safgard 724 Series User manual

724 Series
Lo Water Cut-Off
Feeder Combination
for Steam Boilers
24 VAC Op rating Voltag
N m ving parts in water.
N fl ats t hang-up r f ul.
Unique tw pr be design. B uncing
water line w n’t cause n- ff burner
cycling r water valve slamming
n ise.
Easy installati n. Quick h k-up
fittings adapt c ntr l t all 8" t 14"
sight glasses.
Simple fast wiring. Can be used with
any standard aut matic water feeder.
Re d nd underst nd these instructions completely before inst lling or servicing this control.
S ve these instructions for future reference.
Disconnect power supply before beginning inst ll tion to prevent electric l shock or equipment
d m ge.
Only qu lified personnel m y inst ll or service the control in ccord nce with loc l codes nd
ordin nces.
This low w ter cut-off must be inst lled in series with ll other limit nd oper ting controls inst lled on
the boiler. After inst ll tion, check for proper oper tion of ll of the limit nd oper ting controls, before
le ving the site.
We recommend th t second ry (redund nt) Low W ter Cut-Off controls be inst lled on ll ste m
boilers with he t input gre ter th n 300,000 BTU/hour or oper ting bove 15 psi of ste m pressure.
At le st two controls should be connected in series with the burner control circuit to provide s fety
redund ncy protection should the boiler experience low w ter condition. Moreover, t e ch nnu l
out ge, the low w ter cut-offs should be dism ntled, inspected, cle ned, nd checked for proper
perform nce.
To prevent serious person l injury from ste m nd hot w ter m ke sure there is disch rge line from
the blow down v lve to proper pl ce of dispos l.
To prevent fire, do not use this low w ter cut-off to switch currents over 7.4A, 1/3 Hp t 120 VAC or
3.7A, 1/3 Hp t 240 VAC, unless st rter or rel y is used in conjunction with it.
Previous controls should never be inst lled on new system. Alw ys inst ll new controls on new
boiler or system. F ilure to follow this w rning could c use property d m ge, person l injury or
de th.
CAUTION A more frequent repl cement interv l m y be necess ry b sed on the condition of the unit
t time of inspection. Hydrolevel’s w rr nty is two (2) ye rs from the d te of m nuf cture.
WARNING
26 Bailey Road, North Haven, CT 06473 • Phone [phone] • FAX [phone] • www.hydrolevel.com

HOW TO INSTALL
R mov gaug glass ass mbly and nippl s r plac-
ing nippl s with two 6" brass nippl s provid d ➀.
Install 1/2" x 1/2" x 3/8" t ➁on top nippl .
Install 1/2" x 2" brass nippl ➃and 1/2" x 1/2" x
1/2" t ➂to 1/2" thr ad d hol in casting ➄.
Not : Casting is d sign d for ith r l ft or right
mounting on gaug glass. B sur to plug hol on
opposit sid .
Thr ad t attach d to casting into bottom 6" nip-
pl . Tight n until casting is v rtical.
Install compr ssion fittings ➆into casting and
top t . Siz copp r tubing ➅and tight n
b tw n th two compr ssion fittings.
Attach control to prob s using No. 8-32 s lf tap-
ping scr ws provid d. Install nippl and
blow down valv (with discharg lin ) in bottom
3/4" tapp d hol .
R attach gaug glass cocks and gaug glass into
nd of 1/2" t s. Pr ssur -trol can b thr ad d
into 1/8" thr ad d hol on top of casting. If pr s-
sur -trol is not us d, plug 1/8" hol on top of
casting.
Attach blu prob l ad wir to upp r prob and
whit prob l ad wir to bottom prob with wing
nuts and lock wash rs provid d.
1
234
567
MODEL - COMES WITH:
➀ (2) 6" x 1/2" brass nippl s
➁ (1) 1/2" x 1/2" x 3/8" t
➂ (1) 1/2" x 1/2" x 1/2" t
➃ (1) 2" x 1/2" brass nippl
➄ (1) 724C manifold casting
➅ (1) 3/8" copp r tub
➆ (2) 3/8" compr ssion fittings
➇ (1) 3/4" nippl
➈ (1) Blow down valv
NOTE: Discharg lin
not includ d.
2

WIRING METHOD A: SAME POWER SOURCE FOR CONTROL AND BURNER CIRCUIT.
WIRING METHOD B: SEPARATE POWER SOURCE FOR CONTROL AND BURNER CIRCUIT.
BURNER
POWER
SOURCE
24VAC
60HZ
NEUTRAL
HOT
DISCONNECT
SWITCH
BURNER
POWER
SOURCE
24VAC
60HZ
BURNER
POWER
SOURCE
24VAC
60HZ
NEUTRAL
HOT
+
0
LIMIT
CONTROLS
BURNER
POWER
SOURCE
24VAC
60HZ
+0
FEEDER VALVE
CONTROL
POWER
SOURCE
24VAC
60HZ
NEUTRAL
HOT
DISCONNECT
SWITCH
CONTROL
POWER
SOURCE
24VAC
60HZ
NEUTRAL
HOT
BURNER
CIRCUIT
DISCONNECT
SWITCH
CONTROL
POWER
SOURCE
24VAC
60HZ
+ 0
LIMIT
CONTROLS
BURNER
CIRCUIT
CONTROL
POWER
SOURCE
24VAC
60HZ
+ 0
LIMIT
CONTROLS
BURNER
CIRCUIT
FEEDER VALVE
A1 Conn ct input voltag (24 VAC, 60HZ)
to t rminals 2 and 1. 24 VAC, 60HZ
must b suppli d to t rminals 2 and 1 for int rnal
op ration of th control.
Install a jump r b tw n t rminal 1 A2
and t rminal P1. Pow r from t rminal
P1 is suppli d to t rminal P2 wh n wat r r ach s
th upp r prob . Pow r to t rminal P2 is r mov d
wh n wat r falls b low th bottom prob .
A3 Conn ct t rminal 2 to burn r circuit
n utral. Conn ct t rminal P2 to
burn r circuit in s ri s with oth r limit controls.
Consult boil r manufactur r’s instructions for
prop r t rminal conn ctions. NOTE: Control is
wir d in s ri s with and b for oth r limits.
F d r Conn ction: Conn ct f d r A4
common to t rminal 2. Conn ct f d r
hot to t rminal A. Wh n v r wat r falls b low th
low r prob , pow r is suppli d to th f d r t r-
minal A. Wh n wat r r ach s th upp r prob ,
pow r to th f d r is r mov d.
B1 Conn ct input voltag (24 VAC, 60HZ)
to t rminals 2 and 1. 24 VAC, 60HZ
must b suppli d to t rminals 2 and 1 for int rnal
op ration of th control.
Conn ct hot l ad from burn r B2
control circuit to t rminal P1.
This t rminal suppli s pow r to t rminal P2 in
normal op rating conditions wh n wat r is at th
prob . Conn ct n utral to burn r circuit.
NOTE: Consult boil r manufactur r’s instructions
for prop r t rminal conn ctions.
B3 Conn ct t rminal P2 to burn r circuit
in s ri s with oth r limit controls.
Consult boil r manufactur r’s instructions for
prop r t rminal conn ctions. NOTE: Control is
wir d in s ri s with and b for oth r limits.
F d r Conn ction: Conn ct f d r B4
common to t rminal 2. Conn ct
f d r hot to t rminal A. Wh n v r wat r falls
b low th low r prob , pow r is suppli d to th
f d r t rminal A. Wh n wat r r ach s th upp r
prob , pow r to th f d r is r mov d.
NOTE: All sch matic diagrams show all syst ms in
th off position. No pow r appli d.
A1
A3 A4
B1 B2
B3 B4
A2
3

INSTALLATION & OPERATION OF FEEDER
A f d valv is suppli d standard with control
mod l 724WF. It is r comm nd d that a shut-off
valv and union b install d on ith r sid of th
wat r f d valv and a by-pass valv and piping
b install d to p rmit r moval of th wat r f d
valv should s rvic b r quir d. During normal
op ration, by-pass valv should b clos d and iso-
lation valv s should r main op n.
PRINCIPLE OF OPERATION
Hydrol v l controls ar l ctronically op rat d.
Wat r is us d as an l ctrical conductor to com-
pl t a circuit from th prob to th control unit.
Th control unit provid s switching contacts to
op rat th burn r circuit and optional wat r f d r.
Th 724 S ri s low wat r cut-off is d sign d to
maintain a saf op rating wat r l v l in th boil r.
Wh n wat r is in contact with th upp r prob , th
control nabl s th burn r to fir (switch contacts
P1 - P2 ar clos d). Wh n th wat r l v l falls
b low th low r prob , th control will d - n rgiz
th burn r circuit. Th control will not r - n rgiz
th burn r until th wat r l v l is r stor d to th
upp r prob l v l.
Th 724WF includ s a f d valv d sign d to
automatically r stor th wat r l v l in th v nt
of a low wat r condition. Wh n wat r falls b low
th low r prob , th 724 will n rgiz th f d
valv (switch contact 1 - A mak ). Wh n th boil r
wat r l v l is r stor d to th upp r prob , th 724
will d - n rgiz th f d valv and r stor burn r
op ration. Th 724CF do s not includ a f d
valv , but do s provid contacts for op ration of a
st am boil r wat r f d r.
The followi g mai te a ce must be performed by a qualified service tech icia :
A ually
• R mov and cl an th strain r locat d on th valv body. IMPORTANT: If th strain r shows signs of min ral d posits coll cting on th
scr n, install a Hydrol v l F d Valv S rvic Kit (Part No. 45-725).
Every 3 Years
Install Hydrol v l F d Valv S rvic Kit (Part No. 45-345). Note: If hard n d calcium d posits hav form d on th brass surfac insid th
valv , r plac th valv (Part no. 45-725).
12 Years
R plac th F d Valv Ass mbly aft r 12 y ars of s rvic .
WARNING Water Damage Pote tial: Failur to maintain th f d valv can r sult in xc ss min ral d posits
coll cting in th valv . If l ft unch ck d, th s d posits can imp d valv op ration with th pot ntial
for ov rfilling th h ating syst m and allowing wat r to scap radiators into th living spac .
F d Valv Maint nanc (WF Mod ls Only)
4

DIMENSIONS
OPERATING INSTRUCTIONS
NOTE: Hydrol v l r comm nds that th boil r
manufactur r’s proc dur s for skimming th boil-
r b p rform d prior to placing th control into
op ration.
1Aft r installation, rais th boil r wat r l v l
until wat r is in contact with th upp r prob .
Turn on pow r and s t th th rmostat to call for
h at. Th burn r should fir imm diat ly.
2Using th boil r drain, slowly low r th wat r
l v l to a point b low th low r prob . Th
burn r should shut down imm diat ly upon a
low wat r condition.
NOTE: Th wat r should not b low r d b yond
a visibl point on th gaug glass.
IMPORTANT: If th burn r do s not shut down in
a low wat r condition, turn off pow r imm diat ly
and r f r to troubl shooting instructions b low.
TROUBLESHOOTING
1If th burn r do s not shut down upon wat r
falling b low th low r prob : R mov pow r to
th burn r and ch ck installation. Ch ck wiring
and mak sur that burn r is conn ct d to th
fourth t rminal from l ft on t rminal (P2). If
wiring is corr ct, ch ck to mak sur th
prob s ar not fals ly ground d. Voltag
b tw n th prob s and chassis ground should
b 120-140 VAC with wat r b n ath both
prob s. A low r r ading may indicat a short d
prob . R mov prob s and ch ck for contami-
nation.
2If th burn r will not fir with wat r at th top
prob : With a voltm t r and pow r appli d at
t rminals 2 and 1: Ch ck th voltag b tw n
th upp r prob and chassis ground. R ading
should b 0-10 VAC with wat r at th upp r
prob . A high r r ading may b th r sult of
poorly conductiv wat r or prob contamina-
tion. R mov prob s and ch ck for contamina-
tion. If th burn r will still not fir aft r cl aning
prob s, contact factory for assistanc .
SERVICE / MAINTENANCE
Th 724 S ri s Control r quir s r gular
maint nanc to nsur continu d, saf op r-
ation. During normal boil r function, s di-
m nt may accumulat in th low wat r cut-
off's prob housing. If l ft unch ck d, this
s dim nt can build up, trap wat r in th
prob housing, and pr v nt th control from
d t cting a low wat r condition in th boil r.
A r gular blow down of th control is
r quir d for prop r op ration.
To flush th s dim nt from th chamb r, th
control must b blown down throughout th
h ating s ason in accordanc with th fol-
lowing sch dul :
• Daily for first w k following control
installation
• Prior to h ating s ason startup in th fall
• Onc p r w k during th h ating s ason
I structio s: Confirm wat r is visibl in th
gaug glass. If not visibl , shut th burn r
off, allow th boil r to fully cool, th n add
wat r until visibl in th gaug glass. Onc
wat r is visibl , bring your boil r back up to
t mp ratur . With th boil r running, plac a
h at r sistant pail dir ctly b n ath th con-
trol casting blow down valv . Op n th valv
and allow th s dim nt and wat r to drain
into th pail. Continu to drain th wat r
until it runs cl an (On to two gallons is g n-
rally suffici nt). Clos th valv wh n com-
pl t d. R pl nish th wat r in th boil r if
n d d.
REGULAR MAINTENANCE
REQUIRED. Failur to
prop rly maintain th control can l ad to
s v r damag to th boil r, oth r prop rty,
p rsonal injury, or d ath.
To pr v nt s rious p rson-
al injury from st am and
hot wat r, mak sur th r is a discharg lin
from th blowdown valv to a prop r plac of
disposal. Failur to follow this caution could
r sult in p rsonal injury.
5

6
LIMITED MANUFACTURER’S WARRANTY
W warrant products manufactur d by Hydrol v l Company to b fr
from d f cts in mat rial and workmanship for a p riod of two y ars from
th dat of manufactur or on y ar from th dat of installation,
which v r occurs first. In th v nt of any claim und r this warranty or
oth rwis with r sp ct to our products which is mad within such p ri-
od, w will, at our option, r pair or r plac such products or r fund th
purchas pric paid to us by you for such products. In no v nt shall
Hydrol v l Company b liabl for any oth r loss or damag , wh th r
dir ct, indir ct, incid ntal or cons qu ntial. This warranty is your EXCLU-
SIVE r m dy and shall b IN PLACE OF any oth r warranty or guarant ,
xpr ss or impli d, including, without limitation, any warranty of MER-
CHANTABILITY or fitn ss for a particular purpos . This warranty may not
b assign d or transf rr d and any unauthoriz d transf r or assignm nt
th r of shall b void and of no forc or ff ct.
26 Bailey Road, North Haven, CT 06473 • Phone [phone] • FAX [phone] • www.hydrolevel.com
WARNING Frozen pipes/water damage. C ntral h ating syst ms ar pron to shut down as a r sult of pow r or fu l outag s,
saf ty r lat d fault conditions or quipm nt failur . Installation of fr z prot ction monitoring or oth r pr cautions
is r comm nd d for unatt nd d dw llings in climat s subj ct to sustain d b low-fr zing t mp ratur s.
051322
SPECIFICATIONS
MAXIMUM PRESSURE: 15 PSI
INPUT VOLTAGE: 24 VAC, 60 HZ
SWITCH RATINGS: 5.8 FLA, 34.8 LRA
SWITCH CONTACTS: SPDT
ALARM CIRCUIT: 50 VA @ 24VAC
Pilot Duty
OPTIONS
Th VXT wat r f d r (availabl s parat ly)
can b us d with Hydrol v l or oth r low
wat r cut-offs to automatically r pl nish
boil r wat r in th v nt of a low wat r con-
dition. Th VXT off rs programmabl f d
amount and f d d lay s ttings. Th s can
asily b s t to nsur th prop r f d
amount and to provid ad quat tim for
cond nsat to r turn to th boil r b for
starting a f d cycl . Th VXT’s digital f d
count r tracks th amount of wat r add d to
th boil r xposing syst m l aks, which can
significantly short n th lif of a cast iron
boil r. Additional f atur s including a manual
f d button und rf d and flood prot ction,
mak th VXT an id al choic for saf ty and
conv ni nc .