#233 Floating Suction Pickup

Figure 1

Let's take a look at one of the most common staples of the American oil industry, the in-basement oil storage tank with underground oil line and see if European technology can help in any of the problems facing us as service personnel.  In this 'standard' system oil is delivered to the top of the tank at pumping rates of 75 gpm or more.  Agitation is caused as the fuel enters the tank, mixing with the elements already in the tank which can consist of algae and sediment from tank deterioration.  Most of this sediment naturally settles to the bottom of the tank however some may float on the top of the fuel.  This mix will plug most filters, oil lines and pumps and can cause nightmarish problems if they reach the burner nozzle and flame zone.

As you look around at the North American heating industry it becomes quite apparent that heating contractors and fuel oil suppliers have embraced a tremendous amount of European technology.  When you consider that there are several European boilers on the U.S. market, a European burner that is rapidly gaining market share and several brands of radiant tubing, towel warmers, panel radiators and non-electric zone valves you can see that 'Eurotechnology' is doing quite well in North America.  Fuel oil suppliers and heating contractors have also embraced European technology with the steel covered, inert, plastic fuel tank and although more and more contractors are using this type of tank, are they really just connecting them to antiquated North American style delivery systems?  Lets take a look at alternative solutions on how to move clean oil from the storage tank and deliver it to the burner and nozzle.

The first area to look at would be filtration of the fuel.  There is no doubt that filters work and in an effort to supply the cleanest oil to the pump and later to the nozzle, many North Americans use double and triple filtration to achieve the goal of delivering the cleanest oil possible to the pump and although effective, how price efficient are these multiples of filters?

The second area to look at would be the oil supply lines.  It's amazing to consider that we continue to use a technology that puts an oil line unseen under the floor just waiting to rot out and create an environmental hazard and a nightmare for both fuel dealers and home owners, it's even more amazing when you consider the liability of this practice in regards to environmental laws and litigation against abnormal discharges.  There is no doubt that the use of oil lines covered in non-metallic tubing has dramatically reduced the possibilities of line failure and in some states the use of sleeved tubing and the oil safety valve (osv) have been mandated by code, but even these steps fail to totally eliminate the risks from ruptured or punctured lines.  When we review tanks, oil lines and filters in many different code jurisdictions a mention must be made regarding the need and use of hand-operated, fusible, spring-loaded, safety valves.  These valves are commonly called by one of their trade names Firomatic^®.

Now lets look at some solutions to these problems and how many Europeans do it.  Keep in mind that concerns for the environment are of a major concern in Europe just as they are here and that the oil heating marketplace is much larger and more competitive.  In Figure 1 we have a European style oil tank or this could be the existing tank already on the job.  Located inside the tank is a Floating Suction Kit.  The Floating Suction Kit is designed so that the pump will pick up the oil from the near top of the fuel.  The fuel is not picked up directly from the top where some debris may be floating, but rather from a few inches below the top.  As the oil continues to drop in the tank the device will follow the oil level almost to the bottom.  Through its unique 'spider legs' the last three to four inches of fuel cannot be removed.  The result is the pump will only receive the cleanest oil available in the tank.  After leaving the discharge side of the Floating Suction Kit there are two options for piping the oil supply line.

One option is to use the traditional way and to drop the oil line below the floor level risking all of the hazards previously explained.  The other option would be to exit the Floating Suction Kit, which has built into it a check valve and 45-degree angle pointing to the ceiling, and run the oil line as an overhead installation.  The line is continued until the vertical drop to the pump.  Immediately preceding the inlet to the pump the oil line will pass through a filter.  This filter may be the only filter required for the installation.  This not only filters the oil leaving the tank but also helps to provide the oil line with clean oil.  With the Floating Suction method there is no debris in the fuel, so there is normally no need to filter the oil leaving the tank.  In American systems the preferred location is always for the filter to be at the discharge of the tank acting as a tank filter with a secondary filter located at the pump acting as a line filter.

In Figure 2 the Model Floating Suction Kit is the key to enabling fuel oil suppliers and heating contractors to provide for the cleanest oil possible to leave the fuel delivery tank. The tank fitting has an internal inert ball check valve, is 2" ips and requires no bushings or adapters. The oil line fitting is 3/8" ips. The hose can be used in tanks up to 60" in height. 

It should be noted that many installers reading this text would question the use of overhead lines.  Most of this questioning is due to the service calls that can be generated by the system having not been properly bled.  The procedure is known as power vacuum bleeding and is simply a matter of after having bled the system in the traditional way to close the inlet valve at the pump, allow the pump to develop vacuum until the pump becomes noisy and then re-opening the shut-off valve and bleeding the system again. Read FIREDRAGON FIELD NOTE #6 for more info on this procedure.

Figure 2