Dictionary of Terms

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Dictionary of Terms

Air to Liquid

A heat transfer term referring to the transfer of heat from air to liquid or vice
versa.

Bypass Valve

A valve used to route water up to the PCS1 when heat is available in the
attic.

BTU

British Thermal Unit. The quantity of heat required to raise one pound of
water one degree Fahrenheit. A way to measure heat transfer.

BTU'S/HR

The hourly rate of BTU heat transfer. Calculated by the formula:
BTU'S per hour = ∆T x 8.34 x 60 x GPM

∆T

Symbol for temperature differential. Usually the output temperature minus
the input temperature. This can be either air or liquid temperatures. It can
also be the temperature difference between two heat containers. In our
material, it refers to the temperature difference between the output and the
input of the PCS1. This can be either the water temperature difference or
the air temperature difference. It also can be the difference between the
pool's water temperature and the attic temperature.

8.34

The weight of a gallon of water. A factor used in BTU calculations.

60

The minutes in an hour. A factor used in BTU calculations.

CFC

Chlorofluorocarbon chemicals found to damage the earth's protective ozone
layer. Found in swimming pool heat pumps.

Circuit

Refers to the heat transfer pipes that carry or are surrounded by
swimming pool water inside a heat exchanger.

Coil

Refers to the water coil used in the PCS1 which is used to transfer heat
from the attic air into the swimming pool's water.

Comfort Zone

The temperature at which water is the most comfortable for swimming.
That zone is from 80-84º F. Olympic and competitive pools maintain 78-80º
F.

Convection

A heat transfer principle where heat moves from one substance to another
by "convection". This usually means passive heat transfer. An example
would be an item physically sitting in a hot attic getting hot just from being
there.

C.O.P.

Coefficient of Performance. A term used primarily with heat pumps to rate
their performance against that of an electric resistance heater. C.O.P. is
calculated by the formula:

C.O.P. = BTUS OUT ÷ BTUS IN

Efficiency

Another term used with heat pumps to reflect how efficient heat pumps are
to an electric resistance heater. For example: a heat pump with a C.O.P.

Dictionary of Terms

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of 4 would be called 400% efficient. Able to deliver four times the energy
out than the amount used. Efficiency is calculated by the formula:
Efficiency = C.O.P. x 100%.

Flowreversal™ Valve

A valve used to reverse flow of water in a swimming pool so that the pool
will use heat efficiently. This means taking the water off the top of the pool
from the return lines and returning the water into the main drain at the
bottom of the pool. Flowreversal™ is a trademark of Innovative Pools &
Spa.

Forced Air

A heat transfer term referring to the use of an air moving device such as a
fan in conjunction with another device such as a water coil.

Forced Air Convection

The use of forced air to accelerate the heat transfer that would
normally occur passively by "convection".

Gallons/Cu Ft

Gallons per cubit foot. There are 7.5 gallons in the volume of one cubit
foot. Factor used in some pool heating calculations.

GPM

Gallons per minute. The flow rate of water in the swimming pool's support
system. A factor used in BTU calculations.

Heat Exchanger

A product that takes heat from one area and transfers it to another area. The
PCS1 transfers heat from the attic to the swimming pool.

Heat Pump

A method used to heat swimming pool's by using a reverse refrigeration
cycle. This method uses a compressor similar to the one in your
refrigerator. The product takes heat out of the ambient air to heat swimming
pools and is four times more efficient than using an electric resistance
heater.

KW

KW refers to Kilowatt and is a measurement of electricity equal to 1000
watts. One KW contains 3,412 BTUs of heat.

LX220/2Y

A temperature controller manufactured by Compool Corp.

PCS1

Acronym for "pool convection system one". Refers to the complete heat
exchange unit that is physically placed into the attic for heating swimming
pools.

PRO3 Valve

A bypass valve manufactured by Compool Corporation.

Proportioner Valve

A valve used in conjunction with a flowreversal valve so that proper
operation of the swimming pool's skimmers can be obtained during
reverse flow of water in the pool.

Dictionary of Terms

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Share-A-Heater™

A special valve manufactured by Mark Urban Products of Tustin, California
that allows a common heater to be shared by a pool and a spa. Share-A-
Heater™ is a Mark Urban Products.

Support System

Refers to the swimming pool equipment pad which usually is comprised of
the pool's pump, filter and other equipment used to run the pool.

Temperature Controller

An electronic device used to automate the bypass valve so that water is
automatically routed up to the PCS1 in the attic when heat is available.

Therm

One Therm equals 100,000 BTUs.

TmMr

A manual proportioner valve manufactured by Mark Urban Products of
Tustin, California.

Volume of Pool

Equal to the pools surface area times the average depth and is
expressed in cubit feet. Factor used in some pool heating calculations.

XmMr

A manual flowreversal valve manufactured by Mark Urban Products of
Tustin, California.