HEAT TRANSFER SOLUTIONS INC. FORMULAS THERMODYNAICS OF AIR THERMODYNAMICS OF WATER q total = 4.5 x cfm x (h i – h f ) Btu/h q = 500 x gpm x (t i – t f ) Btu/h q sensible = 1.085 x cfm x (t i – t f ) Btu/h q = 450 x gpm x (t i – t f ) Btu/h (50% E.G.) q latent = 0.68 x cfm x (gr i – gr f ) Btu/h q = gpm x (t i -t f ) / 24 Tons Humidification = cfm x (gr i – gr f )/1,555 lb w /hr 1 psig = 2.31 ft. wg. 7000 gr = 1.0 lb w AIR SYSTEMS p total = p static + p velocity WATER SYSTEMS p velocity = (V/4005) 2 gpm 2 = gpm 1 (rpm 2 /rpm 1 ) cfm 1 / cfm 2 = rpm 1 / rpm 2 H 2 = H 1 (rpm 2 /rpm 1 ) 2 sp 1 / sp 2 = (cfm 1 / cfm 2 ) 2 BHP 2 = BHP 1 (rpm 2 /rpm 1 ) 3 bhp 1 / bhp 2 = (cfm 1 / cfm 2 ) 3 gpm 2 = gpm 1 (D 2 /D 1 ) Dp fittings = C o x (V/4005) 2 H 2 = H 1 (D 2 /D 1 ) 2 Fan bhp = cfm x SP (in. wg.) BHP 2 = BHP 1 (D 2 /D 1 ) 3 6356 x static efficiency Pump bhp = gpm x head (ft. wg.) BTUH = BHP x 2547/efficiency 3960 x pump efficiency Note: H = ft. head, D = impellor diameter POWER (WATTS) Single Phase = Volts x AMPs ELECTRICAL Three Phase = Volts x 1.732 x AMPs FLA = [(Motor AMPs) x (Motor Qty) + (Heater AMPs)] MCA – [(1.25) x (FLA)] MISCELLANEOUS MOP = [(2.25) x (1 st Motor AMPs) + (2 nd Motor AMPs) x 1.0 ton = 12,000 Btu/h (Heater AMPs)] COP = 3.516 / (kW/ton) EER = tons x 12 / (kW input) NOTE Btu/h = 3.412 x Watt t i = initial temperature, F, hp = kW x 1.3405 t f = final temperature, F 1 boiler hp = 33,480 Btu/hr h i = initial enthalpy Btu/lb a , 1 gallon = 8.33 lbs h f = final enthalpy, Btu/lb a gr = grains of water HEATER AMP CALCULATION v = air velocity, ft/min VOLTAGE AMPs per kW Formulas apply to air at 14.696 psi, 115/1 8.70 70F, 0.075 lb m /ft 3 120/1 8.33 208/1 4.81 230/1 4.35 240/1 4.17 277/1 3.61 208/3 2.78 230/3 2.51 240/3 2.41 460/3 1.26 480/3 1.20 575/3 1.00 600/3 .962

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HEAT TRANSFER SOLUTIONS INC.

FORMULAS

THERMODYNAICS OF AIR THERMODYNAMICS OF WATER qtotal = 4.5 x cfm x (hi – hf) Btu/h q = 500 x gpm x (ti – tf) Btu/h qsensible = 1.085 x cfm x (ti – tf) Btu/h q = 450 x gpm x (ti – tf) Btu/h (50% E.G.) qlatent = 0.68 x cfm x (gri – grf) Btu/h q = gpm x (ti-tf) / 24 Tons Humidification = cfm x (gri – grf)/1,555 lbw/hr 1 psig = 2.31 ft. wg. 7000 gr = 1.0 lbw AIR SYSTEMS ptotal = pstatic + pvelocity WATER SYSTEMS pvelocity = (V/4005)2 gpm2 = gpm1(rpm2/rpm1) cfm1 / cfm2 = rpm1 / rpm2 H2 = H1(rpm2/rpm1)2 sp1 / sp2 = (cfm1 / cfm2)

2 BHP2 = BHP1(rpm2/rpm1)3

bhp1 / bhp2 = (cfm1 / cfm2)3 gpm2 = gpm1(D2/D1)

Dpfittings = Co x (V/4005)2 H2 = H1(D2/D1)2

Fan bhp = cfm x SP (in. wg.) BHP2 = BHP1(D2/D1)3

6356 x static efficiency Pump bhp = gpm x head (ft. wg.) BTUH = BHP x 2547/efficiency 3960 x pump efficiency Note: H = ft. head, D = impellor diameter POWER (WATTS) Single Phase = Volts x AMPs ELECTRICAL Three Phase = Volts x 1.732 x AMPs FLA = [(Motor AMPs) x (Motor Qty) + (Heater AMPs)] MCA – [(1.25) x (FLA)] MISCELLANEOUS MOP = [(2.25) x (1st Motor AMPs) + (2nd Motor AMPs) x 1.0 ton = 12,000 Btu/h (Heater AMPs)] COP = 3.516 / (kW/ton) EER = tons x 12 / (kW input) NOTE Btu/h = 3.412 x Watt ti = initial temperature, �F, hp = kW x 1.3405 tf = final temperature, �F 1 boiler hp = 33,480 Btu/hr hi = initial enthalpy Btu/lba, 1 gallon = 8.33 lbs hf = final enthalpy, Btu/lba gr = grains of water HEATER AMP CALCULATION v = air velocity, ft/min VOLTAGE AMPs per kW Formulas apply to air at 14.696 psi, 115/1 8.70 70�F, 0.075 lbm/ft3 120/1 8.33 208/1 4.81 230/1 4.35 240/1 4.17 277/1 3.61 208/3 2.78 230/3 2.51 240/3 2.41 460/3 1.26 480/3 1.20 575/3 1.00 600/3 .962