Weil-McLain GV90+ Installation And Start-Up Manual page 89

GV90+ Series 2
OAS·FIRED WATER BOILER -
Boiler Manual
Troubleshooting
(continued)
Insufficient heat or no heat to on
IAWAIVIIIOI
Electricalaho<:k hazanl - Whe<ever
yoo
see TURN OFF POWER, follow tile Instructions. Faii.Jreto follow
Instructions CO<Jid result in sewre
personal
In , dealll or substantial
dama
e.
• Has It been at least5 minutes since seutng thermostat to
r"
Is
boll6r
System clfC<Jiator operating?
call lor heat? If
no~
walt 5 mlnutes.ls system heating?
• Is thermostat sat to call for
heat?
Remove thermostat
No
I
Yes
wires at boiler and ched< continuity across tile two wires. If
+
circuit Isn't closed, check external thermostat (zone valVe,
• Remove system circulator harness plug from CIR·
relay, etc.) wiring. Correct prolllems and retry.
• Reconnect external thermostat wiring at bofler.
CULATORS plug receptacle (long harness) (see
Figure 93, page 80, Item 4). Ched< with voltmeter
Is thermostat c/rcuff closed (contlti(Jity across wltos)?
across lett-side 120 VAC N and 120 VAC H pins of
No
I
Yes
receptacle.
r-
t
Does · > Oitmotorshow 120VAC across pins?
Are aN rsd Hghts off?
•
Boiler Is In stald>y.
No
I
Yes
I
•
Set thermostat to cal
for
heat
•
+
No
-
and rechOO< QPOratlon.
• Replace IBC.
•
Repair/replace clrcula·
~
r'.
Verify sequence of QPOratlon,
• Retest
tOf'. Retest.
• Walt 30 seconcls.
Figure 75, page 66.
•
Repair/replace wiring.
Retest.
Are a// rod //gilts
off?
•
Check blocl< switch on top of • Walt 5 minutes .
No
1 -
boiler with continuity ci\OO<er.
rL
Is FLAME //gilt on?
+
Are contacts closed?
No
I
1
Yes
No Yes
•
•
Replace IBC .
!
•
Retest.
• If you hav:e sufficient heat - OOiler should follow normal
operating sequence (Figure 75, page 86).
• Ched< across limit
• If you hav:e less than sufficient heat -
switch
contacts with
Is ""'tor
combustion
sir piping free of blocka.ge?
• Walt for cast Iron
condnulty ched<er.
block
to cool
to
room
AlB
contacts c/oS6d?
No
I
Yes
tempera tile.
...
•
Are
bloc/c
switch
Yes
I
No I- • Correct conditions and
• Contact your Wei·
contacts ciOSBd?
+
recheck operation. See Mclain sales represen·
sequence of operation,
Fig· IalNe.
No
I
-
•
Check across thermal
fuse
ure 75, page 66.
l leads w!lll continuity checker.
~
• Walt
&of
bofJer water
to cool
to temperature 20
to
30 °F
Is circuit
c/OS8d? lower than temperature set on
the
UmJt.
•
Replace
sw~ch. No
1
Yes
Are limit
switch
cootacts closed?
• R&tast.
+ +
No Yes
•
Replace
+
thermal fuse.
• Replace IBC.
• Replace
lim~
switch.
•
Retest.
• Retest.
• Retest
•
Excessive bkK::k ten..,erature has been reduced to sale op·
• Boiler water temperature exceeded setting on limlt swttch
orating level Ched< lot low water level or mineral
deposlls
with thermostat callng for heat. Bolk>r Is OK (See ..,.
In sections. Correct before proceeding.
quence
ol
operation, Figure 75, page 86)
• Restart boiler and chOO< sequence
ol
operation (Fig·
ure 75, page 66).
• Also ched< QPOration of seutng llrnh (should be abowl
140'f.).
Part number 550-14-2-783/1012
89