It doesn’t take much for a refrigeration system to run inefficiently: Some crisp packets and other rubbish blown onto the condenser, some ice build-up on the evaporator coil, a door being left open a bit longer than necessary. Any one of these things on their own will adversely affect the efficiency of a refrigeration system, and all these things put together will have a compound effect on the efficiency. It goes without saying that as the efficiency of the system decreases, the energy usage increases, the energy costs increases and so the system costs a lot more money to operate than it should. The Carbon Trust states that for some organisations, refrigeration costs can represent over 50% of their energy bill costs. We’ve have looked at three simple tips that can help deliver big energy savings…
- Clearing rubbish…
Is your system not maintaining temperature? This may be caused by outside debris. Crisp packets and other rubbish blown onto the condenser will restrict the air flow over the condenser. The air restriction means that the heat cannot be carried away from the condenser and so the temperature of the gas is increased and the pressure on the head of the compressor rises. With the increased temperature and pressure, the compressor must work harder and longer to maintain the temperature inside the fridge.
- Monitor the ice build-up…
Ice build-up on the evaporator effects the evaporator function in two ways. Firstly, the ice build-up will block the evaporator and restrict the air flow so that the heat cannot be carried into the evaporator efficiently. Secondly, the ice on the evaporator also acts like an insulator hindering the evaporators ability to absorb heat.
Ice build-up can be caused by various things such as; poor air flow, dirty coil and a damaged fan. Inspecapedia discusses how the ice blocks the air flow through the coil, reducing air output; if the ice formation is extreme nearly all of the airflow across the coil is blocked. The system will continue to run but will not produce cool air flow.
- Keep the door sealed…
So, what about leaving the door open? This really is a ‘no brainer’ even without understanding the full effects. Firstly, while the is door open, your system is not only trying to refrigerate the cold store, it is also trying to refrigerate the area outside the store. And secondly, the warm air entering the store contains moisture which condenses and freezes onto the evaporator, causing the ice build-up. Air ingress accounts for around 30% of the total heat gain into cold stores. Liebherr discusses how every time the refrigerator door is opened, cold air escapes and warm ambient air enters, to compensate for the temperature increase in its interior, the refrigerator must then use energy to bring the temperature back down.
Although it is important to make sure the door is closed as much as possible, warm ambient air can also enter if a seal is broken. Always check door seals or gaskets to make sure they are in good condition. A broken seal is equivalent to leaving the door open. Liebherr discusses that the seal is used for insulation purposes and prevents heat exchange between the ambient air and the refrigerator. It is important to regularly check that the seal is fully intact. To check whether the seal is working effectively, if you don’t see light, the seals should be in good shape.
Finally; the great thing about saving energy from the three things mentioned is that it doesn’t take an engineer to make any of the adjustments. The three simple tips of ensuring your condenser is kept clear, the evaporator is free of ice and ensuring the door is sealed, could have an affect on lowering your running costs and ensuring your equipment will last longer, with reduced reactive maintenance costs.