Weil-McLain GV90+ Installation and operation manual

®
• Installation
• Startup
• Maintenance
• Parts
Boiler Manual
Series 2
Gas-Fired Water Boilers
Thismanualmustonlybeusedby a qualified heating installer/servicetechnician.BEFOREinstalling,read
all instructions in this manual and all other information shipped with the boiler.Perform steps in the order
given.Failure to comply could result in severe personal injury, death or substantial property damage.
Part number 550-142-783/1012

GV90 + Series 2 oAs·FIRED WATER BOILER - Boiler Manual
How it works •••
1 Integrated boilercontrol
The integrated boiler control (IBC) responds to signals from the room thermostat, air
pressureswitdl,i :n letwatersensor,boiler wa .ter temperaturesensorandboilerlimitcircuit
to operate the circulators, gas valve, igniterandbl ower. Whena room thermostat ca Us
for heat, th e I BC star ts the sys tem circulatorandblower.
The JB C runs the bi O'\\• er to purge the boiler flue passages, then turnson th e igniter and
lets itwarm up.
Aft er igniterwarm· up , th e I DC opens the gas vah-e, rurnstheigniteroff, and checksfor
flam e. Th e flam e must come on within 4wconds or the me willshut down and try the
fu ll cydeagain.
W
hen the room thermostat is satisfied. the IB C turns off the boilercomponents and
wa i.ts (or the next beat ca ll .
The IBC in dicator lig h. ts shownonnalsequence wh en th e lightsare on steady. When a
problem occurs, the JB C flashes combinations of lights whichindica te the most bkel y
reason for theproble m..
Wh ileattempting to satisfy the heat demand, the con tr ol module m oni t ors the boiler
temperature changes via the temperature sensors a nd determ in es wh eth er or not t he
ava il ab le hot water w. tll satisfy th e de mand, only ru nning the ci: rculator. Ifadditional
heat is needed, the sequence
co n ti: n ues.. When DHW (if used) caJJs fo r heat. sequen ce
aboveisbypassed.
2 Transformer
The controltransfo rm er reducesline vottage to 24 voltsforthe gas valve andlimit ci:rc ui t.
3 Blower
The blower pulls i: n ai: r and mi xes it with gas &om th egas valve. Thebla\\'et forces this
m ixturt in to lhe burner fo r co ml xu:tio nin side- the- bo il er ch amber.
4 Recuperator
Therecupenttor is a stainless steel beat ex chang er that increasesboaere fficiency byex·
trading additionalbeat &omthefluega ws, Return waterpasws throughtherecuperator
beforeentering theboiler.
5 Water temperature sensor
The wat~r t~mptra l u r ~ se n sor provides a signal to the conrrol modu le to turn
off rhe gas va l v~ if the temprratur~ in the boiler goes abo~ its setring. (The
circulator wlll
co nrinue to run aslong asthere isa call for heat.)
6 System circulator
The sy stem circulatorcirculates water throughtheexternal (S) 'Stem) piping, The flow
ra . te of th ecirculator i:s controlled by the IBC, depend in gonthetemperatu re of th e wa t er
en t er in g t he bo il er .se<tio n $. Pump m u.< n rema in on boiler- do not remove.
7 Bypa .. circulator
The IBC operates the bypass ci rc ul ator to mi.x hot water fro m t he boil er outlet with
colderreturn "'ater from the S) 'Stem as needed to preventcondensation of flue gas es in
th e cast iron heatexchanger.
Whe n the wa t er returning to th e boiler Is below IW F. th e I BC reg ul ate$ the bypass ci: r·
culatorand
sy stemcirculator flow rates to rai se the return watertemperature up to l4 0'" F
beforeitenters the cast ironsections, Bybalancing these
flow rate s. the IB Ccanprotect
agai: n .st condensation in the cas tironheatexchangere\'enif return water Is aslowas 6Cr f.
Pump mU$ t re mainon boil er - do not re m m-e.
8 Air pre .. ure switch
The ai:r pressureswitchsignals the IBC.teU ing th e controlwhetherairismoving through
th e blower.
9 Return water temperature sensor
2
The water temperat UI'e sensor mo ni tors the temperatu re of th e wa t er entering the boiler
sectfons.Thesensorsendsthis Information to the IBC .The I BC det er mines how m uch
to adjust the cirrulator fl O\\' rates to provide at least 14 0'" Pwater to thecast iron beat
exchanger.
LE G EN D
a Supply to
system> 1"' NPT
b R etu rn from system, I" NPT
c Combustion air lnle t fit ting -
3"' P VC connecti on
d FJ ue ou tl et - 3"' PVC conn tc ·
tion
e Gas va J ve - negati ve p r ~ss urt
regulated gas control
I Pressure/temperaturegauge
g
FJueway inspection port CO\ ' tr
h Stnsor hosetrap
Manual airvtnt
Rel i ef vaJ\·t
k Thermal fuse- a one·timefuse
de v ice thatshutsboileroff if flue
te:mptratureexceeds irs strpo int
m Condtnsate trap line -sh ipped
loose with boiler,
field installed
n Condensatedraincon nection-
W' PVC female
Thi s boiler uses a negarive· prtssurt -
r
tgu l attd gas valve, ser for an ou tl et
pressure
ap pr oxi ma tely -0 . 20"' water
co l umn .
00 NOT set rhe outle t p r ~ssurt higher
t
ha n factory sett ing.
Pan number55 0- 142-783/1012

GV90+ Series 2 GAS·FIRED WATER BOILER - Boiler Manual
GV90+ Series 2 Water Boiler
Part num ber 55 0- 14-2 -783/1012 3

GV90+ Se ri es 2 oAs·FIRED WATER BOILER - Boiler Manual
Contents
How it works ..... .
GV90 +Water Bo il er .
.2
.3
Pie aM read belore p~eding ... 5
Pr epa re bo il e rl ocat ion ....... 6
Installationsm u.< n fonow thesecodes: ... 6
Highaltitude i: nstallatfons .......... 6
Residential garage installation ....... 1
Check orifice plate-replace if necessary. 8
Installcondensate ua p. . . ......... 9
Install h igh altitude air pr ess ureswitchwh en
required {o nJ yabove S.SSO feet) ...... 9
Rotate t he bo il er in to position ...... 10
Perform hydrostatic pressure t
est ..... II
In sta ll w ate r pip in g ........ 12
General pipi: ng informat ion ........ 12
Install re liefvah-e ............. 12
Exp ansion tank •.............. 13
Sys tem wa ter piping m eth ods ....... IS
Orcula t ors ................. IS
Simplified pipe/cirrulator selection ... IS
Baseboardsystem piping -ORCULATOR
'ZOning (p ri :m arylseco ncf ary ) ....... 16
Baseboardsystem piping - ZO NE VA L VE
'ZOning (d irectconnection) ........ 16
Radiatorsystem piping .......... 18
Single· wne radiant h eati: ng or heat pum p 19
Ad;wt b ala n ci ng vah<S , , , , , , , , , , 19
Multi· wne radiant heatiog system . . . . 20
Pipingsnow meltsystems or combinati on
snow melt/space heating ;Systems. . . . . 2 1
Water chillersystems . . . . . . . . . . . 22
Multiple boiler i ns ta ll at ions .... 23
Placing mul tiple boi~s . . . . . . . . . . 23
Conuollingm ul tipleCV90+ bo il ers . . . 23
Pipingm ul tipleCV90+ boil ers. . . . . . 23
Multiple boiler water pip in g •... 24
Easy ·F it• piping installation . . . . . . . 24
Venting & air- ge n Ka l ...... 29
When removinga boiler from an existing
common ven tsystem . . . . . . . . . . . 29
Existingvent tes t procedure ........ 29
Provi de combustion air: .......... 30
Ven t and air termination options ..... 30
DIRECfVENTinstallations
....... 30
DIRECT
EXHAUST installations ..... 30
Combust
io n air contamination: . . . . . 30
Ma nifoldedcombustion air option (or Dl ·
RECT VENT m ultiple boib inslallations . . . 3 1
Air manifold sizing . . . . . . . . . . . . 3 1
Co mm o nwe alth ofMlls sao h usetts
in sta llati ons . . . . . . ...... 34
Vent te rmination requiremen ts .. 35
DIR EC T VE NT - Bo il er r oo m air
ope nings . . . . . . . . ...... 36
DIR EC T VE NT - Sidewa ll with W-M
ve ntfairplate. . . . . . ...... 37
DIR EC T VE NT - Sidewa ll with oepa·
r
ate pi pe s. . . . . . . . ...... 39
4
DIR E CT VE NT - Sidewa ll with 3"
co n ce nt ri c ............. 41
DIR E CT VE NT - Verti ca l with -·
rate pi pes .............. 43
DIR E CT VE NT - Verti ca l with 3"
co n ce ntric ............. 45
Concentric te rmination assem bly
(sidewa ll or vertica l) ........ 47
Ve nt and a ir pipi ng and boiler co n-
n ec tions .............. 48
DIRECTEXHAUST&DIRECTVENT . 48
Follow terminationinstructions . . . . . 48
Insta ll ingvent a nd air piping . . . . . . . 48
DI RECT EXHAUST ONLY . . . . . . . . 48
DIR E CT E XHAU ST - Boiler r oo m air
ope nings .............. 49
Combustion ai: r provisi on . . . . . . . . . 49
Siring combu.<Jtio n air openings . . . . . 49
Specialconstderations. . . . . . . . . . . 49
9V90+ bo il er WITHOUTother ap pl iances
tn room. . . . . . . . . . . . . . . . . . . 50
Air openings . . . . . . . . . . . . . . . . 50
CV90+ bo il er WITH o th er appliancesin
roon1 . . . . . . . . . . . . . . . . . . . .
50
DIR E CT E XHAU ST - S id ewa ll .. 51
DIR E CT E XHAU ST - Ve rti ca l •.. 53
Gas piping ............. 54
Connecting gas supptypiping. . . . . . . S4
NaturalCas. . . . . . . . . . . . . . . . . SS
PropaneCas . . . . . . . . . . . . . . . . SS
Wiri ng ............... 55
Field wiring. . . . . . . . . . . . . . . . . S6
Sta rt- up ............... 59
Freeze protection(wh en u.W) . . . . . . S9
Cl ea n system to remo\>e sed im ent . . . . S9
Wa t er chemistry . . . . . . . . . . . . . . S9
Antifreeze. . . . . . . . . . . . . . . . . . S9
F lll and test wa .ter system . . . . . . . . . 60
Use inhibit or sup pl ied with bo iler . . . . 60
Check/Ve
ri fy wa ter chemist ry . . . . . . . 60
Check imllit:or c.oncm tnr: ion an rualy . . . 60
Checkfor
gas leaks. . . . . . . . . . . . . 61
Verifygas/airorificeplate . . . . . . . . . 61
Checktherm os tatcircuit(s). . . . . . . . 61
In spect/fiJI condensatesyst em . . . . . . 61
Finalchecks beforestartingboiler . . . . 62
Adjustboiler controlsrttinp . . . . . . . 62
Aju.• n boiler cont ro l setti: n SJ> . . . . . . . . 62
Bo iler Eco nomysettings. . . . . . . . . . 62
To st
art the bo il er ............. 62
If boilerdoes nots tartcorrectly ..... 62
Ch eck system and boilerafterstart ·u p .. 62
Cas vatve adjust me nt- attitude O\'ft' S.SOO
re.tONLY ................. 63
Finalchecklist ............... 64
Departmentof Energy eon-.>liance . 65
IBC (Sequence of operations) ....... 66
Operating lnstrustions .......... 67
Annual st art·up a nd ge neral maint e-
nance sc hedule . . . . . . . . . . 68
Annual st art-up . . . . . . . . . . 69
Address reported problems . . . . . . . . 69
Inspect boilerarea . . . . . . . . . . . . . 69
Inspect boiler in terior . . . . . . . . . . . 69
Inspect condensate drainsyst e:n l . . . . . 69
Inspect all pipi ng for leaks . . . . . . . . 69
Inspectgas piping . . . . . . . . . . . . . 69
Inspect the watersystem. . . . . . . . . . 69
Check watersyst e:n l chemist ry . . . . . . 69
Inspectexpansion tank . . . . . . . . . . 70
Inspect air openings . . . . . . . . . . . . 70
Inspect ven tsystem andair piping . . . . 70
Inspectboil er heati ng surfaces . . . . . . 70
Inspectig ni ter . . . . . . . . . . . . . . . 70
Inspectt e:n l pe:ral'Ute mi.xi: ng system . . . 71
Inspect additional conuok and cutotfs . . . 71
Inspect gauge5 . . . . . . . . . . . . . . . 71
Inspectblower mot or . . . . . . . . . . . 71
Inspectoiled·beari:ng circulaton . . . . . 71
Inspectsupplytemperaturesensor. . . . 71
Inspectboiler relief valve . . . . . . . . . n
To comp l e1< An n ua l Slan·up, perform
startup and checks . . . . . . . . . . . . n
Review with owner. . . . . . . . . . . . . n
Se rvi ce & maintenan ce . . . . . . 73
Cleaning boil er heati ng surf:lces . . . . . 73
To re move theblower assembty . . . . . 73
To dea n heatingsurfaces . . . . . . . . . 73
To dea n the burner . . . . . . . . . . . . 74
To replace blower assembly ........ 74
Inspecting an d dea n ing therecuperator 74
Tro~ es h oo ting .......... 76
VERIFY PROPER OPERATION AFTER
SERV ICING ................. 76
Before troubleshooting . . . . . . . . . . 76
Check the following . . . . . . . . . . . . 76
Checkingtheair pressure switch . . . . . 76
Ig niter .................... 77
Gas Valve . . . . . . . . . . . . . . . . . . 77
Blower Housi ng . . . . . . . . . . . . . . 77
Thermal fuse . . . . . . . . . . . . . . . . 77
Returntemperaturesensor . . . . . . . . 78
Supptytemperaturesensor . . . . . . . . 78
IBC (integrated bo ilercontrol) . . . . . . 79
IBC indKat or Li ghts-lockoutmodes. . 79
IBCin<iiolt« l iglu> - non·~m<><l<! . 79
Installation a nd serv i ce
ce
rtificate . . . . . . 90
Repla ce ment parts . . . . 91
Dimensions and ratings. 1 02
Handling ce ramic fiber and fiber-
glaoo
mat erials. 106
NOTE S .............. 107
Pan number SS 0- 142·783/1012

GV90+ Series 2 OAS·FtRED WATER BOILER - Boiler Manual
Please read before proceeding
Hazard definitions
The following defined terms are used throughout this manual to
bringattention to r. heprestnce of hazards of va ri ous ri sk lt•ttlsor
to i mpo r tant i nf or mat i on conce rn ing the li fe of the pr od uct.
lnd icares pr t.Se n ce of hazards th ar w lll cause sevt- rt
perSona l injur-J'• dearh or substa ntial prope r ty
damage.
lnd icares pr t.Se n ce of hazardsthat can cause sevt- rt
perSonal i njur) '• dearh or substantial proper ty
damage.
!A CAUTION 1 lnd icarespresence of hazardsthat will or can cause
mi no r ptmna l inj ury or pr optrty damage.
NOTIC E
IAwARN IN &l
NOnCE
Jndicares speda l in srruct io ns on in sra ll at i on.
Opt-ration or ma intenance th ar are i mpo r tanr bur
no t related to ptrso nal inj ury or proptrty damage.
Installer- Read all instructions. i nd uding th is
man ual and all othe r in for mation shipped with th e
bo il er>before installin g. Perfonn steps in theorder
gi
.. · tn.
U ll er- Thi s manual isf or use only by a qualifi ed
he-at in g installer/service technician. Refe r to User's
Jn:f'onnation
Ma n ua J fo r your referen ce.
User -Ha\'t this bo il er serviced/inspected by a
qualified service technidan,at lea stannually.
faj lu re to comply wi th th e above could res ul t in
sevtrtpersonalinjur y, deathorsubstantia]proptrty
da.mage.
W~ i tt in the CP nu mbtr in the space provided on
the Installationcertificate on page 90 if notalready
shown.
\Vhen call ing or wr itingabout the boiler- Please
have theboil er modelnwnber from the bo iJ tr raring
label and the CP number from the boi le rjacket.
Consider pipingandinstallati on whendetermi ni ng
bo il er location.
Any claims fo r damage or shorrage in shipment
must be filed immedlatel y against the transportation
companyby theconsignee.
Commonwealth of Massachusetts
When the boi l-er is installed within the Commonwealth of
M..,.chu.setts,comply with <he following.
This produ ct must be insta ll ed by a licensed plumber or gas
fitter .
Ifantifreeze is used,a reduced pressure back-flow preventer
d.,;ce sha ll be uStd .
tf si dewa JI \.'tnt or ve nr/air is insra ll ed> see instructions on
page 34 .
Part n um ber 550-1+2-783/1012
~WARIM I Fa il ure to adhere ro the guidelines on thi.s
page can r esu ll in severe personal i nju r y,
Cleath or substantia]proptrtydamage.
When ..,,.,.;cing boiler-
To avoid electric shock, disconnecrelectr ica Jsupply
before performing maintenance.
To avoid severe burns, a ll ow boiler ro cool before
performing maintenance.
This bo il er contains ceramic t'ibtr and fibe r ~ l ass
materials. Refe r to the WARNING and instructions
on page 1 06.
Boiler operation-
Do not bloc.k flow of combustion or \ <entilation air
to boi l er .
Should ""erhNUng occur or g .. aupply 11111 to
tMit off, DO NOT tum offordisconnect electri cal
sup. P.Iy t ~ ci rculator. Instead> sh~r off thegassupply
at alocanon externaJto theapphanct.
Do not UM thla boilerHany ~h .. _.,under
woter. Immediately call a qil3lifi ed s ervice techni-
cian to inspect tht boi le r and to rtp l.act any va: rt of
the controlsystem andanygascontrol that hasbft.n
under wate r.
Combustionair-
DO NOT In sta ll combulllonairIntakewhwethere
It a rltk of combustion air contamln.Uon.
Carbonmonoxide detector-
Fo r OII'Cid Exhaustuni ts, acarbon mo n ox i de detec -
tor is requir ed in th e bo il er r oom . Thecarbonmon-
oxide dttecror must be wired on
th e same electri cal
circuit as the bo il er.
Fo r Direct V•nt units, a ca rbon monoxide dttecror
that i.s wirtdonthesameelect ri ca ld rcuir as theboiler
is stro nglyrecommended.
Boiler water-
Thoroughly flu sh the s ystem (without boiler con-
neo ted) to removeS<'dinlenl TbehbUI - ellic.ienc y heat
exd1anger can be damagedby build-uporcor ros ion
due tosedi mt nr.
Do not lL~t JH:trole um-based dea ni ng or staling
compoundsin boi
le r S)'Stem. Gaskets andseals in the
system
may bedamage<t. This can r esu lt in substantial
property damage.
LNk o ln boiler 0< piping ,.....t be repeiN<I otonce
to P<8Yenl moke-t~p woter. U se thlo boiler ONLY
In • ciOMd-toop system. Contin ual fre.sh make -u p
wat-er w ill rtduct bo il er l ife. M in eraJ bu il dup in heat
exchangersreducesheattransfer, ove rh eatsthemate-
ri als, an <I cause.s tanure.Addition of oxyge ncarriedin
bymake-
up water can cause intern al co rrosion.
Do not add cold w.ter to hot bolter.ThennaJshock
ca n cause heat exchanger to crac k..
Freezeprotection fluid• -
NEVER u.se automoti\·t orstandard glycolantifrtt:ze.
Use only freeu- pr o te c tl on fluids made for hydronic
systems. Fo ll ow aUguidelinesgi,· tn br. the antifreeze
manufucturer. Thoroughly
dean ana flush apy re-
placeme
nt boiler system that has used gl )'cO Ibefore
m sr.a ll ing th e n ew boi le r.
5

GV90+ Series 2 oAs·FIRED WATER BOILER - Boiler Manual
Prepare boiler location
Installat io ns must follow th ese codes:
Lo<a l, srat:t, provincial,national codes,J aws, regulations and ord in anc~.
National Fuel Gas Co de , ANS I Z223.1 -latest edition.
Standard for Controls and Safety Devices for Au tomatically Fired
Bo il ers, ANSf/ASME CSD-t, when r ~u i r M.
National Ele ctrical Code
ForCanadaonly: Bi49.i or Bl49.2 InstallationCode and CSA C22 .1
Canadian EJect r icaJ Code Pa rr 1andanylocal codes.
The GV90+ bo iJ t r gas manifold and con tro ls m~ safe lighting and other
perrormancecri te riawhenbo il erunderwenttestsspecifiedin ANS I Z21.13
-latest edirion.
1 MOneE 1 For th e Commonwealth of Massachusetts, read and fo ll ow
rhespecial instructionslocated on page34 of this manual.
Insta ll the bo i kr so controlS)'Stemcomponrnts ~ protected
from ti'lpplng or spraying water or ra k'l dur ingOptrntion.
Al lowin g. these compone nts to become wet cou ld cau~ a
bo iler faiJu rt, resulting in severe personal i nju r y, death or
substantial proprrtydamage.
H ig h altitude Installations
GV90+ bo il 6' <Mirols •utofililitAIIy toduttinput wit h ina~ing alritudt.
See Fi gu re 1 for estimated inp ut at altitude as a percentage of St:a level
i np ut. Multiply the bo iler sea level input b)•this ptrc~ntage to obrain the
est imated high aJtitude i nput . Note that the length of the •tenting systttn
wi ll also h ave a min or impacton input. Refer to the ve nt supplement l' ..,r
fur ther in fo rmation.
No mo dificati o ns to the boiler s hould be nece ssary for installatio ns up to
s.soo fee t above St:a level. Fo r higher e-levations . the air pressu re switdl
musr
be changed to aspttial high altitudeswitch. Refe rro thehighaltitude
kit instructions, page 10. Note that the gas \<a l ve outlet pressure mu~ be
checked (andadjus ted if necessary) fo ll ow in g insrructions onpage 63 .
N OTICE
M OnCE
DO NOT oldowall vtnt DIRECTEXHAUST APPUCAnONS
ar alr i rud~s abo\re s.soo feeL Si dewa JJ ventingis only allowed
for DIRECT VENT app lications ( ducted combust i on air ) nt
altitudes a1x we s.soo fee t
Ve nr length aJso affects bo il er input- the bo il er auromati-
ca Ji yderatesrocompensatefor pressurt &oss through the vcnL
See the d~rate values give n in Figure 109, page 103. Fo rhigh
alrirude
inst:a Uartons, m ul ri pl y ihe% in Figure 1 rimes tht'
\'ll ]ueshow-n in Figure 1 09 ro d~erm i ne input vs sealeveL
Service clearances
When possible. ins ra ll GV90+ bo ilers wir.h dea.rances at least as large lt.'i
shown in Figure2 fo rbest service access.
Flooring
The GV90+ boiler is • ppr ove d for installation on combustible fl ooring,
bur
mu.sr neverbeins ta ll ed on carpeting.
6
Do n ot ins rall bo il er on carpeting even if foundation i.-.
used. Fi r ~ can resul t, causing severe personaJ i nju r y, death
or subsran tiaJ propertydamage.
Figure 1 Estimaled GV90+ input at altitude
Altitude
% Sea leve l Input
( fee t )
1 000 97
2,000 93
3,000 90
4,000 87
5000 83
5,500 82
6,000 80
7,000 77
8,000 74
9.000 72
10,000 69
Figure 2 Serviceclearances(recommended)
TOP VI EW
-··
W"'l
~ 6'
i ml"
0
i%
- ~ """ ~
~
36'
,. .... >
...
lir
8GIIL>r
rront
:w
••
I
'
W•ll cr oo:nn.ctlo-1!
FRON TVIEW
-·
C~ l na
l
I
~ -
••
::1
3:
! j
36"
R. ,. , Ql
s·
rln
- ~-
hool
Fl .. ..-.
l•.an num ber 550-l-42-783/10 12

GV90+ Serie s 2 fi A !i -fll ~o w _".,. IIO l L-1!11 -BaU er M anua l
Prepare boiler location (continued)
Foundati . on
Providt a .sQiid b r:lck or <Q . ocmo foundation pad it llny oi' the fol l owing
is possible:
When the floor ca .n becoll)f flood~
Whto (hr: boiJI(-r mbuntin_g ak:il is n ot l. e're l.
When a high -profile condensaie pump is u sed, provide a foWldaiion
bigh c:-nOug h tl:\at lhr:GV90+c(mden,sat,t cOnnecti l )n is at least as hfgli
-as the t.Xmd( n sat~ pump inl t-r c(u i. ne<tio u.
Figure 3 Min im um fll<J!ldalion dimeosians (inches)
Boll or model w L H'
""""
G~ / GV90+4 11!;
301'
2
GV90+SI GV90 +6 16 371' 2
~
• lnCI'tllk heighl if nttded LU auo re
e;mdcmioll !rnp iltlil<U~ ilHilluv~ inlet -------= ~ ---~-- + - · ~ ::..,
vf condc"nsate puJnp. v/Jttn u&erd.
Residential garage Installation
Precautions
Take the fo ll ow i ng sptcial precautions when installing r. he builer ln u
residmtiaJ garage. If the bo iler is located in a residential garage)~ ANSI
Z223.1,parngraph 5.1. 9:
Mo un t the bo lltr a min i mum of 18 Inches above the floor of the
garage ro assutrt the burner and ignition devices will be no J~ thon
18 inc . bes abO\~e the fl oor.
Locate or protect the bolktr so it cann ot be damaged by a muving
\'fhi de.
Minimum clearances
I AW AHNING I
You can in.s mll GV%+ bo iJ ers in spaces s ma ll er thA H Fig-
ure 2. page 6 recommended servi ce dearances. but n ever
smaJ Je:r th an shown in Fi gu re 4.
I nstallat i ons wi th clearances less th an shown lP Fig-
ure 2, page 6 musr ha\'f air ope ni ngs si ud and l tKat.ed as
shown in Figure 4.
Alwa ys providearleastscrewdri\'frclearance to jackrtfront panel St."t't'\'f' s
for rt:mO\'al of fronr pane-l for inspection and minor sen·ice.
Iftheboilerc-annot be serv~ In place . pipe the boi l er with uruuus
and i so lati on valves so it can be sl id ou t of rhe space and krvic«< iu
an adjacent area.
The space has to be equ ipped with a door so boiler can be ue<:cs.'icd.
unpiped and ~ moved.
Part nu m ber 550-1+2 -783/1012
Figu re 4
Min imum ci~(J$ - whoo
clearancas me lliSs th an rocom •
mended $ervice clearances olFi g-
ure 2, page 6, inslali as shown below:
TOP VIEW
... 4_:..
m in
Fr ont
Wall
t
10"
min
~ f~ .
El<>iler
t op
Wal l
A ..Arta ad ja ct:n~ «> ac:-cos d<l(tl' mus ~ lko acct!1~ible.
and m\!S~ allow for ~(tval () ( l,heGV90,..boile.r
f ot" .se-rvict-.
iNo o tJ~r ... pplilnC'I:' or a. i.r mowr (~x hau s t l1 1ln,
etc .) n'my l,t m.JwHel;l in th~ samt fpacc.",
B ..Aca.~DOOR IY ilh fft'.AA nir upenin~tr.:
C !ProVide 1,2) Freshait ~ pccios< - ~odl Wfth al.
l~mst 15q. inch p er UM)U Btu'l1 or bolter input
~
f'
SI DE VIEW
C ol l lhg
6 1' mll ll' l -Accessdoor t ,.
+ m.,
co:::
1i
4. -
Bo11 ~ l ,r~
-i: ...
"
£ &i
dll
"""
6
11
l'I'W( l F
lo cn
NOllC E SPECIAL REQUIREMENTS
FOR AIR OPENINGS : Flif it;,tiill•ti<lill
~-lith dta tan ceo. lt.'.-t than rec ~: J"mm tndtd
&t:tlfic.e dt:tr'ances{Fig ure 2. pagt 6 ). b ul
no klu than shownIn Agure 4 - An
occess door must: be provided,fitted wlth
LWO iti.r ypw.io&S a5 shllWn io Fit.'l.trt' 4 ~
Each ltl)t-nirtg, mlJstba\ t: .i ft« n l' ea nu
l es~ t.lun J ~uttre inch pt r I OOtl Btuh
iurut uf tt,e- GV90+ boilc:r iu the spacr.
DO NOT apply lht air aptnlng alzH
given In Aguro 42, page 36 or FJg ..
ure 60, pa;. 50 .
7

GV90+ Series 2 oAs·FIRED WATER BOILER -Bo ll er ManuaJ
Prepare the boiler (continued)
Check orifice plate - replace if necessary
TheCOf'l'tltCtortflceplatemustbe used. Fa iJu rt to do so
will resuJt in severe persona]in jur y. death or substantial
propertydamage.The bolltrls shipped with a natural
gas ortflct plate. h MUST BE CONVERTED to uu
propane.
Natural gas:
For n atura l gas installations. Inspect the sUver gas/air ortflee plate
marking. It must be the same as the boiler size. If the orifice plate is
stamped with anothe r si u, obrain the co r rtct platefrom your who le-
saler.The bo il er si 7.t is sramprd where the .. X "' isshown in rhe plate
stamping. Figure6.
Propane:
For propane insral la ri on s, nplac• the sliver gas/air orttlc• plate
with the redlwhtte plate , perfo ll owing instructions. Ensure the r ~
white plate bo il er siu is co rrtct fo r the GV90+ bo il erbeing installed.
The bo il er siu isstampedwherethe
1'X
.. is shown in theplatestamp-
ing. Figure6.
Also fill o ut the propane label in the com-ersion kit andattac.b to the
lefrside of thejacker,abovethegasinletopening.asshown in Figure5,
Orifice plate installation, when required
AcctsS th e bo ttom of tilebl ow · er housi ng asshown in Figure5.
To inspect
th e plate on ly. read the marking on the plate edge. It
musr read rhesameas · th e bo il er Si 7.t and fuel , as fo ll ows:
Boltr model Natural
gas martdng Ptopane mar1dng
GV90+3 NG3SEC LP3SEC
GV90+4 NG4SEC LP4SEC
GV90+5 NG5SEC LPSSEC
GV90+6 NG6SEC LP6SEC
To r ep l ace r. he plate. usinga maooal scn wdrtver or nut Qotver . see.
Figur e6:
1. Loose n screws 1 and 2 two fu ll turns.
2. Remove screws 3 and 4.
3. PuiJ the gas/air oriffice plate forward to remove it .
4. Sl id e in th e n ew plate as shown in Figu re 6. T he nd side of a
propane plate nut go next to the bloww housing.
5. Rep lacescrews3 and 4.Tighten all fo ur screwssecurelyand uni-
formly. DO NOT overtighten. DO NOT exceed 40 inch -p ound$
torq u e.
6. lk nd down plate label rabatscore mark as shown in lower right
comerof Figure6. it
em 10.
jAwARtM I
8
DO NOI' use elect ri c or pnewnaticscrewdri\·ers to re-
move or tighten
r. hegas/air boss saews. Hand-tighren
onl y, usi ng manuaJ SCTtWd ri \·er.Shou ki rhe torqueexcted
4() inch-p ou nds. the th readed holes co ul d str ip ou t,
causing an inadequate seal ofthe orifice plate . Failure to
properlyseal theplate to thehousingcould resu lrina gas
leak.caus in gse\rereperson al injur y, death orsubstantial
property damage.
Figure 6 Check for c orr ect gas o r~i c e plate
A :R.emow j s.cktt. &oot
p an~l to aa:~$ thf'bot-
.m m ~ide-Qf t he bl ower
housing.
B Co. mp lcte1t,el'fopane
connrsion labelind
ud -
«1 Wit h th.e COP\ttn i Qn
kit. Insr.a.IJ labt. loo.j.:td:d
ld'tt ida , 11$ Mlawn.
~ t he f;Joil~ oo.lts ba ck,.
on theskid 8$ shown, !Jn til
yo u ~love chocked thr g;oi/mr
~ ri6ce plateand n!pl.aoe it if
11cce658t y.
Figure 6 Fo ll ow in sv uctJonsto c he ck 0< replace
gas or. ijice plate rx· = boiler size)
1-4 .!ia'twi-follow lt • itrt~t:Ubnt fot l ~lns and li r;htal.ins;
S C:a~a.il:' manifold
6 Fn,nl ~ ti on., bouamvi ew, campon nu dtull.tomiJkd
7 $Me $bcw.tttmu.tt po;lnt t (I'Wa rd -aif lltlt1h ttte- WARN lNG
llibtf fll.de lO r1At unl ~ WH'ITI:-d de fo r propane gM
8 PtopuleOtifictplate.RBDaoe6ideandWHIT.Eon th~
4tbi:r ( ttd skit n\11St ~ dw ~rhou..~
9 Natw-a:lg:uotifio:e plate . SIIYE!R
10 Orificepbteafterbendtngalong Kote mack - l.tbel 111
\liu"b lt w l ~ im.UJ IM
P3n num ber SSQ-142-7831 1 01'2

GV90 + Series 2 oAs·FIRED WATER BOILER - Boiler Manual
Prepare the boiler (continvedJ
In sta ll cond en sate tr ap
I. Btlo re plac ing the boiler in pos 'irton, install the condensate. tr ap
lint,shown in Fi gu re 7.Itemsshownare pr O\' ided wi rh the boiler.
Slop 1 Attach the flue draJnh ose (C) to the in-liue flue drain
nip ple (B) .
Step 2 Slide a scTtW driver or prnc iJ through the condensare
dra in n ipp le (G).
Slop3
Slop4
Step5
Slide r. heend of r. hescrewdri\'fr or ptncil in rothe open
end of t ibe flu edraJn b ose (C).
Feed the in-line flue drain (A) assembly into the flue con-
nection (D),guidingthe
flue drain hose th ro ugh th econ-
densate dra in nipple (G) with r. ht screwdriveror ptnciJ.
Press the in-line flu edraJn( A) into the flue connection
(D) and thro ugh the se al r ing until it reaches the srop .
Thentighten tlie flue connection b ose damp to secure .
The flue drain bose (C) sho uld now extend down past the
end of tilecondensate drain n ipp le (G).
Slide t he U-cl amp (F) over the co ndensate trap tee(E)
and i nt:o r. he two ho l es in the rai l. Atrach th e twonuts pro-
vided tc> the U- damp and righren rosec ure the condensate
trap tee ro ther ai L
Sl ide l'he ends of the condensate trap hose (H) on to the
con densa te drain n ipp le (G) and r. he condensate trap tee
(E).Secure thecondensate trap hoseat each end with tht>
hose damps (J}.
IA WARNNG I Choc:k
tho holght o1 th o condonsato trep , .. outlot,
Bef o re rotating the bo il er i nto pos ition, me asu~ lhf"'
distttnce from the con densate t~ ou d ~ ro the bottmn
of th .e bo iler mountingra ll s.When the boilerisplaceio
position, rhe co ndensate tee outlet musr be higher Lb an
the condensa te pump inler connection (wh en a con-
densate p ump is used). Increase the foundation hefghl
if nt<tSSary.
Part n um ber 550- 14-2 -783/1012
Figure7 Insta ll condens<~ l e trap
A lo-Outdnin
Fint.hed MMtnbty
B Au..e draln nfpplt
c Flu.t dni:nbose
0
'f1u.t c:anne:.don
E Co n.;Jcnsalf' tnq • let
F u~~ud oo L~ (oot,
•b -)
G Con den~itt dn.lri
nipPle
H Con denAuo lnlf' hcl.l;e
J H
~ · d.amp~
9

GV90+ Series 2 oAs·FIRED WATER BOILER - Bofler ManuaJ
Prepare the boiler (continued)
Install hi gh al ti tude air pressure switch
when requ i red (onl y above 5,500 feet)
1. For installations at altitu de mo re th an S.SOO feet abo\re sea level:
a. A special high a ltitude airpressure swirch i.s r ~u i r M.
b. The gas valve outler pressure seuing mu st bt checked, and
adjust~ ifnecessar y) per the instrucrions on page63.
" IA " w " AR = IING =~I Failure ro check gas va l ve oudet pr ess ur e and adjust, if
necessary> couJd result in St'\'ff't personal injur y, dearh
or substantial proptrty damage. Ca refu ll y follow the
gu idelin e$ gi ven in this manual
2. Obta in the GV90+ hi gh altitudekit from )'Ou r l oca lWeii- Mcta in
distributor. The hi gh altitude kir co ntains the high altitude air
pressureswitch.
3. See Figure 8 (sw itch shown with wi res removed}.
a. Remove the two (REO) contro l wires from the air pressure
swirch spade te:rmi nal s.
b. Remove r. he factory-installed ai r pressure switch (loosen rop
screw and remove bottom screw holdingswitch to jad:er in-
tt'r'iO r panel).
c. lnsraU r. he high alri r.ude air pressure switch in the same loca-
tion.
d. Cart fu ll )•replacethe hOStS on rhe new switch. with the rtd hose
on the hose ba rb cloStSt to theelectrical spade connecrors.as
$hown in F i g"~$. Th¢whi!¢ hQI¢g ~o n !h~ o!'h~rh~ba r \>,
e. Replace the two ( RED ) cont rol wires on r.he new pressurt:
swarch spadete:rmi naJ s.
Rotate the bo i ler I nto posit i on
!A CAUTIO NI Boilerisshipp<d on backside.lt must b< taken off skid
and rora ted inro co rrect position.
Afterinstallingcondensateline.inspecting(replacing if necessary) r. he
gas/alr orifice and Installing t he highallilude kit ( If required), m ove
the bo ll t'r' near its position.
Figu re 9 shows r.he boiler with r.he front and top panels r ep laced.
These pantls may bt left off if desir ed unr il rhe insrallarion h as bet- n
completed.
Bo iler i.s h eavy andcon ta in ssomesheetmetalpartswhich
may have sha rp edges. Wea r giO\'fS when h and ling and
rake pr ope r precautions when mO\'ing. Failure to do S6
will resuJt in St\'frt persona]in jur y. death or substanri al
property damage.
Refer to Figure 9forplacement sequence as fo ll ows:
1 W ear hNYY gk>ves -cartfu ll y roratt r.he boiler over onto its
base ra il legs.
2 Clip the shipping strapsecuringtheskid to the bo il erblockas-
sembly. Remove th~ skid and strap.
3 Attach the)ack tt rtar panelasshown using (4) II Ox ~»screws
pr O\<ided in theaccessory bag.
10
Figure8 Air pressuresw it ch moun~ n g
1 lntmtw poliJII!:I COl?
2 J~1 ld1 sid~ panel
3 Air pres- tuft' !M"i t cb
4 WHrTEb oilli-
5 ReD-
8
MoUnlin.l-i.::r"""
Figure9 Follow instruct ions toperloon the s te ps
sh ow n bgtow
P.anntunberSS0-142-7M/10 12

GV90+ Series 2 oAs·FIRED WATER BOILER- Boiler Manual
Prepare the boiler (continvedJ
Perform hydrostat ic pressure test
Pressure test bo iler befor• attaching water or gas piping (exctpl as
no ted bel ow) or electrical supply. Remo ve jacket top panel before
pro<t<ding.
IA WARNING I
Use two wrenches wh.en dghtenlng water piping at
bollar , us i ng one of rhe wrenches to preve nt the boil~r
interiorpipi ng from tu rni ng . Fa ll u~ to support the bo i ll"r
piping co nnectionstoprevent them from turn i n goo~.Jid
caus.e damage to bo iler components.
Prepare boiler lor test - see Figure 10
Stop 1 Conne c> t a bose from watersupplyto fill aod drain boiler
fo r h)rd rosraric test. Hose is nor included with boiler.
Step2 Con n ect h ose ro bo il erdr ain vahre. Mak e sure hosecan
also be used to dra in bo ilerafter t es t
Step 3 Rtmo ve I" nipple. I" tee, bushing and pressure/tempera-
turegauge from accesso ry ba g. Pipetoboilersupply co n-
nection asshown. Use pipedo pe sparin gly.
Step 4 Connecta nippleand shuroff va l ve tosystem supply
connection on th e 1" tee . This va l ~ w ill be used ro bl eed
alrdwilng tbe 611 . Valve and nipple are not inc lu ded "ith
bo il er.
Step 5 Connecta nippleand shuroff va l ve tosystem rerum
c-Onnec.ti.on at drc.ula tor flange .This valve will be 1.lSled to
bleed alr duringthe fill Valve and nippleare not included
wi
th bo il er.
Step 6 Insta ll a o/4 • pipeplug in the rtl i tf va h·eopening. rop of
the rear bo il er se ction, asshown. Plug is not incl uded wi th
bo il er.
Fill a nd pressure test
I. Connect 611 watersupply throughdrain v alve ,ltem 2.
2. Fill boiler wirh wate r ( be sure bl eed valves at 4 and 5 areop01).
3. · when wate r flows fr om bl eed valves, shur off water at dta ln
\'ll l ve.
4. Close bl eed va l ves.
5. Slow ly reopen drain va l ve (item 2) until test pressureof45 PSIG
(or 1.5 times bo iJ tr rel ief va lv e setti ng- NEVER MORE than
75 PS IG) Ls reached on <he pressure gauge.
6. Tesr at thispressure for no mo re than 10 minutes.
IA WARNNG I Do nolleave b oiler unattended. A co ld ll~ l er fill rould
expa.nd andcauseexcessi ve pressure,resulting in Si!\'t're
personal injur y, death orsubstanti al property dama.g e.
1. Make su re co~rant gauge pressurehas been maintained through-
out test. Check fo r l eaks. Repai r if found.
I AWARMNG I Leaks mu st be rtpa iredaronce. Failure t:odoso can dam·
age boiler,resulting insubstantial propertydamage.
t ~ j • Of!Hj;l
Do not use petrO leum-based dean in g or sea li ng CQm -
pounds in boiler
sysrem. Severe damage to bo il a wm
occur, r esu ltinginsubstantial properr,•damage.
Part nu m ber 550-14-2-783/1012
Figure 10 Pip ing c on necli ons for hydr osta licl esl
Drain and remo vefittingo
1. Disconne.:.t fi1l water hose from watersource.
2. Dr al11 bo b t: r at dr ai n vahll: or out hose,w hic hever pro-
v id t.s best access todmln. dost drain valve tu ldreJnovt
h~ after cl.rnining..
3. Rto:m JI)\'e l'lug {i tmi 6) from r ditfvalve rappU\8;
4.. lso la.tion viti \'ell: at<" m. L uif'C!'d 10 enableservicing uf th(
boiler's temp«ature Sc.'nSor.
11

GV90 + Series 2 oAs·FIRED WATER BOILER - Boiler ManuaJ
Install water piping
Use two wr encheswhen tightening water piping at
boller, us ing one of r. he wrenches to prevent the boiler
interiorpiping
from turning. Fai lu re rosupporttheboiler
piping
ronntction.s to pre\re nt them from turning co uld
cause damage tobo il ercomponent:s.
The cast iron heat exchanger r eturn temperature mu.s~
be kept al or above 1 4WF du ring all times of optrarion
to prevtn.t po ssib ilit y of corrosion due to condensatio n.
This is done auromati ca ll y, us ing the bo iler's inte r na l
ci rculators. DO NOT rtmove or ramprr with these cir-
cuJators. Fa llu ~ rocomplycouldresultin k\'t'rt pe-rSOnal
i nju r y, death orsubstanti al prope- r ty damage.
General pi ping I nform ati on
Minimum pipe siz:e for boiler loop piping
Figure 11 Provide boi ler loop piping no smallerlhanli sted
below (based on20'Ftempera tur e ri se)
Boiler loop pipe size, Minimum
GV90+3 or 4 1"
GV90+ 6 or 6
Additional limit controls
Follow ingstandard industrypracri ces. if installation i.s tocomplywi th
ASME or Canadian r equ i r~men ts, an additio nal high temperature
llmtt
may be net<led. Con su lt locaJ r ~u i remen ts for o th er codes/
standardstodetermi
ne · if needed. W i r~ as shown in Fi gu re67.page56.
lnsta
JJ a manual r e-set high temperature li mit between the boiler
and
th e isolation valve.
\\fi re the manual reset limit in series with the bo il er limit con·
rro l.
Set the manual r es-et li mit control at least 200F above the boiler
limitconrrol St-rt i ng (maximum setring 2200F).
Low wa1er cut-off, when required
Alow water cutoff dcwlc• isrequired when boil er isinsralled above
radiationl
e-.-e lor by ~ta i n stat~ orlocalcodesor i nsu r anc~ companies.
Use low wate rcutoffdesignedforwaterinstaJJations.Electrode probe-
typeisrtcommended. Pur chaseand i nstall inteeinsupply p i p i ng~
bo il er.\"'irecontact as .shown in Figu r ~ 67.page 56.
If bo il er i.s connected to heating ro il s located in ai rhan-
dling units where they can
be exposed to refrigerated
air, u se fl ow control \'lllws or o ther automatic mean sto
p r ~\rt nt gravity circulation duringcoo li ngcyde. Circu·
Jation of cold wat~r through the bo il er co ul d r esuJt in
damage r:o the hear exchanger, causing possible seveTe
personal injury.dearh orsubstantial propertydamage.
Backflow prevent<!"
\"/here required by codes. install a backflow preventerin the cold
water fill Une , as shown in s uggested piping diagram s on fo llowing
pages . Install ac. beck \'alve if a backflow pre't<enter isnot installed
t2
Air separator
lnst•ll ali air N)>lrator in tli< pip i. ng as shown ir1 th is
rnanua l. Fur .si n gle-1.onc-- .syskr ns.. install the !Ur -separator
in Lht- rrlllrn piping a&- :shown in Figi,Jrt J4>page 1 4. This
ai J. ows m01,11lting r.be aut.omatic ait Vtorand dpatts i(,o tank
off of the s<poararor .
In sta ll re li ef va lv e
L ln.stalJ t<litf val"" ONLY assbown inFigut. 12.
1. Connect discharge piping 10 safe di .. ~pus · aJ IOGi ti on •
tb llow'i ng guiddblt<-$ in Figure 1$, pt.~g-e-13 .
Figure 12 Install and pipe relief valve
( 4}~,.\i j®
.. , ,.....
.. " r
j·
r
'
.....
Legend
)atlo.-tplug fclr unused rcllefV' oli\' t Jackt "~"''"'
lng.
2 fad<tls alt. proVIded W!U r t W6 re lief valVe op6i-
i . n gtb.:c:au.~racl 1 jad:et $'iU: i ti,I;Sed for tw obOtltr
$ius. -C/J\'<r the unu>«i optnln .g Wid> the plug
rn:rvtclt<L
3 Bo il er relid'\'liiV< (from ll«c$$Ory bag)
4 '4" x3 •• n i ppl~. provided in acccssory - bag
5 ~·· fditf vah't tapping inback .$b:ti<>n
6 Connect min1mw'n 1i ,. c,l.ilicharg'e plp. ing to rdid'
\'31\'C,
S.. flgur•1 3, pogoo 13 .
r..art nwuberSSO-l42-7iU/IOil

GV90 + Series 2 OAS·FIRED WATER BOILER - Boiler Manual
Install water piping (continued)
Figure 13 Reliefvalve installation guidelines
IAwARNIN61
Toavoid w.-rd•m•ge or acalclng
du• to relief VIIYe op•mlon, • •
per loc•l or s t.te codM- :
Discharge li ne must be con nected
ro rt li ef valve outlet and run ro a
safeplace of disposaLTermi na te the
discharge li nt in a man n er that will
p ~ • t tn t poss ib il i ry of severt bums
or pr optrty damagesho ul d r. he \'ll ] vt
disdlarge.
Dischar ge line must be as short as
po ssible and be r. he same si r.e as the
\~vt dischargeconn ec ti on r. hrough-
out itsentirel engr. h.
Dischargel
in emustpitchdownward
f'rom the valve and tenn in art at least
6' above the floor drain where any
discha rg e will bt dearly vis ibl e.
The discharge line shall termi na te
plai n, nor th read ed, with a mare-
rial
se rviceable fo r temperatur es o(
37 5°F Orgrt:ater.
Do n ot pi pt the discharge ro any
place where (reez in g couldoccur.
No shuroft' va lve sha ll be insra ll ed
betweton r. he relief valw and boiler.
or in the di scharge line. Do n ot
plugor pl ace anyobst ru ction in the
discharge li ne .
fur theoperati on or r. he \'al ve after
filling and pressurizing system by
l ift ing r. he l e• ; er . Ma kesure r. he valve
disdlarges flffly. If !h e vah'f fa il s to
Opt- rate corr ectly, repl ace it with a
ne-w rf'l i ef va h· e.
Fa il ure to comply with r.he above
guidelin es co ul d resu lt in failure or
r. h t- rf'l i ei' \•alw to optnate. r es ul t in g
in possib ili ty of se\· e: re person al in-
ju r y, d ear.h or subsrantial property
da.mage.
Part n um ber 55 0- 14-2 -783/1012
E xpa ns io n tank
Fi gu re 14. page 14 and Figure 15. page 14showtypical insra ll ation of the
expansion tank. Al way$ locate r. he air separator and expansion tank as
shown in r. hesuggestedpipingdrawings. beg in ningwi th Figure 17,page 16.
Ensure r. hat the expanslon tank size w iJI handle bo il er and system water
volume and temperatu-re.
Set' tank manufacturer's instructions and rat-
i
ngs fo rdetai ls. Add iri ona l ta nks may be added to the sysrem if needed ro
handle
th eexpansion. Th ese ranksmay be insta ll ed byconnecting r.o tees
in
r. hesystem pipin g.
UndeniZCid expansion tankscausesystem ware rrobe l os t
from th er.tli ef \'ll l ve and makeupwater to be added th rough
the fiU\•ah-e. E\'entual section fallucecan resul t. Always locate
th ecokt water flllconntcUonat theexpansion tank. Never
locate thiselsewherein thesystem.
Diaphragm· or blaclcler-type tank:
Refer ro Figure 14 , page ·14 fo rsuggest ed piping when usinga diaphragm-
or bladder - type expansion tank.
NOnCE
Diaphragm· o.- bladdor·typtexpansion tank-Control
flU prNSU'e wi th th erankairchar ge pressure.Alwaysched::
pressure a~nd char ge tank with tank removed from sy.tem
to be sure r e:ad ing is accurate. Bo iler reli ef \oalve is serfor 30
PS I G. Operatingpressure of system.aftertemperaturt expan -
sion abo\ -e cold fill pressure , should not exceed 24 PSIG to
avo id weepingofre li efva h· e.
Insta
ll an automatk air wnt on top of th e air separator, per separator
manufacturtr 's instructions.
Closed-type expansion tank:
Fi gu re IS,page 14showssuggestedpiping when usingadosed-typeexpan-
sion tank, in which th e air isd ir tctly in contact with rank warer.
Connect piping (Y:t,. or ·W') from the air separaror t op outlet ro r. he tank
fitting. Slope any horizontal piping a minimum of t inch per 5 feet of
ho ri 1..0 n ra l pipe.
Always use a tank fitting. such as th e B&G Tnnk-trol or Taco Taco -T ro l
( shown ).The fittlng reduc esgrav ity flo wof wa te r In the plplng to the tank,
a>'oids air bubbling the <>Ugh the tank wa te r, and pro v ides the proper fill
heighrin th e tank.
NO TICE
COI'I"eCt aU leaks in the system or tank pip in g. le:aks alloo.v-
air ro escape from thesystem and will cause water-logging
of th e tank.This wi ll result in waterloss r.hrough th e boiler
rdiefval
v.e due roover-prtssuri:zarion.
NEVER use an automa ti ca ir venr inasysttmequippedwi th a
dosed-type-expansionrank. Theair ~moved from rhesystem
will cause wa ter-l oggi ng of theexpansion tank.
Cl~type expansiontank- Follow tank man ufac[Uru's
instructio-ns for
ftUk'lg the tank.Typicaltank si'z: ing provides
for appr<>Ximately 12 PSIG when the tank is fill ed to the
normallevel andsystem water i.s co ld. Note that boilerre li tf
va lw i.s se ·t for 30 PSJG. Operating pressu re of sysrem. after
t ern peca ture expansion abo\'e cold fill presSW"e , should not
excttd 24 PS IG to a\ro id wetping of reli ef vahre.
13

GV90+ Series 2 OAs-t'IRED WATER BOILER - Boil er ManuaJ
Install water piping (cononuedJ
Figure 14 Pip ing to single-zone system using di ap hr agm · or
bladdllf•lype expansio ntank. Boiloc co nn ectio ns are
1" N PT (s u ppty fr om 1"tee, re tu rn to 1 "' recuperator
Fi g ur e 15 Pi ping closed-type expansion lan k
®
t
NO n CE
Pipe diaphragm - or blad de r·l)'peexp ansio n rank.s to the bo t·
tom of the separator.
NO nCE Pipedosed-
type (air in contact wi th water) tank.s to the topof
theairseparat or. Al v. a ys co nn ect the fill line to the ex pan sion
tank I OC'<ltion , as sh ow n abc we an d in the suggested piping l
t4
Le ge nd
1 Rtli
ef vah·e discharge pip in g- stt- page t2
2 Isol
at ion \<a l \'d
3 F iJI valve
4 Di aphragm - type txpanston tank- al ways locate as
s how n in th esuggesttd pipi ng draw i ngs in this manual
5 Airseparator
provide with automatic ai rwnrONLY when used
with diaphrngm -typtexpansion ranks
pi pe ai roudetto expans ion rank whe n used wi th
dOS< - I)'pe UUlk.s
8 Cold Jill l in e.With . ba c~owpteventerilr Ch eck va lve
wb,..
rtqu i ted by c<ld••t<et Figute 15 foi typioil cOm-
pi\lll'lit ~)
7 S'r•l= .u~plyp i ui n $
8 $ys\o:m n;wro piping
10 Pf clsWe i'ed ll cing va lVe
1
wh.m USc~
11 Quk - k>Jill b)'lll>ss val ve ,wbel) u sed
12. C IU<M- cyl"' E'ltj>I'>Ml6o ranlt- alw oys !o.:a~e o.< Slwwu
i ll the :~ ugg esctd piphl8 d.rawiqp iu thi5 manua l
13 Tank fittlng

GV90 + Series 2 OAS·FIRED WATER BOILER - Boiler Manual
Install water piping (continued)
S ys tem wa te r piping me thod s
NOTICE
Most pi ping methods shown in th i.s manua l u.se
primary/secon dary con necti on to the bo il er l oop .
These designs ens ur e proper flow through the
GV90+ boiler, for the mo st effkient and reliable
opr r ation of the bo iler and Lh e heat i ng syst em.
Fo r othe rpiping methods> consultyourlocal We ll-
McLain r tprtktltath •e.
Ci rcul a to rs
IAWARNING I
Do no tremove either of the GV90+intern al pumps
for u.st elsewhere in the system. Both pumps art
rtqu - irtd for pr ope r operation. Remo\•ing a pump
w ill cause the bo il er to malfunction. Subsrantial
pr operty damage cou ld result.
Ntver Install another pump In .. -. wtth the
GV90+ bollcw . Forced flow can cause improper op-
erarioon of rhe boilercontrols.Substantial pr ope- rry
damage could rtsult.
Fa il ure to comply co ul d result in u nre- li ab le ~rfo r
maJKe and nuisance shutdowns from insuffident
flo w.
Circulatorflow rate
Size systemc.irculatorsbased on the flow rate required to ac.b..ieve
r. he temperature change needtd. You can closely estimate tem -
perature rise (or
drop }throu gh a circuit by using rhe foll owi ng
formula, where TD is temperature rue (ordrop), FLOW u flo w
rate (ingpm).and BTUH is the hearload fo r thecircuit:
FLOW =
BTUH
TD X 600
Examplu :
Consi der a sys tem loopfora systemwith rot:al heatingloadequal
to 210,000 Btuh. Tb e desir<d temperature drop throughthesystem
piping is 20'F. Then the required flow rate is:
210,000
FLOW = =
21 gpm
20x 600
SIMPUREO: For 20" IOJTC)oraturo drop, FLOW • MBH /10.
Circulator head requirement
Th e circulator mUISt be capable ofdelivering the required flow
against the head Loss that will occur in the piping. Dt-termi ne
r. he pipe si te needed and r. he resultant head loss using accepted
engineering method
s. Th e slmp llfied pipe ~z.ing here is limited
roresidential systems.anddoes n
ot includesystems with fan coil
units or radia nt tub ing.
I AcAumN I The following sim
pUfied method for pipe and cir-
cuJaror
si:z: ing must be li mitedroresidentialapp li ca -
tionsusingba se board(finned or cast iron),cast iron
r adiatOrS or COn\rtctors. DO NOT apply for radtant
heating.
f.m coil uni rs orcommercial installations.
Part nu m ber 55 0- 1+2-783/1012
Simplifie d pip e/c ircul ator se l ect ion
t. lns ra ll r. hr bo il erandpipingusi ng therecommended piping
layou rs in r.his manual.
2. Site r. he pip ingandcompontn rs foreach circuitin rhe space
heatingsystem
usi ng Figure- 1 6. At the flow rates ls ted, the
head IOOoSin all piping wtll bo0.041oot per foot of piP<>-
a. Dettrmi nt r.he heating load (Btuh) for each circuit.
b. Calc.ulate the flow rate f or each drc.uit using its load
To usea 200F temperatu re drop, justdivide rhe
MBH (I ,OOO's ofBt uh) by 10.
Exampl
e- Fl ow fo r 20'F tempdr op with 35,000
Btuh: FLOW=
35 MBH I 10 = 3.5 gpm
c. Find the pipesite in Fi
gu re I6 that ha s a max flow rate
just largerthan th ar required for the circuit.
d. Find r. he t:Otal equh ·ale nt le n gr.h (TE L) oftht circuit.
TEL accounts for losse s through 6ttin(!' and valves by
using the equivalent length of pipe r.hat would cause
thesamehead loss. Add tllese nu mbersro rhe measu~d
length of the circuit to find TEL in feet .
TEL Is usually_ close to 1.5 times the length of the
circuitforresidential baseboard,radiator or convec·
t or applicstions.
e. Measure- r. he ltngth of each circuit from rhe circulator
ou d et bsdc to i rs inl et. T he n muldpl) • this l ength times
1 ..5 to ger tht approximate TEL of thecircuit.
f. Find r. he head loss fo reach circuit:
TEL • 1.5 X Circuit Length (feet)
HEAO•
TEL X 0.04 (feet wate< column)
g. NOTE.: Siu sy stem """der piping for the total flow of
aUconnected z.ones.
3. Example:
a. Fo r a circuir with heating l oad= 45,000 Btuh (= 45
MBH). Measur<d length of ci rcuit is 88 fffi.
b. Flow= 45MBH / 10 =4.5gpm.
c. TEL= 1. 5x88 feet = 132 fe.t.
d. From Figure 16, seifct I" pipe (max flo w= 8 gpm).
e. Headloss = T EL x 0.04 = 132 x0.04 = 5.28 fe.t.
f. Selecr a circul ato r that can deliver ar least 4.5gpm at a
head of 5.28 fee L(Read theNOTICEbelow.)
NOnCE To use this method, limit the flow tbrou3:h l4"
finned-tubebaseboard to 3.9 gpm,or use I base-
board
and limit flo wto7.1gpm. If the total load
of thec.
irc.uit requires more flow ,split the drc.uit
into
cwo or mort .
Figure 16 Flow rat es tor 0.04 fMt hfHid Joss,.,-footof
<:Opper pi pe (based oo water at 140"F)
Pipe size
MAX-- (G Pt.l)
Pipe size
MAX-- (G Pt.l)
(lnctoas) • 0 .04 ... per loot (l nctoas) • 0 .04 ... per loot
~ 4 2 45
1 8 :lli 75
1 14
I 14 3 140
11\
22
• 290
15

GV90+ Series 2 o.Ali-FIIIW WATia IIOILER - Boiler Manual
Install water piping (contrnued)
Figure 18 Zq n ~ vallle zoni ng- GV90 +3, GV90+4 or GV90+5
(DO NO Tapply to GV90 +6)
, ··- ·· - -- ··-
I
1 r--- ~ --- ·
\ ... 1-, -"- --
'
I
L (ZiY 103U• t• u li ~ .liVI h l - - " - •· - ·• - •·'I
~ ~
Zone 3
---- ~ ----
I
L lZCfle 2 Clrctl !l P-!Vl fl l - .. - '"l - ... - •• I .. i
Zone 2 1
L ~Zona1o-rWfl~&ml _ .. - .. -.. - ·· ._,
Zo ne 1 I
I
®~ ~ -------------4
'
I
I
•
I •.:fl
: : !_ F
' ~ - -- - - --~ ~ 1 - ---
f
ff_t '
.... .. _,- ·-
Legend
I Isolation'ildvet • Zo n ew l ft
2
Aolomalk air 'lftlt (with 7
Hose bibb pu.rse va lw
di aphr~m-typt ~ n -
8 Boile r prtsswt/~tmptn.·
lion u ).orconn«:t 10
ta.nk 6tuog (d oted-rype
"""8'"8'
ex; pantion tank). 10 Difft:rentia l pttsswt br·
' DUpbra&m·
or bbddtr-
putva lw
ty~ af:n sion tllnk, if
16 Cold watet fi.D line- 8t'lt'!
uud. ( r dosed·typt
Fisure IS, page U for
~ion tl.nk.pipefrom typicdcomponen
tt
to ~ p of a.tr upua tor to
u:nk fiu.ins u in Fi s·
UJ'It 15 ,f!t8t 14 .)
Pipe sizes (NPT), minimum
Bol l or model
Mains Circuits
GV90+3
1'
14'
GV90+4
GV90+5
1l4' 14'
NOTICE
Circuit requirements
See Flgure19
One-p lpo <1 - - systoms -T he ap -
p li cat i on i nfor m ation on this page is based
on tw o- pipe baseboard sys tems. To check
\vhethe:r the internal circuJaror can provide
suff'ic
ient flow to a one -pipe div erter tee
sys rem> u se the a\'llilable head value given in
Figure 19, page 17 .
Figure 19 1h es yslam m ~ meetlhe tollowing r equ irem6f"lts when applyi n ~;~ Fig ur e 18
Bo<ief Ql rculalor HEAD Maldmum 'M1n l mum load Max f&el baseboard Summary
mode l avallabls 10 the clr cutt number ofany of any circuit
S\'S l O<Il longll\ oto lrcults circuit (0 600 BWMoot)
L
e, .o ~eot "" "'
6.5GPM 1018 1
t3V90+3 0 6.SGPM 103lt!el 40MBH 67 feel (max 4 GPM anycirculi)
20'F
4- .1feet w. c.
9. 7GPM 1018 1
GV90+4
Ill 9. 7GPM
92feo l 3 33MB H 55 feel (max 3.3 GPMany clrcuh)
5.5 loti! "' ""
6.7GPM
, QV9(H.S•
08 . 7GPM
f1~lilat 3 53 MBH eo feel (max 3.5 GPMany circuit)
30'F drop
f,ln numberS50-l4:l-783/ l011 17

GV90+ Series 2 oAs·FIRED WATER BOILER - BaUer Manual
Install water piping (cont in ued)
Sin gle -zo ne rad '-1 1 healin g or hea l pump
Radi anr heating sys tems and heat pump systems usuaHy require.
system supply war:er temperatures below 1400F. But theboiler Ol,it.leL
water temperarure will be at least I SOOF to 1600F dur ingmostopt.rot-
ingconditions. So thepiping must indude a method of r Mudng the-
supplywatertemperature to rhesystem.
Figure 22 uses two 'balancingval ves lO manua ll yadjust rht supplyWiiltr-
rtmperaturt. Follow theinstructions ~ l ow toadjustthesevalvts.huuU
thesuppt)•temperature li mitcontrol(irtm 14 ) as showntoprotect tht-
sys tem from over-temperature conditions. Norealso that this piping
requiresa separatesystem ci rculator, as shown> because of the hjgh n-
fl ow ra t es ofradlantand beat pump sys t em s.
Manual adjustment of the supply temperat u ~ is lim it ed to single-
zone systems because mu lti-zone sysrems will cause vary in g ! (load$.,
making it un li kely an acceprable valve setting could be found. See-
Figure 23, page 20 or Figure 24, page20 for multi- 1.o nesystems.
You mayalsoapply thesuggestedpiping of eir. h er Fi gu re 23> page20 or-
Fig ure 24, page 20 if youwanrauromaticsuppl )• temptralure regulation
oroutd oor reset rempt r aturt contro l.
Foradditionalinformationandaltemativtsin pipingforradiant hc:a t-
ingsystems> con tad. \Veil -M cla in.
J /IOTIC E 1 Tho system circulator ,...,t bo supplied by tho In·
stall«.
Adju st bal anc ing va lv es
Use \•alves 17 and. 18 to mix bo iler supplywater with sys tem return
water, reducingsu. pp ly ware r temperarure ro thesysrem.
I. Subrract the design system supply rempe:rature from 1 50°F. Ca U
rhis number rbe temperature dtffennce .
2. Open val v< 17 and do,. va l\· < 18 .
3. Starr the bo il er and system.
4. Let the sysrem warm up f'o rabout 15 min ut es.
5. Note the temper atu re ar gauge 9 (sysrem supply) and gauge 8
(bo il ersupply).
6. Slow ly dose \-alve 17 whileopening \•alvt 18 unr ll gauge 9 1't'"Jd !
towerth an gauge8 byar leastthe temperature dtfferenc• fOund
in ~t<p I.
1. Example: Fo ra desi gn supply temperat u ~ of 100°f, r. hetempera-
turedtfferenc.e
wo Ul d be I SOOF minus IOOOF .or SOOF. Se t the vn.J\ftl
untilgauge 9 readsat least SOOF lowerthan gauge 8.
Part nu m ber 550-1+2-783/1012
Figure 22 Si n g!e. · zo na radi~t heating or
h eat PUII\P sys t om
"'
ot'
jo a ""' .,-,
"
01/90+
"'""
Lege11d
1 Isolation T&h'el.
2 A·utomaric air vrnttwilh diapfU'BJPll ·fl'F't apa u Sioll
tank .) , or oonnec uo tank,fitting (dose d-type . e:xpa n·
s.ioncank l~ I
3 ~i.ap.h.rayn· or bl adthec-typ t: exF*~.Oo t¢k
1
i. (l.!Sed
(F'or d asti! · t)~exp an · sion tank. pi p¢ fm.rn topofilir
sep~.mtort o tarik 6ttingasiittf.lgurt 15~ pagt 1 4. )
5 S)?tt:mcirtu:b.tor
7 H nSt" bi bb purg.e:Ya.h-e
fl IRHierr ~e( t e:mpc-rarure gauge-
~ Systt:m s u pP l ~ te ru pen1twl!g:.uge
10 R~tu.rn. rem pt:rof\l.fepu~
14 ~ Upplyfempt:r am r~ Umitconttoi-Sd:'!lt'9 U!mpe:ra-
tu rtbtklwth¢ max imum 'Ill~ for the 'Ylll<!'m orIll
directed bythe-n•sttm Wig:ner .
16 Co l dwar;er 6U line- seef igure ts~pagelA forrypfca l
compa.n~nn
17 Ril..l ando_g vai"Vt>.
'! S. l """"g""' = "' !:.----------.!
19

GV90+ Series 2 oAs·FIRED WATER BOILER - Boiler ManuaJ
Install water piping rconunuedJ
Mult i- zone rad ia nt heat i ng system
Mu lti-zone systems req ui re auromatic regulation of the s y st~m sup-
ply temperature becau.se of wi dely va r ying load co nditions. Figure 2.3
(zone- \-a l ve roning) and Figure24(circularorzoning)showsuggestfil
piping for thesesysrtms.
I AWARNJfG I Provide an automat ic temperature control valve or
moto r-Optr.ued va l ve \vhich can be adjusred fo r the
desired supp l)• water t tmpt r atu rt . This is required tn
protect the radi ant system from excess i ve temperarure.
Zone-valve
zo ni ng- The sugge sted piping uses aseparate ci rculatot
for sys tem circulation to provide the hlgh er flow typical of radian t
heating S)'Sttms and to assure good temperature di.srri buri on in the-
s ys tem whe n the rttu rn watertemperature is l ow.
Circul .aro r zo ni ng -The GV90+ internal ci rculatorS must n ot be-
remo,red. Providea separat~ circul atO r for each 7.0 n ~ .
I NOTICE
NOTICE
NOTICE
NOTIC E
Baianc lr).g, when *"'lnKI -Substitutea memory-stop
val\ · ~ for one of the isolation valves in each z.one ro usc
the memory-stop v ah-e for balanc.ing flow as well as
isolarion_
Zoning wtth zon• valves-Provide a separate24-voiL
transf orme r to power the zone valves. Size the trans-
former to hand le the total rated load of a ll conne.: ted
zone vah r es. A lt ernath<e l y, use a 20 ne va l ve 20ne contro ll er .
Do not LIMR& C coi'WMtCdons for zonev al vt.
Zoningwtth circulaton -TheGV90+internal sysrern
circulatOT cann ot be removed from rhe bo il er for use as
one of tbe zone circuJarors. lr must remain asshipp ed
from the fa ctory to allo w proper fl ow contr ol ins ide the
bo il e r. You w ill n ~ a circularor for ~ach zone. Provide
circulatOT rela ys or circul ato r zone contro ll er. The sys-
tem clrculalor must be supplltd by the Installer.
Outdoor reset
App lyFigure 23or Figure 24 forany system inrended forourdoor rtsel
of thesupplywater remperaturt. Use amotor-operated th ree-wayvah re-
and an outdoor reset temperaturecontrol sy stem.
20
Legend
Lsolatfon vatves
2 A ut oma t ic air vent (w ith diaphragm - type expansion tank)~ or
connect to tank 6tting ( dosoecf-type expansion tank ),
3 Diaphragm- or bladder.rype expansiont ank. if used ( For closed-
typeexpansion
tanlr. pipefromt o pofairseparatortotank fitting
as in Figure l~pa~ 14 .)
4 Zone val\>e
5 System or zone ci.rc uJ ato r
6 Flowlch eck val ve
7 Hose bibbpurge vah-e
8 Boiler pressurelt emperarure gauge
9 System sup pl yt emperature gauge
10 Supplytemperatore auto matic mixing vaJ,-e
I I Differential presswe by-pass vatve
16 COld ,ater6Uline -see Figure l~page 14fortyptcalcomponents
Figure 23 A~to sys te m "'1PPiY temp regulation-
zooo valva ZOflt ng
... ~ - .]. - •.zonol -- ~ - ~ "t
I <::I I
Zon•"
-
¢1
Q
:~
1'
••
19..)
0
•t_t\t
0
'!\
r;o.
c:>
1
~ ~
~·
...
"'
'll
-·
0 Q
" ' t ~ .
OV90 ._
I
Figure 24 Autosystem supply temp reguiat iQO -
ci rculatorzoning
... ~ - .,. _
I
.,.
--
t,!::
0
r
£:>
ll
\I
ZOn.G 2
~ "' - ~ - + ..
Q
Zona 1
¢3 -
ri
· ~
:f#
~: (?o
• X
@{
·~.
GV90•
I
I
<::1
T 0
· ~
!~
95 1) 1 Bb
Pan n um ber 5SO.I<t2-783110l2