How to Measure the Amount of Water Contamination in an Oil Storage Tank

Detect & measure the amount of water contamination in an oil tank:

This article explains how to test for the presence of water in oil tanks, and how to measure the level of water that has accumulated in an oil tank.

We describe the use of water finding pastes and where to buy those test materials and we suggest some simple do-it-yourself methods for checking for water contamination in heating oil or in the oil tank.

How to Measure the Level of Water Contamination in an Oil Tank

Oil storage tanks would ideally be tested for water accumulation at every oil delivery, but as that simply is not going to happen, you should ask your oil company to assess the amount of water in the oil tank at least once a year by using one of the methods discussed below.

A simple method that can be used on oil storage tanks whose fill pipe is located directly above the tank is to insert a dipstick into the oil tank after coating the dipstick end with a water-finding paste. (photo at left).

A similar test for oil tanks whose piping does not permit use of a dipstick makes use of a string and weight and water finding paste.

Where to Buy Oil Tank Water Finding Paste or Water Indicating Pastes

• Water finder paste & dipstick for use in heating oil tanks: using a water finder paste on the end of a stick. Water indicating paste also called water finding paste or water finder paste, is coated over the bottom few inches of an oil tank probing stick or onto a string or flexible tape which can be inserted into an oil tank. The water indicating paste changes color (typically white to red, green to red,or pink to white) to indicate the depth of water in the oil tank.
  
  You can ask your oil company to handle this if you don't have a stick, string, or tape or tools to open an access plug on the top of your oil tank. This method works best if the oil filler pipe is a straight shot down into the oil tank, If there is not sufficient overhead room to insert the long stick, such as with outdoor and buried oil tanks you'll need to use a string or tape which you coat with the water indicating paste.
  
  Here is a list of water and oil indicating pastes that will detect water in home heating oil tanks whether they are buried or above ground, outside, or indoor tanks:
  
  
  • Eastern Water Indicating Paste (in a tube, turns red in presence of water)
  • Eastern Oil Indicating Paste (oil finding paste) in a jar, used to indicate the height of heating oil, diesel oil, kerosene, gasoline, etc, turns from pink to white).
  • Kolor Kut water Indicating Paste
  • Sar-Gel gauging paste turns bright red where it contacts water
  • McCabe Gauging Paste  - a water level indicating paste, turns from green to red when immersed in water for 30 seconds or more. McCabe also makes a gasoline indicating paste which is purple and shows a line where gasoline is encountered.  
    
    Here are some online sources where you can purchase these products (we have no financial relationship with any product or service discussed at our website:
  • www.marineservicesinc.biz/ - Marine Services, Inc.
  • www.wlwalker.com/sites/WLW/sp_products.asp?groupid=GAUGE - W.L. Walker Co.
  • www.lindequipment.net/   - Lind Equipment
  • www.icllabs.com/Gauging%20Pastes.htm - ICL Calibration Laboratories
  • www.china-tapemeasure.com/oil-tape-measure-fibre-glass-tape.htm - Eastern Tape Measure

Other Methods for Detecting Water Contamination in a Heating Oil Tank

• Other water sensing products: Other special products are available such as a sensor connected to a string or wire that can be dropped into an oil tank to check for water contamination. Water alarm devices are also available.
• Visual Check of the oil filter at the oil burner: inspecting in the oil filter at the heating equipment can indicate a history of water passing from the oil tank towards the oil burner. Water in the oil filter, or rust therein, would be an indicator of water passing through the system.
  
  As we discuss at OIL TANK LEAK TEST METHODS, A neat way to look for a history of water in the heating oil storage tank is to check the oil filter canister itself. Many oil burners are protected by a heating oil filter installed either at the tank or at the oil burner. (Every heating boiler burning oil should have one of these filters installed to protect the equipment.)

  If the oil tank has a high level of water, especially if the oil lines run to the oil burner from the bottom of the oil tank, some of that water will have been making its way to the oil burner where, en route, it is (usually) trapped in the oil filter. If you open an oil filter container and see that its metal parts are rusted, or that there is a lot of rusty sludge in the bottom of the filter holding canister, the oil tank needs to be checked further for water

Ask your oil company service technician to check the oil filter for evidence of water or rust, or if you've had heat outages ask if water in the oil could be a contributor or cause.

This article series explains the problems caused by water accumulation in oil tanks, how water gets into the oil tank, how to measure water in the oil tank, how to remove water from oil storage tanks regardless of whether the oil tank is indoors, outdoors above ground, or buried, and how to prevent water from getting into an oil storage tank.

We explain how to test for or visually check for water in a buried or above-ground oil storage tank, and how to get water out of an oil tank. Extensive free un-biased oil storage tank inspection and testing advice for property buyers and owners is provided at this website.

This website provides detailed information about underground (buried) oil storage tanks (USTs), aboveground oil storage tanks (ASTs), above ground fuel storage tanks, reporting and cleaning up oil tank leaks, and choosing among oil tank leak testing methods.

Aboveground Oil Storage Tank Water Contamination Articles

• OIL TANK WATER CONTAMINATION
  • ABOVE GROUND OIL TANK WATER ENTRY
  • BURIED OIL TANK WATER ENTRY
  • OIL TANK WATER DETECTION
  • OIL TANK WATER PREVENTION
  • OIL TANK WATER REMOVAL

...

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