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Hydraulic heaters maintain fluid quality and consistency: sponsored article

PROBLEM: Winter months bring cooler temperatures, often causing hydraulic fluid stored in reservoirs to become thick and sluggish. Startup can shorten the life of the system's pump because the fluid temperature is too low. What can you do?splg

SOLUTION: Install a hydraulic fluid immersion heater into your hydraulic or lube oil reservoir. A low-watt density heater is used to prevent fluid damage. Heater sizing will vary depending on numerous variables. These hydraulic fluid heaters are available with adjustable thermostats allowing the oil to be heated overnight so that you can control your start-up temperature. Weather-resistant terminal enclosures are also available allowing these heaters to be installed on outdoor equipment or in areas where wash down conditions exist.

Hydraulic fluid heaters ensure easy flow

When exposed to cooler temperatures, reservoirs storing hydraulic fluid often need to be heated. Cool hydraulic fluid can suffer from poor flow rates resulting in sluggish performance. To ensure easy flow, Warren Electric Corp.’s hydraulic fluid heaters are used to maintain the fluid at a desired temperature.

t-statWarren Electric Corp.’s tubular element heaters are designed to be directly immersed in hydraulic fluid. These heaters are often installed horizontally near the bottom of the tank/reservoir or can be inserted in a casing.

WarrenWarren Electric Corp. cataloged “HL” series heaters are designed from 0.5 to 12 kW for mounting via 2, 2½, and 3 in. NPT screw plugs as well as Warren Electric Corp.’s 4 in.-OD flange ("A/B") mount. Additional kWs, NPT or flange sizes are available upon request. Click here for WEC hydraulic heater catalog.

Warren Electric Corp. also has the capability to manufacture custom hydraulic fluid heaters to meet your unique application requirements. The Warren Electric Corp. Hydraulic Fluid “Quick Quote” Form is a convenient means to receive sizing and quote assistance. Click here for Hydraulic Fluid Quick Quote.

When determining what size heater is needed for a hydraulic fluid reservoir, variables that are taken into consideration when sizing a hydraulic fluid heater include:

  • Volume to be heated
  • Dimensions and capacity of tank
  • Thickness of insulation on tank (if any)
  • Temperature to maintain, worst case ambient temperature and desired heat-up time if tank is allowed to cool during non-operating periods
  • Available operating voltage and phase
  • Environmental operating conditions to select the proper terminal enclosure
  • Desired temperature controls (available with or without thermostat, thermocouple or over-temperature cut out devices)
  • Flow rate, desired inlet and outlet temperatures if heater will be used in a casing

Typically, hydraulic fluid heaters have a low watt density, approximately 10-12 WSI. This prevents the fluid and/or the heater from being damaged while heated.

t-statTemperature controls are needed to ensure desired temperatures are maintained when heating fluid in a reservoir. A 60° to 250°F (16° to 121°C) SPST Integral Thermostat is most commonly used. However, thermostats with other temperature ranges, thermowells or thermocouples can be used. Click here for thermostat information.

enclReservoir location and environmental conditions should be taken into consideration when selecting terminal enclosures. Warren Electric Corp.’s hydraulic fluid heaters are provided with a heavy-duty general purpose terminal enclosure. If needed, weather-resistant, dust-resistant, explosion-resistant, weather-resistant, and explosion resistant terminal enclosures are also available, upon request. Click here for information on terminal enclosures.

Heaters with casings are referred to as circulation heaters. Hydraulic fluid enters the casing through an inlet, is heated as it flows past the elements, and then exits the casing via an outlet. Circulation heaters are available with or without insulation. Warren Electric Corp. is also able to supply you with a casing designed for your specific application.

logoFor more information, call Warren Electric Corp., 36 Franklin StreetWarren, RI 02885, at 401) 245-3700, fax (401) 245-9331, email [email protected], or visit

Additional resources

Hydraulic heater catalog link:

Quick Quote:

Link for thermostats

Link for terminal enclosures

Link for

Link for casings