Blodgett KPT-DS User Manual

11

No preventive maintenance is required other than adhering to the Cleaning Procedure
instructions.

If a leak occurs through the valve steam, replace the “O” ring.  If the leak can be attributed to
faulty sealing occurring between the stem disc and valve seat, then quite often this problem can
be corrected by cleaning off the dried on food residue with an extremely fine emery cloth or the
rubber vulcanized stem piece has been damaged and must be replaced.

If the cooking time is abnormally slow then the difficulty may be due to insufficient steam
pressure and/or volume.  First determine that pressure on incoming steam line at kettle is within
5 p.s.i. of rated kettle pressure.  Note that pressures approaching the rated kettle pressure are
liable to set off the safety relief valve.  If required pressure is available to kettle, then possibly
volume of steam is not sufficient.  Minimum 3/4" pipe size is required to the kettle but if the steam
generating source is at a great distance from the kettle, larger pipe will be required.  Finally, the
core of the steam supply pipe may have debris or scalants that impede steam flow and will
require disassembly and inspection.

It is recommended that the “optional” steam trap assembly be installed.  This should be plumbed
to the exit end of the kettle.  The thermostatic trap is a mechanical device that closes on high
temperature and opens when the temperature drops, allowing the water which formed from
condensate to exhaust but retain the steam under pressure.

The temperatures required for the cooking process to function adequately must be greater than
the boiling point of the liquid food product, that is, water.  The greater the steam pressure used,
the higher the temperature and the quicker the cooking process.  For example, steam
pressurized at 30 p.s.i. reaches a temperature of 274 degrees Fahrenheit (135 degrees Celsius).
Since air is an unsuitable media through which heat may be transferred, the air should be
exhausted from the jacket by opening the pressure relief valve until the air has been completely
replaced by pressurized steam.

In the initial stages of the cooking process when the steam comes in contact with the cold kettle
bowl surface, it condenses and forms a large amount of water. The condensate water must be
removed from the kettle jacket in order for the kettle to function adequately. The ball valve
located at the base of the kettle jacket may be opened to remove the water. It may be necessary
to repeat this procedure several times depending on the number of batches being cooked as
each batch will create condensate. If the kettle appears to be slow in heating, this would indicate