X
treme Pumping
Cold Water Run System
The XTherm comes standard with a state-of-
the-art Cold Water Run system factory mounted
and plumbed. Raypak’s Cold Water Run system
provides
constant
protection
against
condensation in the primary heat exchanger.
The system utilizes a variable speed pump to
inject just the right amount of water from the
main system loop into the heater to maintain
the optimum inlet temperature. This allows the
full capacity of the heater to be utilized to meet
the system load, while at the same time
continuously maintaining the optimum inlet
water temperature to prevent condensation in
the primary heat exchanger. All of this keeps the
condensate were it belongs, in the stainless
steel secondary heat exchanger.
6
68%
78%
82%
97%
4,000,000
$80,653
$66,424
$62,047
$49,756
BTUH
Annual Fuel Usage
50 meters X 25 meters X 2 meters deep
Efficiencies
68%
78%
82%
97%
2,000,000
$26,243
$22,039
$20,712
$16,898
BTUH
Annual Fuel Usage
25 meters X 25 meters X 1-1/2 meters deep
Efficiencies
X
treme Pumping
The annual fuel usage is based on maintaining an indoor
swimming pool at 80ºF for 6 months of the year and using a
fuel cost of $1.00 per therm.
How to use the table below:
1. Select the desired temperature of the pool water.
2. Determine the mean (average) temperature of the month in which the pool will be
used.
3. Subtract the mean temperature from the desired swimming temperature. The
difference is the temperature rise.
4. Calculate the surface area of the pool in square feet.
5. Under the column headed by the temperature rise, determined in Step 3, find the
number closest to, but not less than, the pool surface area from Step 4. The left-hand
column will give you the correct model heater.
Sizing Formula
BTUH INPUT REQUIRED = (Pool Surface Area square feet) X (Temperature Rise) X (15)
This formula is based upon a 1º to 1-1/4º F temperature rise per hour and an average
3-1/2 MPH wind velocity.
Where high-wind conditions exist, select one size larger than determined by the
formula.
Rapid Heating
For 1-1/2ºF rise per hour: Increase BTUH input by 50%.
For 2ºF rise per hour: Increase BTUH input by 100%.
Always select a heater equal to or larger than the requirement. Over-sizing generally
reduces fuel costs.
Using one 2,000,000 BTUH Heater
Using two 2,000,000 BTUH Heater
6200.12-E_XTherm Brochure 8 page 3/29/11 10:59 AM Page 7
