Transformer Breathers

    Transformer Breathers

    The R Series Transformer Breathers that, we here at Protection Experts Australia offer, are manufactured from UV stabilised poly-carbonate and are available in three different sizes. The clear polycarbonate body allows for clear visibility of the desiccant charge and enables users to check desiccant condition with ease. The unit is mounted from a ¾” female pipe thread connection at the top of the breather. This connection point is also used for filling and emptying the desiccant within the breather. Two-way, low pressure valves are fitted in the base of the breather to ensure that the atmospheric air enters the desiccant when a negative pressure differential occurs within the equipment being protected.

    Selection Guide

    The following data should be used for the basic selection of transformer breathers.
    In order to assess the size of the breather, the air volume above the oil in the conservator tank is the most important factor to consider. The quantity of oil and the transformer rating is of secondary importance.
    The daily breathing rate is based on the assumption that there are two temperature drops of 8°C per 24 hours. The breathing volume change which occurs during the pump start-up is not taken into consideration.


    The transformer breathers are supplied with a threaded sealing plug screwed into the top moulding to prevent any water vapour ingress whilst in store. This plug should be removed immediately prior to the unit being fitted to the air vent pipe of the transformer reservoir tank. Fit the breather and tighten using the spanner flats provided at the top of the unit. Maximum torque on threads is 9Nm/80lbfin.


    Replacing Spent Desiccant

    The only maintenance necessary is replacing the spent desiccant as detailed below:

    1. Unscrew the breather from the vent pipe.
    2. Remove the perforated cover in the top moulding and empty the spent desiccant from the container. This material may be disposed of in a normal landfill site.
    3. Fill the container with active orange desiccant, lightly tap the container to settle the desiccant and top up if necessary. We supply the desiccant refills  for our Transformer Breather range.
    4. Replace the perforated cover and screw the recharged breather back onto the vent pipe.


    Periodic inspection should be carried out to monitor the condition of the desiccant charge. The breathers are filled with beaded Envirogel desiccant. This material changes colour from orange to green as it becomes saturated with water vapour. When the colour change reaches the indicator line on the desiccant container it should be recharged with fresh desiccant or the complete assembly should be replaced.

    Desiccant Refills

    Transformer Breather brochure

    Transformer Breather brochure

    Envirogel refills – Part No. BL/D6331 offers capacities ranging from 0.5 to 50Kg.

    What is the function of Transformer Breathers?

    As the name suggest “BREATHER” helps the transformer to breath i.e it helps to provide the flow of air from inside the transformer to atmosphere, as well as the flow of air comes from atmosphere (outside) into the transformer.

    The BREATHER is basically a cylindrical vessel in which silica gel(Best adsorbent) is present through which non-moist air flow occurs in the transformer.

    What is the function of a breather in a transformer?

    The function of breather in a transformer is to filter out the moisture from air. The Breather consist of silica gel which absorbs the moisture from air.

    Quick Links:

    Blue Silica Gel Data Sheet (MSDS)

    Orange Silica Gel Data Sheet (MSDS)

    How to fill a Breather unit.

    Showing all 7 results

    R Transformer Breather (small)

    $155.00$169.00 excl. GST

    Includes Silica Gel Pak 0.6kg BLD6586RF (Orange or Blue)

    R1 Transformer Breather (medium)

    $198.00$229.00 excl. GST

    Includes Silica Gel Pak 1.2kg BLD6942/01RF (Orange or Blue)

    R2 Transformer Breather (Large)

    $229.00$259.00 excl. GST

    Size R2 – P/N BLD6942/02

    Includes Silica Gel Pak 1.9kg P/N BLD6942/02RF

    Indicating Silica Gel in resealable packet (600g)

    $28.00 $10.00 excl. GST

    Compatible with the R Transformer Breather.

    Packaged loose in a resealable pouch.

    Indicating Silica Gel in resealable packet (1.2kg)

    $55.00 $19.00 excl. GST

    Compatible with the R1 Transformer Breather.

    Packaged loose in a resealable pouch.

    Indicating Silica Gel in resealable packet (1.9kg)

    $69.00 $27.00 excl. GST

    Compatible with the R2 Transformer Breather.

    Packaged loose in a resealable pouch.