Single Family Dwelling Load Calculation – Step by Step Example (Optional Method) CEC 220.82. (mercury) = 1 psi WORK = Force (energy exerted) X Distance • Divide the total by 1000 (of Btu/hr). Then calculate using formula A with the new specific heat from the point of change to the Step 2: • Calculate the maximum appliance input. 3160 Line Current (1 Phase) Amps = KW x 1000. 5 kW clothes dryer . Iron Sheath.S.) (Per 9.3.1.1, Exception 2, dryers are not included.) HVAC FORMULAS TON OF REFRIGERATION - The amount of heat required to melt a ton (2000 lbs.) This is the total heat loss at the outdoor design temp and the minimum output needed from the new furnace. Heat rejection as a function of the mass flow rate of … • Enter the input rating of all appliances in Table 1. Heating and Air-Conditioning (The Largest of the following shall be included): 1. Basic Air Conditioning Formulas TO DETERMINE COOLING Total Airflow Infiltration or Ventilation Number of Air Changes Per Hour – Total Number of Air Changes Per Hour – Outdoor Air Total Heat (HT) Sensible Heat (H S) Latent Heat (HL) Leaving Air D.B. 3 kW water heater . . Figure 54. Volts Line Current (3 Phase) Amps = KW x 1000. Volts x 1.73 Applied vs. To calculate wattage, use formula A for the heat needed to rise from initial to the point of change. The parameters involved in its calculation are shown below (from Steadman, 1979). SUB TOTAL HEAT LOSS 43,567 BTUh Heat Loss Factor Scaler Multiplier .10 x 1.74 = .17 x 43,567 = 7,406 BTUh 7. of ice at 32°F 288,000 BTU/24 hr. 4) Heat transfer for an internally reversible process: . . = ∫ . 5,000 Btu/h difference Location of the House. Rated KW Factors Rated Voltage Applied Voltage; 120 208 220 230 240 277 440 460 480; 120: 1.00: 3.00: 3.36: 3.67: 4.00: 5.33: Allowable Watt Density & Heater Selection - Air Heating Graph G-105S — Strip Heater Air Heating-Selection of Watt Density Graph G-106S — Finstrip® Heater Air Heating-Selection of Watt Density W/In 2 20 15 10 5 0 ABC Outlet Air Temperature (°F) 700 600 500 400 300 200 100 0 16 9 4 1 16 4 1.S.) Calculations for heating air in a duct Once the volume of air in standard cubic feet per minute (SCFM) and the required temperature rise in °F (ΔT) are known, the required kilowatt rating (KW) of the heater can be determined from the following formula: Heat rejection as a function of the mass flow rate of air, radiator borrowed from formula team..... 71 Figure 55. Water heater Space heater Range Other Total Total/1000 Step 2: • Calculate the total input of all appliances in the room. The Heat Index (or apparent temperature) is the result of extensive biometeorological studies. 3.412 x Heat-up Time (Hours) Formula C : *** The Specific Heat of a material changes at some temperature due to melting (fusion) or evaporation (vaporation). The sensible heat load comes from the following sources: 1. 2. Location of the House. calculation due to changing solar heat gains at various times of the day. 36,000 Btu/h. Heat conducted through the building (walls, ceiling, floor, windows). Each of these parameters can be described by an equation but they are given assumed magnitudes (in parentheses) in order to ... \WINDOWS\Desktop\heatindx.PDF Internal heat from … The total cooling or heating load of a building consists of two parts, the sensible heat, Qs , and the latent heat, Ql . 41,000 Btu/h. Convection: ̇= ℎ(. − ∞) Radiation: ̇= (. 4 −. Electric Heater Formulas Conversion 1 KW = 3413 BTU Load Requirement KW = CFM x Temp. Design Considerations: Best Case = East. APPROXIMATELY 2 inches in Hg. 2800 sq. Rise. 12,000 BTU/hr. ft. 14 kW range . Worst Case = North West. • Total the column. 1.5 kW dishwasher . Put your presentation title or confidentiality info here. Add Sub Total and Duct Loss to arrive at J: Total BTU/H Loss-Entire House. Heat Transfer and Work Relationships . Conduction: ̇= −. Temperature (T2) Enthalpy – Leaving Air (h 2) Leaving Air W.B.