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Variable speed condensing furnace algorithm – Carrier 58MVP User Manual

Page 47

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A95094

VARIABLE SPEED CONDENSING FURNACE ALGORITHM

Using

re

corded Low Heat (LH)

and High Heat (H

H) val

u

es,

calcu

la

te

the

Heat

Lo

ad (HL)

usin

g:

HL=(228 X LH) + (350 X HH

)

Is HL

< 36

48

?

Is HL

> 56

00

?

Is 5

6

0

0

> HL

> 3

648

?

Calculate Low Heat (LH) on

time will be

16

m

inutes.

Calculate Low Heat (LH) on

time will be

0 minutes.

Unit will initiate the next cycle in

Lo

w Heat

for a

m

a

ximu

m

of

16

min. befor

e

initiati

ng High Heat if

th

e ca

ll f

o

r he

at st

ill e

xist

s.

Unit will initiate the next cycle

in High

Hea

t un

til the

th

ermo

stat

is satisfie

d.

Unit will iniate the next cycle in

Lo

w Heat

to

the

ne

arest m

inu

te

fo

r a p

e

ri

od

of

t

ime

as ca

lcul

at

e

d

by

the

following

:

LH

= (56

00 - HL

)/

122

The next cycle will be initiated

with

the calculat

ed Low

fire ru

n

time b

e

fo

re

initiat

in

g

h

igh

hea

t if

a

call for h

eat

is still

prese

n

t.

ru

n time

Is t

here

a ca

ll

fo

r he

at

?

The

Lo

w He

at and

High He

at

run

tim

e

s for

t

h

is cycle will be

as calculat

ed.

Ther

most

at is satisfied.

Ye

s

Ye

s

Ye

s

FEBRUARY 1995

47