Fridges and air conditions are something every household has, yet not many people know how they work and what they need to do to check whether they are in a good working condition. Heating, ventilation and air conditioning systems fall under the same category, as the types of testing equipment used to regulate them are very similar. They’re also known as HVAC systems, and there are certain tools – manifold gauges that are manufactured especially to ensure they work properly.
Two things that can be measured with a manifold gauge (HVAC gauge) are the temperature and pressure. Since these two are essential for air conditions and fridges, manifold gauges are the perfect tool created specifically for this task. The design ensures a correct and accurate reading of the temperature and pressure of a closed system informing the technician whether or not the closed system is working in full capacity. This HVAC measuring tool can be used in residential applications, however, it is most popular in commercial settings (that require mandatory temperature and pressure stability) such as computer server rooms, hospitals, warehouses or sensitive document storage rooms.
Proper HVAC settings ensure that a system is running in a cost-effective manner, and in order to regulate it properly, you need a manifold gauge. However, in order to ensure the right settings, you need a quality manifold gauge. Preferably one produced by a reputable company like Testo, for example, which is known in the industry as the leader among measuring solutions for different applications.
The Testo 557 is a high quality and easy to use digital manifold gauge. It has modern features like an external probe, which is capable of performing precise vacuum measurements. Furthermore, the Testo 557 can perform subcooling and superheating measurements consequently thanks to another feature, which are the two supplied temperature probe outputs. Another modern feature is the integration through Bluetooth connectivity, allowing the technician to read measurement data on a tablet or a smartphone as well as send measurement reports on site.
These features combined with the typical parts of the HVAC assembly, which is comprised of two readout gauges, the hoses and the manifold, make it the ideal maintaining, commissioning and servicing tool.
The manifold consists of three ports, three chambers and two valves. The high pressure chamber is on the right, the utility chamber is in the middle, and the low-pressure chamber is on the left. Each chamber has a port which the hose is attached to. There are also valves on both sides to control the outflow and inflow of nitrogen or refrigerant when a system purge is necessary.
There are two readout gauges, one for the high-pressure chamber and another one for the low-pressure chamber. They are often colour coded – red referring to high, and blue referring to low. The low side gauge (compound) reads positive pressure as pounds per square inch gauge, also referred to as a vacuum. The high side is attached to the air conditioner liquid line port or discharge.
The hoses used with a HVAC gauge need to be able to handle pressurized gasses that are passing through. Many problems arise when inexperienced people try to replace a quality hose with a hose with a lower psi rating.