Ammonia Refrigeration Systems.

Choosing the right ammonia equipment for your process

Most ammonia enquiries start with one of three questions: how much heat has to be rejected, how cold the product has to get, and how the liquid reaches the evaporator. The answers point to different equipment, and getting the combination right matters more than any individual component's rating.

Heat rejection

Evaporative condensers reject heat using the combined effect of water evaporation and air movement, which lets them run at a lower condensing pressure than an air-cooled equivalent — and condensing pressure is what your compressor power bill is really made of. We build them in two configurations. The mixed flow design uses laser-welded stainless steel pillow plates and suits plants where footprint and water quality both matter. The counter flow design uses an SS-304 tube coil block and is available from 100 kW to 1600 kW of heat rejection, in multi-section construction so large units can still be transported and installed on a working site.

Cooling and freezing

Ammonia air cooling units transfer heat through stainless steel tubes and aluminium fins, operating from −5°C down to −55°C. Fin spacing is the decision that gets made too quickly: wide spacing for freezer rooms where frost builds, tighter spacing for chillers where it does not. Defrost method follows from the same reasoning — electric, hot gas, water or air, each with different consequences for room temperature stability and running cost.

For liquid chilling, falling film chillers hold water within half a degree of freezing by flowing a thin film across a pillow plate surface. The thin film means a small temperature difference does the work, so the evaporating temperature stays high and the compressor works less. Where the load is intermittent rather than continuous — a dairy that chills hard for four hours a day — a plate ice bank stores cooling as ice during off-peak hours and releases it on demand, which lets you size the plant for the average load instead of the peak.

Liquid management

An ammonia plant is only as reliable as its liquid handling. Our pressure vessel range covers high and low pressure receivers in 26 standard models, oil separators, gas and liquid coolers, and horizontal and vertical accumulators. Shells up to 300 mm are welded pipe; above that, rolled plate. Every vessel is hydraulically and pneumatically tested before it leaves the works.

Liquid overfeed systems push more liquid through the evaporators than will evaporate, which keeps the tube surface fully wetted and stops oil from logging in the coils. The result is higher plant efficiency, no liquid slugging back to the compressor, and hot gas defrost that actually works. Our sealless liquid ammonia pumps are available from 2 HP to 10 HP, with no shaft seal and no external lubrication — the pumped fluid cools and lubricates the motor.

Built in-house, tested before dispatch

Pillow plates are laser welded on our own equipment, a process we developed further in-house so that relatively thin plate still withstands high operating pressure. Stainless tube joints are orbital welded for consistent, leak-free results across every joint rather than every welder. Coils are pressure tested individually. This matters because the failures that hurt in industrial refrigeration are not dramatic — they are slow leaks in inaccessible joints, found months later as falling capacity.

Prime Coil & Condensers Pvt. Ltd. was founded by industry veterans Neeraj Checker and Vikram Luthra, and supplies across India and to export markets.