It is mind-boggling how much HVAC and refrigeration equipment is involved in dairying.
Starting with refrigerators, milk vats, heat exchangers, chillers and silos, the list goes right through to the air-conditioning plants that keep everything comfortable and hygienic.
Unfortunately, all of that equipment has a great potential to leak refrigerants someday, which can not only cost more in energy bills (because the equipment has to work harder to achieve the same result) but also harm the environment.
Lack of efficiency on a vat, due to a low refrigerant charge, will increase running time and cost and also has the potential of causing the issue of over temperature milk.
Most HVAC/R units eventually leak because of mechanical wear of components, vibrations, and various forms of corrosion. The time taken for the system to completely lose its refrigerant charge can vary from one to 30 years.
Then comes the decision a facility manager or farmer must make with the service contractor—repair, component replacement, or total unit replacement.
There is, however, a fourth option that might be one of the best-kept secrets in maintenance today, a HVAC/R system sealant that can stop leaks permanently and seal future leaks for several years.
Dairy processors and farmers have applied this Super Seal sealant to their milk vats, for example, saving maintenance, time and money, says the managing director of the Australasian distributor for the technology, Mr Gary Oborne, Managing Director, GO Distribution .
The sealants involved are a blend of organosilanes that react to moisture. When injected into an HVAC/R system, they move freely through the system with the refrigerant and oil. In a leaking system, the refrigerant and sealant leaks out of an exit hole.
When the refrigerant leaks out of a hole of 300 microns or smaller, however, the reaction with atmospheric moisture causes Super Seal to crystallise into a hardened bond around the exit point, thus stopping the leak. This is very similar to the human body and how blood clots to stop the bleeding of a wound.
One of the great strengths of this method of repair is that users don’t have to dig through concrete and steel or cut through metal to get to pipes that may be buried within structures, costing money to access.
The time taken to repair a leak in a system using Super Seal is far less than having to cut open the vat or spend hours searching for that elusive, inaccessible leak. The cows won’t wait for a few days without being milked while the vat is out of action.
The technology has been proven in recent applications involving the dimple plates in the evaporator of a milk vat, which are renowned for their propensity to leak. Normal rectification for a leaking dimple plate is to replace the entire milk vat, an extremely expensive exercise.
Finding the leak in a dimple plate is very difficult as they are sealed units, so it requires the use of a stethoscope to detect the approximate area of the leak and then cutting through the base stainless steel plate to then weld the point of leak.
To access the base of the vat requires removal from the refrigeration system and turning the vat over, at times with the necessity to use a crane, thus incurring additional expense. The making of Ben Hur would have been simpler!
Super Seal not only fixes many problems simply, but also residual sealant remains active in the system and immediately stops future leaks as they occur.
“We know from experience gained with the product that it can be used to revitalise equipment that could otherwise end up prematurely in the junkyard,” said Mr Oborne.
“Whether it is applied to a milk vat, the beer fridge or massive process plants, it has proven potential to save users considerable downtime and money.”