dimax knowledge Base

  • Most atmospheric boilers and water heaters burn Natural Gas to transfer heat to water. Once the gas it burnt and heat transfer is complete, it must be exhausted out in to the atmosphere. It is important to ensure that enough heat remains in the exhausted or flue gas to maintain it as a gas for […]
  • A heat pump is a device that uses the refrigeration cycle for heat recovery. Normally thermal energy transfers from a hot body to a cold body. A heat pump uses external energy to transfer thermal energy in the opposite direction, that is to absorb heat and then reject it to ‘heat sink’. The simplest example […]
  • Building Automation Systems (BASs) are connected to equipment in such a way that they do not interfere with safety control devices, such as the high temperature limit of a boiler.  In addition to that, sometimes they are wired in such a way that a boiler’s built-in thermostat has a way to affect boiler operation even […]
  • When the water entering a boiler is below 130 degrees F (55 degrees C), condensation forms inside the boiler.  Some boilers, called Condensing Boilers, are built to withstand this condensation and use it to improve the efficiency of the boiler by approximately 5-8% whenever cold water is entering it.  However, since Condensing Boilers are more […]
  • There are a number of safety controls internally built into the boiler. Each of the safety controls has a particular identifying code that can be seen on the boiler’s controller interface or screen. The user manual or mechanical equipment data sheet of your boiler should have a legend where you can match the code to […]
  • In order to assess whether or not the heat exchanger is performing properly, the medium needs to be flowing through both the Primary and Secondary sides.  The flow of medium should be somewhere close to the design flow rates, which are typically identified in the specification sheets of the heat exchanger.  This isn’t always easy […]
  • The purpose of a heat exchanger is to transfer heat from one medium to another.  Most often, heat exchangers transfer heat from water-to-water, air-to-air, water-to-air, or refrigerant-to-air.  An example of a water to air heat exchanger is a heating coil.  The two sides of the heat exchanger are referred to as Primary and Secondary. The […]
  • Domestic hot water systems in apartment buildings are typically piped so that the hot water is distributed into vertical risers throughout the building.  For example, if your building has 12 apartments per floor and 8 floors, there will be a typically be one riser that services apartments 101, 201, 301 … up to 801; another […]
  • Often Building Automation System installers use a Current Sensing Relay (also known as Current Switch) to indicate the status of a piece of equipment such as a pump or fan.  The Current Sensing Relay is triggered when an electric motor draws current, which is the case when a pump motor is running.  However, just because […]
  • Boiler could be in alarm and the alarm might need to be manually reset before the boiler can run again. The heating valve on your AHU or MAU might be shut close, either due to mechanical failure or due to incorrect automation/programming logic. Heating might be enabled and the boiler might be running, but the […]
  • There could be a number of reasons for this: The boiler burners might need replacement. The circulation pumps might not be running properly. If there is some kind of diverting or mixing valve in the heating system, then this valve might be stuck in one position.
  • If your boiler is oversized with respect to the requirements of the building then it can run very efficiently when there is a high heating demand and it can produce heat efficiently in large quantities. However, if there is not a lot of demand for heating like, for example, in the shoulder season, then the […]
  • If your heating is working for all areas except a single particular area then there could be a few reasons for why this is happening. If the building has Variable Air Volume units (VAVs) or Constant Air Volume units (CAVs), then it could be that the VAV/CAV to that particular area is malfunctioning, and its […]