Thursday, 24 July 2014

How to Assess Heating and Ventilation Loads Before Buying the HVAC System

When it comes to selecting the HVAC system, heating and ventilating loads play significant role. Several environmental factors and design computations determine these loads. So how to know the real significance of heating and ventilation load assessment. Continue reading for an in-depth study.

If you have decided to install an HVAC system in a particular building, then an estimation of heating and ventilation loads should be done first. Based on the outcome you decide, the design and type of HVAC system to be installed. Only an accurate assessment of these loads ensures precise selection of the heating and ventilation system for that building. This way you can be sure that the HVAC system will function consistently and guarantee variable productivity, which is proportionate to the building’s heat load whenever the climate changes. Now the big question is how to assess heating and ventilation loads. Before you take out the calculator, here are some factors needed to be considered while assessing the load. 

  • Know the amount of heat which is spread through areas that are not directly heated.
  • Have an idea about the amount of heat needed to turn that air hot which has penetrated through door, window cracks or through entrances.
  • Know about heat which is needed to make that air hot that has entered the building mechanically as ventilation air.
  • Take into account various other loads.
In order to precisely determine the heating load, you should have an idea of the constant average temperature during night time of the winter season. Also, take into consideration constant supply of heat, if any, is present all the time. Quantity of heat which the building accumulates along with energy of cooling equipments has to be considered for specific design calculations.

It always helps if you have ideas about how to do the estimation of heating loads. Few steps are discussed below.

  • Do conduct an assessment of weather conditions which usually prevail outside the building. For this, you should take into account temperature, humidity and wind’s speed.
  • What kind of indoor air temperature you desire to maintain.
  • Analyze general temperature of adjacent locations that are not heated.
  • Determine heat transmission coefficient.
  • Determine outside areas through which heat gets dispersed or rather wasted.
  • Take into account heat transference losses which happen through bricks, glass and the building base.
  • You should also calculate heat loss which happens through basement areas.
While calculating design and selecting the right HVAC system, structure of the building and for what purpose it is being used, should be assessed accurately.  Its exposure to wind, whether it is receiving direct sunlight, which part of the day this building is mostly used and its period of occupancy, all these factors play crucial roles too.

Thus to sum it up, if you want maximum energy and cost efficiency from the HVAC system, then do carry out thorough assessment of several design and environmental factors. Of course you can talk to an expert for helpful guidance in this regard.

Tuesday, 15 July 2014

Basic Steps to Clean Air Conditioner Coils

Air conditioner coil is an integral part of the cooling system. This coil performs a very significant function that of exchanging heat from inside air to outside air. Basically, there are two types of coils used in an air conditioning system. The condenser coil, made of aluminum, covers the air conditioner compressor from outside, whereas the evaporator coil is attached at the main duct junction, inside the air conditioner itself. Thus, it is the evaporator coil whose efficient functioning matters the most.

Maintenance of air conditioner coils should be done carefully. To simplify the cleaning process of condenser coil, you need basic equipment like soft brush, grass shears, fin comb, coil cleaner, carpenter’s level and pry bar. On the other hand, for evaporator coils, keep these equipment handy like a stiff brush, screwdriver, household bleach and a large hand mirror.

Cleaning the Evaporator Coil
  • Start by removing the access plate which is situated behind the foil wrapped insulation. Use a screwdriver for the purpose.
  • Clean evaporator coils with the stiff brush. You can use the large hand mirror to see how much dust has gathered on evaporator coils.
  • Make sure to clean the tray placed below evaporator unit. Use the stiff brush for the purpose.
  • If you find it difficult to clean every part of the coil, then pull out the unit a bit to clean it properly.
  • Spread some household bleach into the tray weep holes. This prevents growth of fungus and mold.
  • Finally refit all parts of the entire unit into their appropriate places.

The good thing about evaporator coils is that these are not in direct contact with outside dirt. So, you need not follow a regular cleaning regime for evaporator coils. In case of condenser coil, the story is a bit different. Since these are placed externally i.e. in the outer portion of the air conditioner, you need to be more careful about condenser coil cleaning. Follow these steps.
  • First remove weeds, grasses or creepers that might have grown around the condenser unit.
  • Use a coil cleaner to clean condenser coils. You can opt for commercial coil cleaners which are readily available in the market.
  • Use a soft brush to clean the fins and remove accumulated dirt. A special tool called fin comb is available with which you can make the fins straight.
  • Check out whether the level of condenser unit is horizontal or not. Apply carpenter’s level to check the height of concrete pad on which the condenser is placed. Bring the condenser to horizontal level by using a shim and pry bar.
  • Now that you are done with the cleaning make sure that, all components of the condenser unit that you have taken out for cleaning are now refitted in their appropriate positions.

The above mentioned steps give a generic picture of how to clean air conditioner coils. For customized services and expert guidance, it is always advised that you get in touch with an HVAC expert.