There are several ways to calculate the HVAC savings from lower wattage lighting, but the simplest is a "rule of thumb" standard developed by ASHRAE (American Society of Heating, Refrigeration and Air Conditioning Engineers).Step 4. Add 380 Btu for each person who works in the space all day. If the number varies, take an average. Step 5. For each window in the space, add 1,000 Btu. For each kitchen, add 1,200 Btu. The result of this calculation gives you a rough idea of the minimum Btu of cooling capacity your air conditioner must have.

There are 12,000 Btu's per ton. The number 24 in the model number indicates the unit is 24,000 Btu's, divided by 12,000 Btu's per ton, equals 2 tons. 24,000 Btu's/12,000 Btu's per ton = 2 tons. Use the following conversion information to determine your existing system size (use the system model number NOT the serial number) 18 = 1.5 tons.

However, an HVAC company, like any business, is worth what a willing seller and a willing buyer, with no undue pressure on either party, are able to agree upon as the market value of the company. ... Using Rules-of-Thumb to Quickly Estimate Business Value.

Before one can design an efficient and effective air conditioning system, the load must first be calculated using established techniques. There are various methods in use. The most basic of these methods is a rule-of-thumb value -- for example, square feet of floor area per ton of cooling.

Divide the heat load by the cooling capacity of the air conditioning unit in BTU, to determine how many air conditioners are needed. Number of a/c units required = Total heat load BTU / Cooling capacity BTU On line heat gain calculator Manually calculating the size of air conditioner required can appear to be a complicated task.

• The measure of energy the HVAC system needs to add or remove from a space to provide the desired level of comfort - Btu/h • Not the . size. of the HVAC system - First piece of information needed - 12,000 Btu/h = 1 Ton Cooling • Can be. highly variable . What Is the Load?

As a general rule of thumb, a temperature between 70 and 80°F is a comfortable temperature for most people. For example, a house in Atlanta might want to determine the BTU usage during winter. Atlanta winters tend to hover around 45°F with chances to reach 30°F occasionally.

This calculator is provided for a quick and approximate check of heat loads. It should not be considered as a replacement for expert advice or a precise and detailed heat load calculation. It is advised to reconfirm with your air conditioner contractors again before you place your order.

Table of contents for HVAC equations, data, and rules of thumb / Arthur A. Bell, Jr. ... Theaters 5.25 Churches 5.26 Bowling Alleys 5.27 All Spaces 5.28 Cooling Load Calculation Procedure 5.29 Cooling Load Peak Time Estimate Part 6. Heating Load Rules of Thumb 6.01 All Buildings & Spaces 6.02 Buildings w/100% OA Systems 6.03 Bldg w/Heavy ...

Duct type: Metal Ductboard Flex Size by: Friction rate Velocity Friction Rate: per 100 ft. in/wg Duct TEL : ft. * include fittings in the Duct TEL

After going thru huge a stack of Manual J Load Calculations here is something I developed to get close to a load on a residence. This was developed from loads I have done in my area. After I get the job I do run a Manual J Load Calculation on the home. Cooling Load Best Construction - 700 Square Feet Per Ton. Average Construction - 600 Square Feet Per Ton.

As a rule of thumb, the majority of systems have a default friction rate of .05" wc, so you can use that average rate as your friction rate, calculate it using a ductulator chart, HVAC duct sizing software, or figure the friction rate yourself to get a more accurate measurement.

• Typical HVAC load design process • 1. Rough estimates of design loads & energy use • Such as by rules of thumb & floor areas • See "Cooling Load Check Figures" * • See references for some examples of databooks • 2. Develop & assess more info (design criteria, building info, system info) • Building layouts & plans are ...