New Yorker AP-U SERIES Service manual

INSTALLATION, OPERATING
AND SERVICE INSTRUCTIONS
AP-U™ SERIES
STEEL OIL-FIRED BOILER
8147101R5-3/08 Price - $3.00
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2
The following terms are used throughout this manual to bring attention to the presence of hazards of various risk levels,
or to important information concerning product life.
REGNAD
noitautissuodrazahyltnenimminasetacidnI
,htaednitluserlliw,dediovatonfi,hcihw
ytreporplaitnatsbusroyrujnisuoires
.egamad
GNINRAW
noitautissuodrazahyllaitnetopasetacidnI
,htaednitluserdluoc,dediovatonfi,hcihw
ytreporplaitnatsbusroyrujnisuoires
.egamad
NOITUAC
noitautissuodrazahyllaitnetopasetacidnI
etaredomnitluseryam,dediovatonfi,hcihw
.egamadytreporproyrujnironimro
ECITON
,noitallatsninosnoitcurtsnilaicepssetacidnI
erahcihwecnanetniamro,noitarepo
yrujnilanosrepotdetalertontubtnatropmi
.sdrazah
IMPORTANT INFORMATION - READ CAREFULLY
ECITON
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dellatsniyltcerroceraslortnocllatahteesotrotcartnocgnillatsniehtfoytilibisnopserehtsitI
sireliobsihtrofytnarrawehT.etelpmocsinoitallatsniehtnehwylreporpgnitarepoeradna
esehthtiwecnadroccanidetarepodnadeniatniam,dellatsnineebsahreliobehtfiylnodilav
.snoitcurtsni
,gnibmulPlacoLdnaetatS,lanoitaNhtiwecnadroccanidellatsniebtsumsreliobllA
sedoCesehT.seitilitugnivresehtfosnoitalugerehtdnasedoClacirtcelEdnagnitaeH
gnivahseitirohtuA.launamnoitcurtsnisihtmorfreffidyamsnoitalugeRdna
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:sdradnatSgniwollofehtotedamebdluohsecnerefer,sesacllanI
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.secivedytefasdnaslortnocfosnoitarepo

3
REGNAD
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.ecnailpparehto
GNINRAW
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redroreporpehtnisnoitcurtsnillawollofoteruliaF.efilfossolroyrujnilanosrep,egamad
llagnidulcni,snoitcurtsnilladnatsrednudnadaeR.htaedroyrujnilanosrepesuacnac
ehthtiwdedivorperahcihwslaunamsrerutcafunamtnenopmocnideniatnocesoht
.ecnailppasihtgnicivresrogniniatniam,gnitarepo,pu-gnitrats,gnillatsnierofebecnailppa
ecnereferrofecnailpparaendetsopdnanoitidnocelbigelnierutaretildnalaunamsihtpeeK
.naicinhcetecivresdnarenwoyb
ehtwolloF.ylefasetarepootecivresdnaecnanetniamralugerseriuqerreliobsihT
ebtsumecivresdna,ecnanetniam,noitallatsnI.launamsihtnideniatnocsnoitcurtsni
llA.ycnegaecivresrorellatsnielbaegdelwonkdnadelliks,decneirepxenaybylnodemrofrep
snosrepylnodnasrotcartnoctnetepmocybdengisedebdluohssmetsysgnitaeh
tpmettadluohssmetsysgnitaehcinordyhfonoitallatsnidnatuoyalehtnielbaegdelwonk
llatahteesotrotcartnocgnillatsniehtfoytilibisnopserehtsitI.reliobynafonoitallatsni
.detelpmocsinoitallatsniehtnehwylreporpgnitarepoeradnadellatsniyltcerroceraslortnoc
detacolgnippatehtotnidellatsnisievlavfeilererusserpasselnuetelpmoctonsinoitallatsnI
.sliatedroflaunamsihtfoIIInoitceSeeS-ecnailppafopotno
ahtiwdellatsnisselnu,gniroolfelbitsubmocnonoitallatsnirofelbatiustonsireliobsihT
.)tsocartxetaelbaliava(dleihsroolfelbitsubmoc
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otnosaesgnitaehehtfotratsehttaylbareferp-raeyaecnotsaeltadenaelcsebuteriFevaH
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.emitemasehttadetcepsni
.detatissecenebyamsaroraeyaecnotsaeltadekcehcslortnoCdnarenruBliOevaH
.secivedytefasroslortnoctnesbaroderepmujhtiwtinuetarepotonoD
.retawottcejbusneebsahecivedro,tnenopmoc,hctiws,lortnocynafitinuetarepotonoD
,animulaniatnocleufehtdnanoitsubmocfostcudorp,noitcurtsnocfoslairetamecnailppA
rocixotrehtoro/dnasedyhedla,sedixonegortin,edixonomnobrac,slatemyvaeh,acilis
ehtotnwonkerahcihwdnayrujnisuoiresrohtaedesuacnachcihwsecnatsbuslufmrah
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llA.)PL,saglarutan.e.i(leufsuoesagynaottrevnoctonoD.)laoc,doow.e.i(leufdilos
.semitllatareliobehtforaelctpekebdluohs,.cte,sparcsdoow,repap,sgar,sirbedelbammalf
.sdrazaheriffoeerfdnanaelcaerareliobehtpeeK

4
Table of Contents
I. Pre-Installation...............................6
II. Knockdown Boiler Assembly..........9
III. Water Piping and Trim .................12
IV. Venting.........................................17
V. Electrical.......................................19
VI. Oil Piping.....................................22
VII. System Start-Up............................24
VIII. Service and Cleaning .................... 33
IX. Repair Parts..................................35
X. Beckett AFG Burner Parts for
AP-U™ Series Boilers....................38
XI. Riello Burner Parts for
AP-U™ Series Boilers....................40
XII. Appendix
Low Water Cut Off .......................41
GNINRAW
,acilis,animulaniatnocleufehtdnanoitsubmocfostcudorp,noitcurtsnocfoslairetamecnailppA
lufmrahrocixotrehtoro/dnasedyhedla,sedixonegortin,edixonomnobrac,slatemyvaeh
ainrofilaCfoetatsehtotnwonkerahcihwdnayrujnisuoiresrohtaedesuacnachcihwsecnatsbus
,gnihtolcytefasreporpesusyawlA.mrahevitcudorperrehtodnastcefedhtrib,recnacesuacot
.ecnailppaehtybraengnikrowrognicivresnehwtnempiuqednasrotaripser
ronsgnittifepipynawercsnutonoD.serusserphgihrednuretawtohyrevsniatnocreliobsihT
loocsiretawehtgnirussaylevitisoptuohtiwreliobsihtfostnenopmocynatcennocsidottpmetta
pugnitrats,gnillatsninehwtnempiuqednagnihtolcevitcetorpraewsyawlA.erusserponsahdna
erutarepmetdnaerusserpehtnoylertonoD.seirujnidlacstneverpotreliobsihtgnicivresro
stnenopmocsniatnocreliobsihT.reliobehtfoerusserpdnaerutarepmetehtenimretedotseguag
yehtsselnustnenopmocynahcuottonoD.gnitareposireliobehtnehwtohyrevemocebhcihw
.loocera
doognimetsystnevdevorppanaotdetcennocdnadetnevylreporpebtsumecnailppasihT
tnevdevorppanunaotdetcennocsireliobehtfitluserdluocegamadytreporpsuoireS.noitidnoc
.metsys
rofsnoisivorperaerehtosdellatsniebtsumdnanoitarepoefasrofriahserfsdeenreliobsihT
.rianoitalitnevdnanoitsubmocetauqeda
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ynarofnosaesgnitaehehttuohguorhtyllacidoirepdetcepsniebdluohsdnanosaesgnitaehehtfo
wollaotyrassecenerasmetsysekatniriadnagnitnevdetcurtsbonudnanaelC.snoitcurtsbo
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.ycneiciffes'reliobehtgniniatniam
trats-ertondnanwodtuhsotreliobehtesuacyamhcihwslortnochtiwdeilppussireliobsihT
dluohsmetsysgnitaeheht,ytilibissopasisepipnezorfoteudegamadfI.ecivrestuohtiw
dellatsniebdluohssmraladnasdraugefasetairporpparo;rehtaewdlocnidednetttanutfelebton
.evitareponisireliobehtfiegamadtneverpotmetsysgnitaehehtno
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dilosynaottrevnoctonoD.reliobsihtnirepaproegabragnrubreveN.enilosaggniniatnoclio
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naelcaerareliobehtpeeK.semitllatareliobehtforaelctpekebdluohs,.cte,sparcsdoow,repap
.sdrazaheriffoeerfdna
revoetercnoC.dleihsroolfdeilppusyrotcafatuohtiwroolfelbitsubmocnoreliobetarepotonoD
yamhcihw,sroolfyrnosamnoetarepotonoD.gniroolfelbitsubmocderedisnocsistsiojdoow
.erutsiomniatnoc

5
Figure 1: AP-U Series Boiler Dimensional Data
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U097-PA '51x"7 4.51 553

6
A. INSPECT SHIPMENT carefully for any signs of
damage.
1. ALL EQUIPMENT is carefully manufactured,
inspected and packed. Our responsibility ceases
upon delivery of the crated boiler to the carrier in
good condition.
2. ANY CLAIMS for damage or shortage of shipment
must led immediately against the carrier by the
consignee. No claims for variances from, or
shortage in orders, will be allowed by the
manufacturer unless presented within sixty (60) days
after receipt of goods.
B. LOCATE BOILER in front of nal position before
removing crate.
NOITUAC
tekcajreliobpmubtonoD.reliobpordtonoD
.roolftsniaga
1. LOCATE so that smoke pipe connection to chimney
will be short and direct. BOILER IS NOT SUIT-
ABLE FOR INSTALLATION ON COMBUSTIBLE
FLOOR unless combustible oor shield, supplied by
New Yorker® Boiler Co. Inc., is used.
I. Pre-Installation
DO NOT install on carpeting. See Figure 3 for oor
shield part number and installation instructions.
2. FOR BASEMENT INSTALLATION, provide a
solid base, such as concrete, if oor is not level, or if
water may be encountered on oor around boiler.
3. PROVIDE SERVICE CLEARANCE of at least 48”
from the front of the jacket for servicing of burner
and removal of tankless heater.
For minimum clearances to combustible materials. See
Figure 2.
GNINRAW
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yamhcihw,sroolfyrnosamnoetarepo
.erutsiomniatnoc
Figure 2: Minimum Clearances to Combustible Materials
NOTE:
1. Listed clearances comply with American National Standard ANSI/NFPA 31, Installation of Oil Burning Equipment.
2. AP-U™ boilers can be installed in rooms with clearances from combustible material as listed above. Listed clearances can
not be reduced for alcove or closet installations.
3. For reduced clearances to combustible material, protection must be provided as described in the above ANSI/NFPA 31
standard.

7
C. REMOVAL OF BOILER
1. Move boiler (in carton) to installation site as close
as practical.
2. Remove the carton sleeve.
3 Remove four (4) hex head lag screws, attaching
boiler base plate to shipping skid.
4. Carefully, walk boiler to the edge of the skid. Tilt
the boiler back, allowing boiler base edge to rest on
the oor, then, remove the skid.
D. PROVIDE COMBUSTION AND VENTILATION
AIR. Local code provisions may apply and should be
referenced.
GNINRAW
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reporperussaotdedivorpebtsumria
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.serutarepmetriatneibma
roenilosagerehwreliobllatsnitonoD
ro,sdiuqilrosropavelbammalfrehto
,sehcaelb.e.i(snobracordyhfosecruos
rodesuera).cte,srenetfoscirbaf
.derots
1. Determine volume of space (boiler room). Rooms
communicating directly with the space in which the
appliances are installed, through openings not
furnished with doors, are considered a part of the
space.
Volume(ft3) = Length(ft) x Width(ft) x Height(ft)
2. Determine total input of all appliances in the space.
Add inputs of all appliances in the space and round
the result to the nearest 1000 BTU per hour.
3. Determine type of space. Divide Volume by total
input of all appliances in space. If the result is
greater than or equal to 50 ft3/1000 BTU per hour,
then it is considered an unconned space. If the
result is less than 50 ft3/1000 BTU per hour then the
space is considered a conned space.
4. For boiler located in an unconned space of a
conventionally constructed building, the fresh air
inltration through cracks around windows and
doors normally provides adequate air for
combustion and ventilation.
5. For boiler located in a conned space or an
unconned space in a building of unusually tight
construction, provide outdoor air with the use of two
permanent openings which communicate directly or
by duct with the outdoors or spaces (crawl or attic)
freely communicating with the outdoors. Locate one
opening within 12 inches of top of space. Locate
remaining opening within 12 inches of bottom of
space. Minimum dimension of air opening is 3
inches. Size each opening per following:
a. Direct communication with outdoors.
Minimum free area of 1 square inch per 4,000
BTU per hour input of all equipment in space.
b. Vertical ducts. Minimum free area of 1 square
inch per 4,000 BTU per hour input of all
equipment in space. Duct cross-sectional area
shall be same as opening free area.
c. Horizontal ducts. Minimum free area of 1
square inch per 2,000 BTU per hour input of all
equipment in space. Duct cross-sectional area
shall be same as opening free area.
Alternate method for boiler located within
conned space. Use indoor air if two permanent
openings communicate directly with additional
space(s) of sufcient volume such that combined
volume of all spaces meet criteria for unconned
space. Size each opening for minimum free area
of 1 square inch per 1,000 BTU per hour input of
all equipment in spaces, but not less than 100
square inches.
6. Louvers and Grilles of Ventilation Ducts
a. All outside openings should be screened and
louvered. Screens used should not be smaller
than 1/4 inch mesh. Louvers will prevent the
entrance of rain and snow.
b. Free area requirements need to consider the
blocking effect of louvers, grilles, or screens
protecting the openings. If the free area of the
louver or grille is not known, assume wood
louvers have 20-25 percent free area and metal
louvers and grilles have 60-75 percent free area.
c. Louvers and grilles must be xed in the open
position, or interlocked with the equipment to
open automatically during equipment operation.

8
INSTALLATION INSTRUCTIONS FOR OPTIONAL SHIELD REQUIRED
FOR COMBUSTIBLE FLOOR
This shield for combustible oors is intended for use only with the following New Yorker oil-red boilers:
Use Part Number 6183504 for the following models:
AP-490U AP-590U AP-690U AP-790U
ADDS 4-3/16” TO BOILER HEIGHT
1) Place shield on combustible oor with “TOP” surface
upward and “FRONT” surface directly below the
expected position of the oil burner.
2) Locate shield such that clearances to combustible walls
are as indicated in Figure 3. These dimensions will
assure that the boiler jacket will be at least 18” from
the side and rear walls and 48” from the front wall, as
required by ANSI/NFPA 31.
3) Fasten shield to combustible oor to keep shield from
shifting position during setting of boiler.
4) Set boiler squarely on top of shield such that base plate
of boiler rests at on top surface of shield and does not
over-hang shield on any side. Conrm clearance to
combustible walls. Refer to Figure 2.
5) Do not enclose boiler (including shield) on all four
sides. Boiler may be enclosed on any three sides while
maintaining minimum clearances shown in Figure 2 for
each of those three sides.
Figure 3: Floor Shield

9
II. Knockdown Boiler Assembly
Figure 4: Bare Boiler on Skid
Knockdown AP-U Series boilers are shipped as two
separate items:
Bare Boiler Assembly (mounted on skid)
Jacket Carton Assembly
Inspect shipment carefully for any signs of damage.
A.REMOVAL OF BOILER
1. Remove and discard four boiler-to-skid hold down
fasteners. Refer to Figure 4.
2. Carefully walk boiler to the skid edge. Tilt the boiler
back, allowing the base edge to rest on the oor, and
remove the skid.
3. Remove the adhesive backed label-containing
envelope from boiler and set aside.
4. Remove Misc. Parts Bag and bagged Temperature
and Pressure Gauge (both tucked inside canopy
assembly ue collar) and set aside.
Figure 5: Jacket Installation
B. INSTALLING THE JACKET
1. Remove jacket parts and jacket hardware bag from
Jacket Carton Assembly shipping carton.
2. Install the Wrap-Around jacket panel rst. Bend
Wrap-Around panel as shown in Figure 5. Attach
the bent panel to base using three #10-1/2” slotted
hex washer head screws supplied. Engage all screws
but do not tighten yet.
3. Remove 5/16-18 hex nut, 5/16 at washer,
observation cover spring and Observation Port
Cover and set aside.
4. Attach Lower Front Jacket panel to installed Wrap-
Around panel with four #10-1/2” slotted hex washer
head screws supplied. See Figure 5.
5. Attach Upper Front Jacket panel to installed Wrap-
Around panel with four #10-1/2” slotted hex washer
head screws supplied. See Figure 5.
6. Lastly, install Top Jacket panel and secure to
installed Wrap-Around panel with two remaining
#10-1/2” slotted hex washer head screws. See Figure
5.
7. Once installed, center Top Jacket panel opening over
canopy assembly ue collar and tighten up all three
screws securing Wrap-Around panel to base.

10
8. Attach provided New Yorker logo plate to installed
Top Jacket panel with two #8 x ¼ sheet metal
screws. See Figure 6.
9. Remove labels from the adhesive backed label-
containing envelope and attach them to jacket
panels. See Figure 6 for approximate label
positioning.
C. INSTALLATION OF BOILER CONTROLS
1. Install provided Temperature and Pressure gauge
and aquastat well into appropriate tappings; tighten
securely to prevent water leaks.
2. Install provided 1-1/4 x 3/4 reducing hex bushing
and drain valve into lower right hand 1-1/4 forged
coupling ‘drain’ taping.
3. Install provided 1-1/4 x 3” black nipple into lower
left hand 1-1/4 forged coupling ‘return’taping.
4. Mount installer-supplied aquastat onto the
immersion well. Wire the control per Figure 15 or
Figure 16, Section IV ‘Electrical” of the Installation
and Operating Instructions for AP-U Series Oil-
Fired Boiler, as applicable.
GNINRAW
otnidetresniyllufebtsumblubtatsauqA
.lleweht
5. Install provided safety relief valve (for details see
Figure 9.
6. Re-install Observation Port Cover and related
hardware in reverse order to removal. See Figure 7.
Figure 6: Label Locations

11
Figure 7: Burner Mounting
D. BURNER INSTALLATION
1. Insure burner gasket proper t/positioning on burner
air tube, relative to burner mounting ange, prior to
burner mounting. See Figure 7.
NOITUAC
.teksagtuohtiwrenrubllatsnitonoD
2. Mount installer-supplied burner onto base front
panel studs and secure with provided 5/16 at
washers and brass 5/16-18 hex nuts. Refer to
Figure 7.
3. Wire the burner per instructions, provided with the
burner, and, Figure 15, 15A, 16 or 16A, as
applicable.

12
Figure 8: Recommended Piping for Combination
Heating and Cooling (Refrigeration) System
III. Water Piping and Trim
A. DESIGN A PIPING SYSTEM and install boiler which
will prevent oxygen contamination of boiler water and
frequent water additions.
1. There are many possible causes of oxygen
contamination such as:
a. Addition of excessive make-up water as a result
of system leaks.
b. Absorption through open tanks and ttings.
c. Oxygen permeable materials in the distribution
system.
2. In order to insure long product life, oxygen sources
should be eliminated. This can be accomplished by
taking the following measures:
a. Repairing system leaks to eliminate the need for
addition of make-up water.
b. Eliminating open tanks from the system.
c. Eliminating and/or repairing ttings which allow
oxygen absorption.
d. Use of non-permeable materials in the
distribution system.
e. Isolating the boiler from the system water by
installing a heat exchanger.
GNINRAW
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tnaidardnadraobesab,srotaidarllafo
ebtsumgnipipgnitcennoclladnagnibut
.deredisnoc
3. Connect System supply and return piping to boiler.
See Figures 9 and 10. Also, consult I=B=R
Installation and Piping Guides. Maintain minimum
½ inch clearance from hot water piping to
combustible materials.
a. If this boiler is used in connection with
refrigeration systems, the boiler must be installed
so that the chilled medium is piped in parallel
with the heating boiler using appropriate valves
to prevent the chilled medium from entering the
boiler. See Figure 8. Also, consult I=B=R
Installation and Piping Guides.
b. If this boiler is connected to heating coils located
in air handling units where they may be exposed
to refrigerated air, the boiler piping must be
equipped with ow control valves to prevent
gravity circulation of boiler water during the
operation of the cooling system.
c. If boiler is used with an Indirect-Fired Domestic
Water Heater, install the Indirect-Fired Domestic
Water Heater as a separate heating zone. Refer
to the Indirect-Fired Domestic Water Heater
Installation, Operating, and Service Instructions
for additional information.
d. Use a system bypass if the boiler is to be
operated in a system which has a large volume or
excessive radiation where low boiler water
temperatures may be encountered (i.e. converted
gravity circulation system, etc.) The bypass
should be the same size as the supply and return
lines with valves located in the bypass and return
GNINRAW
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13
line as illustrated in Figures 10 and 11 in order to
regulate water ow for maintenance of higher
boiler water temperature. Set the bypass and
return valves to a half throttle position to start.
Operate boiler until the system water
temperature reaches its normal operating range.
Adjust the valves to maintain 180°F to 200°F
boiler water temperature and greater the 120°F
return temperature. Adjust both valves
simultaneously. Closing the boiler return valve
while opening the bypass valve will raise the
boiler return temperature. Opening the boiler
return valve while closing the by-pass valve will
lower the boiler return temperature.
e. A water boiler installed above radiation level
must be provided with a low water cutoff device
as part of the installation.
B. INSTALL SAFETY RELIEF VALVE. See Figures 9,
10 and 11. Safety Relief Valve must be installed with
spindle in the vertical position. Installation of the relief
valve must be consistent with ANSI/ASME Boiler and
Pressure Vessel Code, Section IV.
GNINRAW
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C. AIR VENT. An air vent or purge must be incorporated
in the system to easily remove air from the boiler when
the system is lled. The boiler has a built in dip tube
which works with the air vent to clear the boiler of air.
Improper application of the air vent will cause steaming
in the boiler. See Figure 9.
D. INSTALL DRAIN VALVE in return piping. See
Figures 10 and 11.
E. OIL, GREASE, AND OTHER FOREIGN
MATERIALS which accumulate in new hot water
and a new or reworked system should be boiled
out, and then thoroughly ushed. A qualied water
treatment chemical specialist should be consulted for
recommendations regarding appropriate chemical
compounds and concentrations which are compatible
with local environmental regulations.
GNINRAW
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Figure 9: Air Vent and Safety Relief Valve
Installation Detail
F. AFTER THE BOILER AND SYSTEM HAVE BEEN
CLEANED and ushed, and before relling the entire
system add appropriate water treatment chemicals, if
necessary, to bring the pH between 7 and 11.
G. CONNECT TANKLESS HEATER PIPING AS
SHOWN IN FIGURE 12. See Table 1 for Tankless
Heater Rating.
GNINRAW
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14
Figure 10: Recommended Boiler Piping for Circulator Zoned Heating Systems

15
Figure 11: Boiler Piping for Zone Valve Zoned Heating Systems

16
Figure 12: Schematic Tankless Heater Piping
Table 1: Tankless Heater Ratings
ledoMrelioB
ledoMretaeHsselknaT
4-S 5-S
MPG DISP MPG DISP
U094-PA 3 21 ½3 51
U095-PA ¼3 61
¾3 52U096-PA ½3 91
U097-PA
required by dishwashers and automatic washers is
possible by piping the hot water from the heater
prior to entering the mixing valve. The mixing valve
should be “trapped” by installing it below the cold
water inlet to heater to prevent lime formation in the
valve. Refer to Figure 12.
3. FLUSHING OF HEATER — All water contains
some sediment which settles on the inside of the
coil. Consequently, the heater should be periodically
backwashed. This is accomplished by installing hose
bibs as illustrated and allowing water at city
pressure to run into hose bib A, through the heater,
and out hose bib B until the discharge is clear. The
tees in which the hose bibs are located should be the
same size as heater connections to minimize
pressure drop.
4. HARD WATER — A water analysis is necessary to
determine the hardness of your potable water. This
is applicable to some city water and particularly to
well water. An appropriate water softener should be
installed based on the analysis and dealer’s
recommendation. This is not only benecial to the
tankless heater but to piping and xtures plus the
many other benets derived from soft water.
THE FOLLOWING GUIDELINES SHOULD BE
FOLLOWED WHEN PIPING THE TANKLESS HEATER:
1. FLOW REGULATION — If ow through the heater
is greater than its rating, the supply of adequate hot
water may not be able to keep up with the demand.
For this reason a ow regulator matching the heater
rating should be installed in the cold water line to
the heater. The ow regulator should preferably be
located below the inlet to the heater and a minimum
of 3’ away from the inlet so that the regulator is not
subjected to excess temperatures that may occur
during “off” periods when it is possible for heat to
be conducted back through the supply line. The ow
regulator also limits the ow of supply water
regardless of inlet pressure variations in the range of
20 to 125 psi.
2. TEMPERING OF HOT WATER — Installation of
an automatic mixing valve will lengthen the delivery
of the available hot water by mixing some cold
water with the hot. This prevents the possibility of
scalding hot water at the xtures. In addition,
savings of hot water will be achieved since the user
will not waste as much hot water while seeking a
water temperature. Higher temperature hot water

17
IV. Venting
A. GENERAL GUIDELINES.
1. Vent system installation must be in accordance with
these instructions and applicable provisions of local
building codes. Contact local building or re
ofcials about restrictions and installation inspection
in your area.
2. The AP-U Series is designed to be vented into a
reclay tile-lined masonry chimney or chimney
constructed from type-L vent or a factory built
chimney that complies with the type HT
requirements of UL103. The chimney or vent pipe
shall have a sufcient draft at all times, to assure
safe proper operation of the boiler. See Figure 13 for
recommended installation.
a. Install a draft regulator (supplied by installer)
following the instructions furnished with the
regulator. See Figure 14 for alternate regulator
locations.
b. With any new or replacement installation the
chimney has to be considered. Chimneys that
have a high heat loss become less suitable as the
heat loss of the home goes down and the
efciency of the boiler goes up. Most homes
have a chimney appropriate for the fuel and the
era in which the home was built. That may have
been a coal red or an inefcient oil red boiler
built into a home without insulation or storm
windows. With increasing fuel prices that home
probably has been insulated and tted with storm
windows so that the heat loss of the home has
been reduced. This requires less fuel to be
burned and sends less heat up the chimney.
A new boiler probably has a higher efciency
than the boiler being replaced. That probably
means that the stack temperature from the new
boiler will be lower than that from the old boiler
and with less room air being drawn up the
chimney to dilute the stack gases. The
combination of a large uninsulated chimney,
reduced ring rate, reduced ring time, lower
stack temperature and less dilution air can, in
some cases, contribute to the condensing of
small amounts of water vapor in the chimney.
Such condensation, when it occurs, can cause
chimney deterioration. In extreme cases, the
chimney may have to be lined to insulate the
chimney and thus prevent the condensation. The
addition of dilution air into the chimney may
assist in drying the chimney interior surfaces.
A massive chimney on a cold, or exposed outside
wall may have produced adequate draft when it
was red with a higher input and greater volumes
of heated gases. With reduced input and volume,
the draft may be severely affected. In one
instance our research showed a new chimney of
adequate sizing produced only -.035” W.C. after
30 minutes of continuous ring at 13.0% CO2.
Outside wall chimneys take longer to heat up and
can have .00” W.C. draft at burner start-up. You
may have to consider a special alloy chimney
ue liner with insulation around it and stabilizing
draft cap or even a draft inducing fan in severe
cases.
c. For the same reasons as in (2.) above, heat
extractors mounted into the breeching are not
recommended.
3. For minimum clearances to combustible materials
refer to Figure 2.

18
Figure 13: Recommended Smokepipe Arrangement and Chimney Requirements
Figure 14: Draft Regulator Locations

19
A. GENERAL
1. Install wiring and electrically ground boiler in
accordance with requirements of the authority
having jurisdiction, or in absence of such
requirements the National Electrical Code, ANSI/
NFPA 70, and/or the CSA C22.1 Electric Code.
2. A separate electrical circuit must be run from the
main electrical service with an over-current device/
disconnect in the circuit. A service switch is
recommended and may be required by some local
jurisdictions.
3. Wiring should conform to Figure 15 and/or 16.
B. SYSTEM CONTROLS AND WIRING
1. Refer to National Electric Code or Local Electric
Codes for proper size and type of wire required.
Follow Code.
2. Use anti-short bushings on all wiring passing
through boiler jacket, junction boxes and/or control
boxes.
3. Use armored cable (BX) over all exposed line
voltage wiring.
4. If an indirect water heater is used, use priority
zoning. Do not use priority zoning for Hydro-Air
Systems.
5. Single Zone System – Refer to Figure 15 or 16 for
the electrical diagram for this type of system.
Connect the system circulator wire leads to the
proper locations on the Aquastat control, L7224A/
L7248A. See Figure 15A or 16A. Connect the
thermostat to the ‘T-T’ terminals on the L7224A/
L7248A control. Set thermostat heat anticipator
settings to 0.60 amps.
V. Electrical
GNINRAW
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.ffodenrutsirewopecnokcoldap

20
Figure 15: AP-U Boiler Wiring Less Tankless, Single Circulator w/Beckett Burner
Figure 15A: AP-U Boiler Wiring Less Tankless, Single Circulator w/Riello Burner