless, magnetic drive circulators can be driven by PV modules or 12 volt batteries for closed-loop circulation in solar water heating systems, individual space heat zones and individual loop radiant floor loops. Use of several small pumps in a radiant floor system allows each loop to be controlled by a different thermostat.

Model SID10 is designed to be powered by a 10 watt PV module, in open loop systems and can pump 3.3 gallons per minute at no head and ˝ GPM at 2.5 feet of head at 17 volts input.

A 20 watt module should be used for glycol systems. It can circulate water in a well designed solar water heating system with two 4 x 10 collectors. Model SID10B is designed to be battery powered and has the same specifications at 12 volts.

Dimensions: 4" x 4" x 5".

Spec Sheet

Model Number

Flow (GPM) at No Head

Volts (Max)

Head (ft)

Weight (lbs.)




EL-SID 10P-12







EL-SID 10B-12







EL-SID 10B-24







EL-SID 20P-12







Hartell DC Circulator Pumps

This pump has an electronically commutated, high efficiency brushless motor with a 30,000 hour life expectancy. It may be operated from an 20 to 22 watt solar module or directly from a 12 volt battery system.

They work great for closed loop solar water heating systems and radiant floor heating.

The graph shows this pumps performance at various heads and flows, at different input voltages.

NSF rated for potable water.

Has a 1/2 inch inlet and outlet

5.25 x 9


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This page designed and maintained by Terry R. Wolff Last up-dated on December 17, 2013
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