1 of 12 © 2009 A 268 - 03/09

- Application BrochureBoiler Control 268

A 26803/09

Features of the Boiler Control 268Please refer to Essay E 005: Control Functions and Benefits for a detailed description of these features.

ApplicationThe tekmar Boiler Control 268 can control the supply water temperature from up to 9 on / off stages based on outdoor temperature, control for Domestic Hot Water (DHW) generation, a setpoint requirement or optionally an external input signal (0 - 10 V (dc)). A large easy to read display provides current system tem-peratures and operating status. The control has outputs for a primary pump and either a combustion air damper or alarm. Based on the mode of operation selected, the control can operate different combinations of boiler stages and boiler pumps.

• Outdoor Reset• Characterized Heating Curve• Water Temperature Setback• Boost• Warm Weather Shut Down• Boiler Outdoor Reset• Boiler Differential (Automatic)• Boiler Minimum Supply• Boiler Post Purge• DHW Boiler Reset Override• DHW Condensing Boiler• DHW External Demand• DHW Post Purge

• DHW Priority• DHW Setback• PID Staging• Equal Run Time Rotation• Lo / Hi Fire Boiler Staging• Fixed Lead• Fixed Last• Fire Delay• Boiler Mass• Setpoint Boiler Reset Override• Setpoint Priority

115 V (ac)

24 V (ac)

AlarmBoiler Control 268Nine Stage Boiler & Setpoint

Menu Item

© 2009 A 268 - 03/09 2 of 12

Con

cept

Dra

win

gTh

is is

onl

y a

conc

ept d

raw

ing,

not

an

engi

neer

ed d

raw

ing.

It is

not

inte

nded

to

desc

ribe

a co

mpl

ete

syst

em,

nor

any

part

icul

ar s

yste

m.

It is

up

to t

he s

yste

m

desi

gner

to

dete

rmin

e th

e ne

cess

ary

com

pone

nts

for

and

conf

igur

atio

n of

the

pa

rtic

ular

sys

tem

bei

ng d

esig

ned,

inc

ludi

ng a

dditi

onal

equ

ipm

ent,

isol

atio

n re

lays

(fo

r lo

ads

grea

ter

than

the

con

trol’s

spe

cifie

d ou

tput

rat

ings

), an

d an

y sa

fety

dev

ices

whi

ch in

the

judg

emen

t of t

he d

esig

ner

are

appr

opria

te, i

n or

der

to p

rope

rly s

ize,

con

figur

e an

d de

sign

tha

t sy

stem

and

to

ensu

re c

ompl

ianc

e w

ith b

uild

ing

and

safe

ty c

ode

requ

irem

ents

.te

kmar

Con

trol S

yste

ms

Ltd.

, Can

ada;

tekm

ar C

ontro

l Sys

tem

s, In

c., U

.S.A

.; w

ww

.tekm

arco

ntro

ls.c

omH

ead

Off

ice:

510

0 S

ilver

Sta

r R

oad,

Ver

non,

B.C

. Can

ada,

V1B

3K

4; (2

50) 5

45-7

749

Fax

(250

) 545

-065

0

- App

licat

ion

Mec

hani

cal

Sys

tem

Ope

ratio

nTh

e B

oile

r Con

trol 2

68 p

rovi

des

outd

oor r

eset

to a

spa

ce h

eatin

g sy

stem

. The

268

pro

vide

s st

agin

g an

d ro

tatio

n fo

r thr

ee

two-

stag

e bo

ilers

. The

boi

lers

are

pip

ed p

aral

lel p

rimar

y-se

cond

ary

and

the

indi

vidu

al b

oile

r pum

ps a

re c

ontro

lled

by th

e 26

8 to

allo

w fo

r po

st p

urgi

ng o

f the

boi

lers

afte

r th

ey h

ave

shut

off.

The

268

has

an

alar

m c

onta

ct th

at c

lose

s du

ring

an

erro

r mes

sage

.

A1 =

Ala

rmP

1 =

Prim

ary

Sys

tem

Pum

pP

2...P

4 =

Boi

ler P

ump

S1

= B

oile

r Sup

ply

Sen

sor 0

82S

2 =

Out

door

Sen

sor 0

70V

1 =

Bal

anci

ng o

r Pre

ssur

e B

ypas

s V

alve

A 2

68-1

03/0

9

P4

P3

P2Out

door

Sen

sor

(S2)

070

115

V (a

c)24

V (a

c)

Cla

ss 2

Tran

sfor

mer

268 P1

ΔP

V1

TT

T

Boi

ler S

uppl

y S

enso

r(S

1) 0

82

Ala

rm (A

1)

3 of 12 © 2009 A 268 - 03/09

Con

cept

Dra

win

gTh

is is

onl

y a

conc

ept d

raw

ing,

not

an

engi

neer

ed d

raw

ing.

It is

not

inte

nded

to

desc

ribe

a co

mpl

ete

syst

em,

nor

any

part

icul

ar s

yste

m.

It is

up

to t

he s

yste

m

desi

gner

to

dete

rmin

e th

e ne

cess

ary

com

pone

nts

for

and

conf

igur

atio

n of

the

pa

rtic

ular

sys

tem

bei

ng d

esig

ned,

inc

ludi

ng a

dditi

onal

equ

ipm

ent,

isol

atio

n re

lays

(fo

r lo

ads

grea

ter

than

the

con

trol’s

spe

cifie

d ou

tput

rat

ings

), an

d an

y sa

fety

dev

ices

whi

ch in

the

judg

emen

t of t

he d

esig

ner

are

appr

opria

te, i

n or

der

to p

rope

rly s

ize,

con

figur

e an

d de

sign

tha

t sy

stem

and

to

ensu

re c

ompl

ianc

e w

ith b

uild

ing

and

safe

ty c

ode

requ

irem

ents

.te

kmar

Con

trol S

yste

ms

Ltd.

, Can

ada;

tekm

ar C

ontro

l Sys

tem

s, In

c., U

.S.A

.; w

ww

.tekm

arco

ntro

ls.c

omH

ead

Off

ice:

510

0 S

ilver

Sta

r R

oad,

Ver

non,

B.C

. Can

ada,

V1B

3K

4; (2

50) 5

45-7

749

Fax

(250

) 545

-065

0

- App

licat

ion

Ele

ctri

cal

requ

ired

optio

nal

Ess

entia

l Con

trol

Set

tings

MO

DE

= 4

DH

W M

OD

E =

OFF

A 2

68-1

03/0

9

A1 =

Ala

rmP

1 =

Prim

ary

Sys

tem

Pum

pP

2...P

4 =

Boi

ler P

ump

S1

= B

oile

r Sup

ply

Sen

sor 0

82S

2 =

Out

door

Sen

sor 0

70

Boi

ler #

1Lo

Hi

Boi

ler #

2Lo

Hi

Boi

ler #

3Lo

Hi

C24

V (a

c)R

N11

5 V

(ac)

Cla

ss 2

Tran

sfor

mer

L

S1 S

2

P1

P2

P3

P4

A1

Do

not a

pply

pow

er

1 Com

2 Boil

Sup

3 Boil

Ret

4 Out

5 UnO

Sw

6 Boil

Dem

7 Com

Dem

8 Setp

/DH

W

9 Powe

rN

LPr

im P1

12 C.A.

/Al

arm

DHW

1314 Re

lay

1

1510

11

1

16 Rela

y2

17 2

18 Rela

y3

19 3

20 Rela

y4

21 4

22 Rela

y5

23 5

24 Rela

y6

25 6

26 Rela

y7

27 7

28 Rela

y8

29 8

30 Rela

y 9/31

268

5A5A

5A5A

5A5A

5A5A

5A5A

5A

+-

© 2009 A 268 - 03/09 4 of 12

Con

cept

Dra

win

gTh

is is

onl

y a

conc

ept d

raw

ing,

not

an

engi

neer

ed d

raw

ing.

It is

not

inte

nded

to

desc

ribe

a co

mpl

ete

syst

em,

nor

any

part

icul

ar s

yste

m.

It is

up

to t

he s

yste

m

desi

gner

to

dete

rmin

e th

e ne

cess

ary

com

pone

nts

for

and

conf

igur

atio

n of

the

pa

rtic

ular

sys

tem

bei

ng d

esig

ned,

inc

ludi

ng a

dditi

onal

equ

ipm

ent,

isol

atio

n re

lays

(fo

r lo

ads

grea

ter

than

the

con

trol’s

spe

cifie

d ou

tput

rat

ings

), an

d an

y sa

fety

dev

ices

whi

ch in

the

judg

emen

t of t

he d

esig

ner

are

appr

opria

te, i

n or

der

to p

rope

rly s

ize,

con

figur

e an

d de

sign

tha

t sy

stem

and

to

ensu

re c

ompl

ianc

e w

ith b

uild

ing

and

safe

ty c

ode

requ

irem

ents

.te

kmar

Con

trol S

yste

ms

Ltd.

, Can

ada;

tekm

ar C

ontro

l Sys

tem

s, In

c., U

.S.A

.; w

ww

.tekm

arco

ntro

ls.c

omH

ead

Off

ice:

510

0 S

ilver

Sta

r R

oad,

Ver

non,

B.C

. Can

ada,

V1B

3K

4; (2

50) 5

45-7

749

Fax

(250

) 545

-065

0

- App

licat

ion

Mec

hani

cal

A 2

68-2

03/0

9

Sys

tem

Ope

ratio

nTh

e B

oile

r C

ontro

l 26

8 pr

ovid

es o

utdo

or r

eset

to

a sp

ace

heat

ing

syst

em a

nd s

etpo

int

oper

atio

n fo

r a

spa.

The

268

pr

ovid

es s

tagi

ng a

nd ro

tatio

n fo

r thr

ee th

ree-

stag

e bo

ilers

. The

boi

lers

are

pip

ed in

reve

rse

retu

rn w

ith a

sin

gle

pum

p. T

he

spa

is p

iped

in p

rimar

y-se

cond

ary

to th

e bo

ilers

. The

spa

ce h

eatin

g zo

nes

are

pipe

d in

prim

ary-

seco

ndar

y to

the

boile

rs.

The

268

has

an a

larm

con

tact

that

clo

ses

durin

g an

err

or m

essa

ge.

Out

door

Sen

sor

(S2)

070

150

115

V (a

c)24

V (a

c)

Cla

ss 2

Tran

sfor

mer

268

P3

R2

Z1Z2

Z3P

1Δ

P

V3

R1

V2

P2

V1

MM

M

Boi

ler S

uppl

y S

enso

r(S

1) 0

82

Spa

Sen

sor

(S3)

071

Ala

rm (A

1)

A1 =

Ala

rmP

1 =

Prim

ary

Pum

pP

2 =

Spa

Pum

pP

3 =

Sys

tem

Pum

pR

1, R

2 =

Rel

ay 0

03S

1 =

Boi

ler S

uppl

y S

enso

r 082

S2

= O

utdo

or S

enso

r 070

S3

= S

pa S

enso

r 071

V1,

V2

= B

alan

cing

Val

ve o

r Glo

be V

alve

V3

= P

ress

ure

Diff

eren

tial B

ypas

s V

alve

Z1, .

..Z3

= Z

one

Val

ve

5 of 12 © 2009 A 268 - 03/09

Con

cept

Dra

win

gTh

is is

onl

y a

conc

ept d

raw

ing,

not

an

engi

neer

ed d

raw

ing.

It is

not

inte

nded

to

desc

ribe

a co

mpl

ete

syst

em,

nor

any

part

icul

ar s

yste

m.

It is

up

to t

he s

yste

m

desi

gner

to

dete

rmin

e th

e ne

cess

ary

com

pone

nts

for

and

conf

igur

atio

n of

the

pa

rtic

ular

sys

tem

bei

ng d

esig

ned,

inc

ludi

ng a

dditi

onal

equ

ipm

ent,

isol

atio

n re

lays

(fo

r lo

ads

grea

ter

than

the

con

trol’s

spe

cifie

d ou

tput

rat

ings

), an

d an

y sa

fety

dev

ices

whi

ch in

the

judg

emen

t of t

he d

esig

ner

are

appr

opria

te, i

n or

der

to p

rope

rly s

ize,

con

figur

e an

d de

sign

tha

t sy

stem

and

to

ensu

re c

ompl

ianc

e w

ith b

uild

ing

and

safe

ty c

ode

requ

irem

ents

.te

kmar

Con

trol S

yste

ms

Ltd.

, Can

ada;

tekm

ar C

ontro

l Sys

tem

s, In

c., U

.S.A

.; w

ww

.tekm

arco

ntro

ls.c

omH

ead

Off

ice:

510

0 S

ilver

Sta

r R

oad,

Ver

non,

B.C

. Can

ada,

V1B

3K

4; (2

50) 5

45-7

749

Fax

(250

) 545

-065

0

- App

licat

ion

Ele

ctri

cal

requ

ired

optio

nal

Ess

entia

l Con

trol

Set

tings

MO

DE

= 5

Set

poin

t MO

DE

= 3

A 2

68-2

03/0

9

A1 =

Ala

rmP

1 =

Prim

ary

Pum

pP

2 =

Spa

Pum

pP

3 =

Sys

tem

Pum

pR

1, R

2 =

Rel

ay 0

03S

1 =

Boi

ler S

uppl

y S

enso

r 082

S2

= O

utdo

or S

enso

r 070

S3

= S

pa S

enso

r 071

Z1, .

..Z3

= Z

one

Val

ve

S3

C24

V (a

c)R

N11

5 V

(ac)

Cla

ss 2

Tran

sfor

mer

L

S1 S

2

P1

A1

P2

R1

R2

Z1...

Z3

Do

not a

pply

pow

er

1 Com

2 Boil

Sup

3 Boil

Ret

4 Out

5 UnO

Sw

6 Boil

Dem

7 Com

Dem

8 Setp

/DH

W

9 Powe

rN

LPr

im P1

12 C.A.

/Al

arm

DHW

1314 Re

lay

1

1510

11

1

16 Rela

y2

17 2

18 Rela

y3

19 3

20 Rela

y4

21 4

22 Rela

y5

23 5

24 Rela

y6

25 6

26 Rela

y7

27 7

28 Rela

y8

29 8

30 Rela

y 9/31

268

5A5A

5A5A

5A5A

5A5A

5A5A

5A

+-

7 8 1 2

6 5 4 3

P3

7 8 1 2

6 5 4 3

Boi

ler #

1

LoM

edH

iB

oile

r #2

LoM

edH

i

Boi

ler #

3

LoM

edH

i

C-

8A8A

No

Pow

er

R+Co

mN/

ON/

C

12

34

56

7

Sens

orPo

wer

150

OnPWM

Off

© 2009 A 268 - 03/09 6 of 12

Con

cept

Dra

win

gTh

is is

onl

y a

conc

ept d

raw

ing,

not

an

engi

neer

ed d

raw

ing.

It is

not

inte

nded

to

desc

ribe

a co

mpl

ete

syst

em,

nor

any

part

icul

ar s

yste

m.

It is

up

to t

he s

yste

m

desi

gner

to

dete

rmin

e th

e ne

cess

ary

com

pone

nts

for

and

conf

igur

atio

n of

the

pa

rtic

ular

sys

tem

bei

ng d

esig

ned,

inc

ludi

ng a

dditi

onal

equ

ipm

ent,

isol

atio

n re

lays

(fo

r lo

ads

grea

ter

than

the

con

trol’s

spe

cifie

d ou

tput

rat

ings

), an

d an

y sa

fety

dev

ices

whi

ch in

the

judg

emen

t of t

he d

esig

ner

are

appr

opria

te, i

n or

der

to p

rope

rly s

ize,

con

figur

e an

d de

sign

tha

t sy

stem

and

to

ensu

re c

ompl

ianc

e w

ith b

uild

ing

and

safe

ty c

ode

requ

irem

ents

.te

kmar

Con

trol S

yste

ms

Ltd.

, Can

ada;

tekm

ar C

ontro

l Sys

tem

s, In

c., U

.S.A

.; w

ww

.tekm

arco

ntro

ls.c

omH

ead

Off

ice:

510

0 S

ilver

Sta

r R

oad,

Ver

non,

B.C

. Can

ada,

V1B

3K

4; (2

50) 5

45-7

749

Fax

(250

) 545

-065

0

- App

licat

ion

Mec

hani

cal

A 2

68-3

03/0

9

Sys

tem

Ope

ratio

nTh

e B

oile

r C

ontro

l 268

pro

vide

s D

HW

ope

ratio

n to

a s

ingl

e do

mes

tic h

ot w

ater

sto

rage

tank

. The

268

pro

vide

s st

agin

g,

rota

tion

and

purg

ing

to fo

ur tw

o-st

age

boile

rs. T

he b

oile

rs a

re p

iped

in re

vers

e re

turn

with

a s

ingl

e pu

mp.

A c

ombu

stio

n ai

r dam

per i

s al

so c

ontro

lled

by th

e 26

8.

A1 =

DH

W A

quas

tat

C1

= C

ombu

stio

n A

ir D

ampe

rP

1 =

Prim

ary

Sys

tem

Pum

pS

1 =

Boi

ler S

uppl

y S

enso

r 082

S2

= O

utdo

or S

enso

r 070

MC

ombu

stio

nA

ir D

ampe

r (C

1)O

utdo

or S

enso

r(S

2) 0

70

115

V (a

c)24

V (a

c)

Cla

ss 2

Tran

sfor

mer

P1

A1

268

Boi

ler S

uppl

y S

enso

r(S

1) 0

82

7 of 12 © 2009 A 268 - 03/09

Con

cept

Dra

win

gTh

is is

onl

y a

conc

ept d

raw

ing,

not

an

engi

neer

ed d

raw

ing.

It is

not

inte

nded

to

desc

ribe

a co

mpl

ete

syst

em,

nor

any

part

icul

ar s

yste

m.

It is

up

to t

he s

yste

m

desi

gner

to

dete

rmin

e th

e ne

cess

ary

com

pone

nts

for

and

conf

igur

atio

n of

the

pa

rtic

ular

sys

tem

bei

ng d

esig

ned,

inc

ludi

ng a

dditi

onal

equ

ipm

ent,

isol

atio

n re

lays

(fo

r lo

ads

grea

ter

than

the

con

trol’s

spe

cifie

d ou

tput

rat

ings

), an

d an

y sa

fety

dev

ices

whi

ch in

the

judg

emen

t of t

he d

esig

ner

are

appr

opria

te, i

n or

der

to p

rope

rly s

ize,

con

figur

e an

d de

sign

tha

t sy

stem

and

to

ensu

re c

ompl

ianc

e w

ith b

uild

ing

and

safe

ty c

ode

requ

irem

ents

.te

kmar

Con

trol S

yste

ms

Ltd.

, Can

ada;

tekm

ar C

ontro

l Sys

tem

s, In

c., U

.S.A

.; w

ww

.tekm

arco

ntro

ls.c

omH

ead

Off

ice:

510

0 S

ilver

Sta

r R

oad,

Ver

non,

B.C

. Can

ada,

V1B

3K

4; (2

50) 5

45-7

749

Fax

(250

) 545

-065

0

- App

licat

ion

Ele

ctri

cal

requ

ired

optio

nal

Ess

entia

l Con

trol

Set

tings

MO

DE

= 3

DH

W M

OD

E =

1

A 2

68-3

03/0

9

A1 =

DH

W A

quas

tat

C1

= C

ombu

stio

n A

ir D

ampe

rP

1 =

Prim

ary

Sys

tem

Pum

pS

1 =

Boi

ler S

uppl

y S

enso

r 082

S2

= O

utdo

or S

enso

r 070

C24

V (a

c)R

N11

5 V

(ac)

Cla

ss 2

Tran

sfor

mer

L

S1 S

2

P1

Do

not a

pply

pow

er

1 Com

2 Boil

Sup

3 Boil

Ret

4 Out

5 UnO

Sw

6 Boil

Dem

7 Com

Dem

8 Setp

/DH

W

9 Powe

rN

LPr

im P1

12 C.A.

/Al

arm

DHW

1314 Re

lay

1

1510

11

1

16 Rela

y2

17 2

18 Rela

y3

19 3

20 Rela

y4

21 4

22 Rela

y5

23 5

24 Rela

y6

25 6

26 Rela

y7

27 7

28 Rela

y8

29 8

30 Rela

y 9/31

268

5A5A

5A5A

5A5A

5A5A

5A5A

5A

+-

MC

1A

1

Boi

ler #

1Lo

Hi

Boi

ler #

3Lo

Hi

Boi

ler #

2Lo

Hi

Boi

ler #

4Lo

Hi

© 2009 A 268 - 03/09 8 of 12

Con

cept

Dra

win

gTh

is is

onl

y a

conc

ept d

raw

ing,

not

an

engi

neer

ed d

raw

ing.

It is

not

inte

nded

to

desc

ribe

a co

mpl

ete

syst

em,

nor

any

part

icul

ar s

yste

m.

It is

up

to t

he s

yste

m

desi

gner

to

dete

rmin

e th

e ne

cess

ary

com

pone

nts

for

and

conf

igur

atio

n of

the

pa

rtic

ular

sys

tem

bei

ng d

esig

ned,

inc

ludi

ng a

dditi

onal

equ

ipm

ent,

isol

atio

n re

lays

(fo

r lo

ads

grea

ter

than

the

con

trol’s

spe

cifie

d ou

tput

rat

ings

), an

d an

y sa

fety

dev

ices

whi

ch in

the

judg

emen

t of t

he d

esig

ner

are

appr

opria

te, i

n or

der

to p

rope

rly s

ize,

con

figur

e an

d de

sign

tha

t sy

stem

and

to

ensu

re c

ompl

ianc

e w

ith b

uild

ing

and

safe

ty c

ode

requ

irem

ents

.te

kmar

Con

trol S

yste

ms

Ltd.

, Can

ada;

tekm

ar C

ontro

l Sys

tem

s, In

c., U

.S.A

.; w

ww

.tekm

arco

ntro

ls.c

omH

ead

Off

ice:

510

0 S

ilver

Sta

r R

oad,

Ver

non,

B.C

. Can

ada,

V1B

3K

4; (2

50) 5

45-7

749

Fax

(250

) 545

-065

0

- App

licat

ion

Mec

hani

cal

A 2

68-4

03/0

9

A1 =

DH

W A

quas

tat

C1

= C

ombu

stio

n A

ir D

ampe

rP

1 =

Prim

ary

Sys

tem

Pum

pP

2...P

5 =

Boi

ler P

ump

P6

= D

HW

Pum

pS

1 =

Boi

ler S

uppl

y S

enso

r 082

S2

= B

oile

r Ret

urn

Sen

sor 0

82

Sys

tem

Ope

ratio

nTh

e B

oile

r C

ontro

l 268

acc

epts

a 0

- 1

0 V

(dc

) si

gnal

fro

m a

n E

nerg

y M

anag

emen

t S

yste

m t

o su

pply

hea

t to

a s

pace

he

atin

g sy

stem

. The

268

ope

rate

s an

indi

rect

dom

estic

hot

wat

er ta

nk b

ased

upo

n a

dem

and

from

the

tank

aqu

asta

t. Th

e 26

8 pr

ovid

es s

tagi

ng a

nd ro

tatio

n fo

r up

to fo

ur s

ingl

e st

age

boile

rs. T

he b

oile

rs a

re p

iped

in p

aral

lel p

rimar

y-se

cond

ary

and

the

boile

r pum

ps a

re c

ontro

lled

by th

e 26

8 to

allo

w fo

r pos

t pur

ging

of t

he b

oile

rs a

fter t

hey

have

shu

t off.

A c

ombu

stio

n ai

r da

mpe

r is

also

con

trolle

d by

the

268.

P3

P4

P5

P2

MC

ombu

stio

nA

ir D

ampe

r (C

1)

268

P1

A1

P6

DH

WTa

nk

115

V (a

c)

Ana

log

Inpu

t fro

m E

MS

24 V

(ac)

Cla

ss 2

Tran

sfor

mer

Boi

ler S

uppl

y S

enso

r(S

1) 0

82

Boi

ler R

etur

n S

enso

r(S

2) 0

82

9 of 12 © 2009 A 268 - 03/09

Con

cept

Dra

win

gTh

is is

onl

y a

conc

ept d

raw

ing,

not

an

engi

neer

ed d

raw

ing.

It is

not

inte

nded

to

desc

ribe

a co

mpl

ete

syst

em,

nor

any

part

icul

ar s

yste

m.

It is

up

to t

he s

yste

m

desi

gner

to

dete

rmin

e th

e ne

cess

ary

com

pone

nts

for

and

conf

igur

atio

n of

the

pa

rtic

ular

sys

tem

bei

ng d

esig

ned,

inc

ludi

ng a

dditi

onal

equ

ipm

ent,

isol

atio

n re

lays

(fo

r lo

ads

grea

ter

than

the

con

trol’s

spe

cifie

d ou

tput

rat

ings

), an

d an

y sa

fety

dev

ices

whi

ch in

the

judg

emen

t of t

he d

esig

ner

are

appr

opria

te, i

n or

der

to p

rope

rly s

ize,

con

figur

e an

d de

sign

tha

t sy

stem

and

to

ensu

re c

ompl

ianc

e w

ith b

uild

ing

and

safe

ty c

ode

requ

irem

ents

.te

kmar

Con

trol S

yste

ms

Ltd.

, Can

ada;

tekm

ar C

ontro

l Sys

tem

s, In

c., U

.S.A

.; w

ww

.tekm

arco

ntro

ls.c

omH

ead

Off

ice:

510

0 S

ilver

Sta

r R

oad,

Ver

non,

B.C

. Can

ada,

V1B

3K

4; (2

50) 5

45-7

749

Fax

(250

) 545

-065

0

- App

licat

ion

Ele

ctri

cal

requ

ired

optio

nal

A 2

68-4

03/0

9

Ess

entia

l Con

trol

Set

tings

MO

DE

= 2

DH

W M

OD

E =

1 (n

o pr

iorit

y)

2 (w

ith p

riorit

y)

A1 =

DH

W A

quas

tat

C1

= C

ombu

stio

n A

ir D

ampe

rP

1 =

Prim

ary

Sys

tem

Pum

pP

2...P

5 =

Boi

ler P

ump

P6

= D

HW

Pum

pS

1 =

Boi

ler S

uppl

y S

enso

r 082

S2

= B

oile

r Ret

urn

Sen

sor 0

82

C24

V (a

c)R

N11

5 V

(ac)

Cla

ss 2

Tran

sfor

mer

L

S1 S2

500W

0-20

mA

or 0

-10

V (d

c)

P4

P3

P2

P1

P5

P6

Do

not a

pply

pow

er

1 Com

2 Boil

Sup

3 Boil

Ret

4 Out

5 UnO

Sw

6 Boil

Dem

7 Com

Dem

8 Setp

/DH

W

9 Powe

rN

LPr

im P1

12 C.A.

/Al

arm

DHW

1314 Re

lay

1

1510

11

1

16 Rela

y2

17 2

18 Rela

y3

19 3

20 Rela

y4

21 4

22 Rela

y5

23 5

24 Rela

y6

25 6

26 Rela

y7

27 7

28 Rela

y8

29 8

30 Rela

y 9/31

268

5A5A

5A5A

5A5A

5A5A

5A5A

5A

+-

MC

1A

1

Boi

ler

#1B

oile

r#2

Boi

ler

#3B

oile

r#4

© 2009 A 268 - 03/09 10 of 12

Con

cept

Dra

win

gTh

is is

onl

y a

conc

ept d

raw

ing,

not

an

engi

neer

ed d

raw

ing.

It is

not

inte

nded

to

desc

ribe

a co

mpl

ete

syst

em,

nor

any

part

icul

ar s

yste

m.

It is

up

to t

he s

yste

m

desi

gner

to

dete

rmin

e th

e ne

cess

ary

com

pone

nts

for

and

conf

igur

atio

n of

the

pa

rtic

ular

sys

tem

bei

ng d

esig

ned,

inc

ludi

ng a

dditi

onal

equ

ipm

ent,

isol

atio

n re

lays

(fo

r lo

ads

grea

ter

than

the

con

trol’s

spe

cifie

d ou

tput

rat

ings

), an

d an

y sa

fety

dev

ices

whi

ch in

the

judg

emen

t of t

he d

esig

ner

are

appr

opria

te, i

n or

der

to p

rope

rly s

ize,

con

figur

e an

d de

sign

tha

t sy

stem

and

to

ensu

re c

ompl

ianc

e w

ith b

uild

ing

and

safe

ty c

ode

requ

irem

ents

.te

kmar

Con

trol S

yste

ms

Ltd.

, Can

ada;

tekm

ar C

ontro

l Sys

tem

s, In

c., U

.S.A

.; w

ww

.tekm

arco

ntro

ls.c

omH

ead

Off

ice:

510

0 S

ilver

Sta

r R

oad,

Ver

non,

B.C

. Can

ada,

V1B

3K

4; (2

50) 5

45-7

749

Fax

(250

) 545

-065

0

- App

licat

ion

Mec

hani

cal

A 2

68-5

03/0

9

A1 =

DH

W A

quas

tat

A2

= A

larm

P1

= P

rimar

y P

ump

P2

= D

HW

Pum

pP

3 =

Sys

tem

Pum

pR

1, R

2 =

Rel

ay 0

03S

1 =

Boi

ler S

uppl

y S

enso

r 082

S2

= O

utdo

or S

enso

r 070

Z1...

Z3

= Z

one

Val

ve

Sys

tem

Ope

ratio

nTh

e B

oile

r C

ontro

l 268

pro

vide

s ou

tdoo

r re

set

to a

spa

ce h

eatin

g sy

stem

and

dom

estic

hot

wat

er o

pera

tion.

The

268

pr

ovid

es s

tagi

ng a

nd r

otat

ion

for

four

two-

stag

e bo

ilers

. The

boi

lers

are

pip

ed in

rev

erse

ret

urn

with

a s

ingl

e pu

mp.

The

sp

ace

heat

ing

zone

s ar

e pi

ped

in p

rimar

y-se

cond

ary

to t

he b

oile

rs.

The

dom

estic

hot

wat

er t

ank

is p

iped

in p

rimar

y-se

cond

ary

to t

he b

oile

rs a

nd h

as a

n ex

tern

al r

elay

to

prov

ide

prio

rity

over

the

hea

ting

syst

em.

The

268

has

an a

larm

co

ntac

t tha

t clo

ses

durin

g an

err

or m

essa

ge.

Out

door

Sen

sor

(S2)

070

115

V (a

c)24

V (a

c)

Cla

ss 2

Tran

sfor

mer

P1

268

P3

P2

R2

R1

A1

Z1Z2

Z3

DH

WTa

nk

tekm

ar 5

00 s

erie

s th

erm

osta

ts

MM

M

Boi

ler S

uppl

y S

enso

r(S

1) 0

82

Ala

rm (A

2)

11 of 12 © 2009 A 268 - 03/09

Con

cept

Dra

win

gTh

is is

onl

y a

conc

ept d

raw

ing,

not

an

engi

neer

ed d

raw

ing.

It is

not

inte

nded

to

desc

ribe

a co

mpl

ete

syst

em,

nor

any

part

icul

ar s

yste

m.

It is

up

to t

he s

yste

m

desi

gner

to

dete

rmin

e th

e ne

cess

ary

com

pone

nts

for

and

conf

igur

atio

n of

the

pa

rtic

ular

sys

tem

bei

ng d

esig

ned,

inc

ludi

ng a

dditi

onal

equ

ipm

ent,

isol

atio

n re

lays

(fo

r lo

ads

grea

ter

than

the

con

trol’s

spe

cifie

d ou

tput

rat

ings

), an

d an

y sa

fety

dev

ices

whi

ch in

the

judg

emen

t of t

he d

esig

ner

are

appr

opria

te, i

n or

der

to p

rope

rly s

ize,

con

figur

e an

d de

sign

tha

t sy

stem

and

to

ensu

re c

ompl

ianc

e w

ith b

uild

ing

and

safe

ty c

ode

requ

irem

ents

.te

kmar

Con

trol S

yste

ms

Ltd.

, Can

ada;

tekm

ar C

ontro

l Sys

tem

s, In

c., U

.S.A

.; w

ww

.tekm

arco

ntro

ls.c

omH

ead

Off

ice:

510

0 S

ilver

Sta

r R

oad,

Ver

non,

B.C

. Can

ada,

V1B

3K

4; (2

50) 5

45-7

749

Fax

(250

) 545

-065

0

- App

licat

ion

Ele

ctri

cal

requ

ired

optio

nal

Ess

entia

l Con

trol

Set

tings

MO

DE

= 3

DH

W M

OD

E =

4 (w

ith p

riorit

y)

A 2

68-5

03/0

9

A1 =

DH

W A

quas

tat

A2

= A

larm

P1

= P

rimar

y P

ump

P2

= D

HW

Pum

pP

3 =

Sys

tem

Pum

pR

1, R

2 =

Rel

ay 0

03S

1 =

Boi

ler S

uppl

y S

enso

r 082

S2

= O

utdo

or S

enso

r 070

Z1...

Z3

= Z

one

Val

ve

C24

V (a

c)R

N11

5 V

(ac)

Cla

ss 2

Tran

sfor

mer

L

A1

R2

R1

P1

P2

P3

Z3

M

R

tekm

ar 5

00 S

erie

sTh

erm

osta

ts

CRe

lay

1R

tekm

ar 5

00 S

erie

sTh

erm

osta

ts

CRe

lay

1 Z2

M

R

tekm

ar 5

00 S

erie

sTh

erm

osta

ts

CRe

lay

1 Z1

M

7 8 1 2

6 5 4 3

Do

not a

pply

pow

er

1 Com

2 Boil

Sup

3 Boil

Ret

4 Out

5 UnO

Sw

6 Boil

Dem

7 Com

Dem

8 Setp

/DH

W

9 Powe

rN

LPr

im P1

12 C.A.

/Al

arm

DHW

1314 Re

lay

1

1510

11

1

16 Rela

y2

17 2

18 Rela

y3

19 3

20 Rela

y4

21 4

22 Rela

y5

23 5

24 Rela

y6

25 6

26 Rela

y7

27 7

28 Rela

y8

29 8

30 Rela

y 9/31

268

5A5A

5A5A

5A5A

5A5A

5A5A

5A

+-

2 1 8 7

3 4 5 6

A2

S1 S

2

Boi

ler #

2Lo

Hi

Boi

ler #

1Lo

Hi

Boi

ler #

4Lo

Hi

Boi

ler #

3Lo

Hi

Product design, software and literature are Copyright © 2009 by:tekmar Control Systems Ltd. and tekmar Control Systems, Inc.

All specifications are subject to change without notice.Printed in Canada. A 268 - 03/09. 12 of 12

Specifi cations

tekmar Control Systems Ltd., Canadatekmar Control Systems, Inc., U.S.A.Head Office: 5100 Silver Star RoadVernon, B.C. Canada V1B 3K4(250) 545-7749 Fax. (250) 545-0650Web Site: www.tekmarcontrols.com

The following are the recommended specifications for the Boiler Control 268

• The control shall be able to operate up to a total of 9 on / off stages.

• The control shall be able to operate boilers that have one, two, three or four independent on / off stages.

• The control shall have the ability to calculate the boilers’ target temperature based on outdoor reset.

• The control shall have the ability to have the boilers’ target temperature set using an adjustable setpoint.

• The control shall have an adjustable warm weather shut down. The warm weather shut down only applies to outdoor reset operation.

• The control shall have a primary pump contact that operates during a call for space heating.

• The control shall have the ability to operate a domestic hot water contact that operates during a domestic hot water call.

• The control shall have the ability to limit the number of boilers operated during domestic hot water calls for heat.

• The control shall have the ability to display the current temperature difference between the return temperature and the supply temperature, ΔT.

• The control shall have an option to rotate the firing sequence of the boilers and the option for rotating the boiler firing sequence shall be based on the boilers’ accumulated running hours.

• The control shall use proportional, integral and derivative (PID) logic when staging boiler stages.

• The control shall have an adjustable Minimum Supply water temperature setting to help prevent condensation of flue gases and subsequent corrosion and blockage of the boilers’ heat exchanger and chimney.

• The control shall have the option of an automatic differential calculation in order to prevent short cycling of the stages.

• The control shall have the ability to operate a primary pump plus individual boiler pumps based on the mode of operation selected.

• The boiler pumps shall have an adjustable post purge setting that allows the pump to run for a set period of time after the boiler has been shut off.

• The control shall have the option of staging multistage boilers in either a Low – High sequence or a Low – Low sequence.

• The control shall have the option for a fixed lead rotation and when this option is selected, the control shall have an option for either a first on / first off, or first on / last off firing sequence.

• The control shall have the option for a fixed last rotation.

• The control shall have the option for either an alarm output or a combustion air damper output. If the combustion air damper output is selected, the control shall have an adjustable combustion air damper opening time.

• The control shall have an adjustable minimum inter-stage delay that can be set manually or calculated automatically by the control.

• The control shall have the option of accepting a 0 – 10 V (dc) input signal from an energy management system.

• When operating with a 0 – 10 V (dc) signal, the control shall have an adjustable offset setting as well as an adjustable input range.

• The control shall have two separate lockable access levels to limit the number of adjustments available to various users.

• The control shall have a test button that activates a pre-programmed test sequence testing all the control’s outputs.

• The control shall show a number of current sensor temperatures depending on the access level that has been selected.

• The control shall continually monitor its temperature sensors and provide an error message upon a control or sensor failure.

• The control shall record and display the running hours of each boiler.

• During extended periods of inactivity, the pumps that are operated by the control shall be periodically exercised to prevent seizure during long idle periods.