70
Appendices
Reference Guide for Water Heating
= 23 gallons per hour
= 80otemp
= 45 gallons per hour
= 80otemp
ELECTRIC

Energy Costs:

KW x fuel costs = energy costs
100 x 0.05 = $5.00
To obtain gallons per hour
(GPH) recovery
WATTS
2.42 x (temp rise o F)
I have a 30-gallon electric
heater,non-simultaneous
operation,4,500 watt elements.
What is the recovery GPH if my
cold water is 40o F and my
thermostat is set to 120o F?
4,500
2.42 x 80
Temperature Rise (o F)
WATTS
2.42 x GPH
I have a 30-gallon electric
heater,non-simultaneous
operation,4,500 watt elements.
What is the maximum
temperature rise if the heater
can recover 23 gallons per hour?
4,500
2.42 x 23 rise
GAS

Energy Costs:

Cubic feet x fuel costs = energy costs
100 x 0.75 = $7.50
To obtain gallons per hour
(GPH) recovery
HOURLY INPUT (BTUs)
11.0 x (temp rise o F)
I have a 30-gallon gas heater,
rated at 40,000 BTUs.What is the
recovery GPH if my cold water is
40o F and my thermostat is set to
120o F?
40,000
11.0 x 80
Temperature Rise (o F)
HOURLY INPUT (BTUs)
11.0 x GPH
I have a 30-gallon gas heater,
rated at 40,000 BTUs.What is the
maximum temperature rise if the
heater can recover 45 gallons per
hour?
40,000
11.0 x 45 rise
GSW_ProdCatalog_Inside.qxd 3/7/08 1:52 PM Page 80