Patterson-Kelley MACH 'n' Roll with NURO Series Operating instructions

P-K MACH ‘n’ Roll™with NURO®
CONDENSING INDIRECT DOMESTIC &
POOL WATER HEATING SYSTEM
MnR300-MnR399-MnR500
MnR750-MnR1050 for Indirect
Domestic Water Heating
&
MnRP300-MnRP399-MnRP500
MnRP750-MnRP1050 for
Indirect Pool Water Heating
Part # 1004905989
Model Number:
Serial Number:
Start-Up Date:
Patterson-Kelley
155 Burson Street
East Stroudsburg, PA 18301
Telephone: [phone]
Toll Free: 877.728.5351
Fax: [phone]
www.pattersonkelley.com
Revised: January 3, 2020
INS T ALL A TION
& OWNER ’ S
MAN U A L
INS T ALL A TION
& OWNER ’ S
MAN U A L
INS T ALL A TION
& OWNER ’ S
MAN U A L
INS T ALL A TION
& OWNER ’ S
MAN U A L
INS T ALL A TION
& OWNER ’ S
MAN U A L
INS T ALL A TION
& OWNER ’ S
MAN U A L
INS T ALL A TION
& OWNER ’ S
MAN U A L
INS T ALL A TION
& OWNER ’ S
MAN U A L
The information in this manual is the property of Patterson-Kelley. The descriptions and specifications contained in this manual were in effect at the time this
manual was approved for publication. While Patterson-Kelley will continue to support earlier model boilers to within a reasonable time limit, we reserve the
right to discontinue models and replacement parts at any time or change specifications or design without notice and without incurring any obligation.

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
Page vi
&
NOTE:
THIS MANUAL IS A SUPPLEMENT TO THE
APPLICABLE BOILER INSTALLATION &
OWNER’S MANUAL
PRIOR TO INSTALLATION,
REFER TO THE
MACH®CM300-C1050 NURO
INSTALLATION AND OPERATION MANUAL (2019)
MnR300 & MnRP300 CM300
MnR399 & MnRP399 CM399
MnR500 & MnRP500 CM500
MnR750 & MnRP750 C750
MnR1050 & MnRP1050 C1050

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Table of Contents
1.... INTRODUCTION.................................................................................................................................VII
2.... SAFETY ................................................................................................................................................1
2.1 GENERAL..................................................................................................................... 1
2.2 TRAINING..................................................................................................................... 2
2.3 SAFETY FEATURES....................................................................................................... 2
2.4 SAFETY LABELS ........................................................................................................... 2
2.5 SAFETY PRECAUTIONS ................................................................................................. 3
2.5.1 Electrical Hazards................................................................................................... 3
2.5.2 Burn, Fire, and Explosion Hazards.......................................................................... 3
2.5.3 Crush Hazards........................................................................................................ 3
2.5.4 Chemical Hazards .................................................................................................. 4
2.5.5 Pressure Hazards................................................................................................... 4
2.5.6 Slip, Fall Hazards.................................................................................................... 4
3.... INSTALLATION....................................................................................................................................4
3.1 RECEIVING AND STORAGE ............................................................................................ 4
3.1.1 Initial Inspection...................................................................................................... 4
3.1.2 Storage Prior to Installation..................................................................................... 4
3.2 COMPLIANCE WITH CODES............................................................................................ 5
3.3 SETUP......................................................................................................................... 5
3.3.1 Foundation and Placement..................................................................................... 5
3.3.2 Clearances (MnR & MnRP sizes 300,399, & 500)................................................... 6
3.3.3 Clearances (MnR & MnRP sizes 750 & 1050) ........................................................ 7
3.3.4 Expansion Tank & Fill System ................................................................................ 8
3.4 CONNECTING TO THE DOMESTIC HOT WATER SYSTEM (MNRINDIRECT DOMESTIC WATER
HEATING MODELS)................................................................................................................... 9
3.4.1 Domestic Hot Water Piping Connections (MnR300-MnR399-MnR500)................... 9
3.4.2 Domestic Hot Water Piping Connections (MnR750-MnR1050)..............................10
3.4.3 Example Domestic Hot Water System Installation (Single Unit).............................11
3.4.4 Example Domestic Hot Water System Installation (Multiple Units).........................12
3.4.5 Domestic Hot Water Piping Considerations ...........................................................13
3.4.6 Flushing the Domestic Water.................................................................................14
3.4.7 Filling the System ..................................................................................................14
3.5 CONNECTING TO THE POOL WATER SYSTEM (MNRP INDIRECT POOL HEATING MODELS)16
3.5.1 Pool Hot Water Piping Connections (MnRP300, 399, & 500).................................16
3.5.2 Pool Hot Water Piping Connections (MnRP750 &1050).........................................17
3.5.3 Example Pool Heating System (Single Unit)..........................................................18
3.5.4 Example Pool Heating System (Multiple Units with Duration).................................19
3.5.5 Pool Water Piping Considerations .........................................................................20
3.5.6 Flushing Pool Water ..............................................................................................20
3.5.7 Filling Pool Water Side of System..........................................................................21
3.6 ELECTRICAL CONNECTION ...........................................................................................21
3.6.1 Control Panel for the Circulating Pumps ................................................................23
3.6.2 High Voltage (TB2) Terminal Block........................................................................24
3.6.3 Low Voltage (TB1) Terminal Block.........................................................................24
3.7 DRAIN VALVE AND PIPING ............................................................................................24
3.8 PRE-START CHECK LIST..............................................................................................25
3.9 SAFETY CHECKS .........................................................................................................25
3.9.1 Test of Circulation Pumps......................................................................................25

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
Page vi
3.9.2 Test of High Temperature Limit Aquastat...............................................................26
3.9.3 Test of Domestic Water Temperature Sensor........................................................26
3.9.4 Test of Operating Aquastat....................................................................................26
4.... NURO CONTROL SYSTEM SETUP..................................................................................................27
4.1 NURO CONTROL SYSTEM OVERVIEW ..........................................................................27
4.2 DOMESTIC HOT WATER SETUP WIZARD........................................................................28
4.2.1 Domestic Hot Water Control (Aquastat in Storage Tank) .......................................29
4.2.2 Domestic Hot Water Control (Temperature Sensor in Storage Tank) –Preferred..30
4.2.2.1 Sensor as an Aquastat...................................................................................31
4.2.2.2 Sensor for Remote Modulation.......................................................................32
4.2.3 On/Off Differentials................................................................................................32
5.... MAINTENANCE..................................................................................................................................33
5.1 MAINTENANCE AND INSPECTION SCHEDULE..................................................................33
5.1.1 Daily ......................................................................................................................33
5.1.2 Weekly...................................................................................................................33
5.1.3 Monthly..................................................................................................................33
5.1.4 Annually.................................................................................................................34
5.2 ACCESSING THE COMPONENTS (MNR&MNRP, 750 &1050)........................................34
5.3 TROUBLESHOOTING.....................................................................................................35
6.... PARTS/TECHNICAL SUPPORT........................................................................................................36
6.1 WIRING DIAGRAM –BOILER POWER &PUMP CONTROL .................................................36
6.2 WIRING DIAGRAM –CONTROLS FOR DHW OPERATION..................................................37
6.3 MNR300, 399, &500 COMPONENTS ............................................................................39
6.4 MNR750 &1050 COMPONENTS –APPLIANCE SIDE.......................................................40
7.... RECOVERY PERFORMANCE DATA................................................................................................41
7.1 P-K MACH ‘N’ROLL™RECOVERY PERFORMANCE DATA AT 40F...................................41
7.2 P-K MACH ‘N’ROLL™RECOVERY PERFORMANCE DATA AT 50F...................................42
7.3 P-K MACH ‘N’ROLL™RECOVERY PERFORMANCE DATA AT 60F...................................43
7.4 P-K MACH ‘N’ROLL™RECOVERY PERFORMANCE DATA AT 70F...................................44
7.5 P-K MACH ‘N’ROLL™RECOVERY PERFORMANCE DATA AT 80F...................................45
7.6 P-K MACH ‘N’ROLL™POOL PERFORMANCE DATA........................................................46
8.... P-K MACH®(MACH & ROLL) SPECIFIC LIMITED WARRANTY.....................................................47

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
Page vii
1 Introduction
This manual describes the installation and operation
of the P-K MACH ‘n’ Roll™condensing indirect
domestic hot water and pool heating systems for use
with P-K MACH®CM300, CM399, CM500, C750 &
C1050 boilers:
CM300-CM399-CM500 and C750-C1050:
•Natural Gas, 120V (single phase), 60
Hertz
•Propane Gas, 120V (single phase), 60
Hertz
It is important to note that the P-K MACH ‘n’ Roll™
system is an add-on package to the standard P-K
MACH®appliance. Please refer to the latest edition
of the P-K MACH®CM300 through C1050 NURO
installation and operation manual for detailed
appliance operation requirements before installing the
P-K MACH 'n' Roll™condensing indirect domestic hot
water or pool heating systems.
Individual differences between each P-K MACH ‘n’
Roll™model will be called out and defined in separate
sections and the titles of these sections will include
the appliance model number. If model numbers are
not listed in the section title, that section is common
to all models.
If you have any questions on the information
contained within, or do not fully and completely
understand the content, please contact Patterson-
Kelley Technical Service at 570.476.7261 or toll free
at 877.728.5351.
The P-K MACH ‘n’ Roll™systems and P-K MACH®
appliance are only a part of a complete heating
system. This add-on package may be fully
operational and yet because of poor circulation,
control, or other operating characteristics not deliver
hot water to the desired location. Additional
equipment such as storage tank(s), storage tank
temperature sensor, pumps, flow switches, balancing
valves, and check valves will be required for
satisfactory operation of any system. Patterson-
Kelley cannot be responsible for the design or
operation of such systems and a qualified engineer or
contractor must be consulted.
If the information in this manual
is not followed, fire or explosion
may result causing property
damage, personal injury or loss
of life.
Do not store or use gasoline or
other flammable vapors or liquids
in the vicinity of this or any other
appliance.
Installation and service must be
performed by a qualified installer,
service agency, or the gas supplier.
WHAT TO DO IF YOU SMELL GAS:
•Do not try to light any
appliance.
•Do not touch any electrical
switch; do not use any phone
in your building.
•Immediately call your gas
supplier from a neighbor’s
phone. Follow the gas
supplier’s instructions.
If you cannot reach your gas
supplier, call the fire department.
It is essential to read,
understand, and follow the
recommendations of this
manual before installing,
operating or servicing this
equipment. Failure to do so
could result in personal injury
or death.
Installation and service must be
performed by a qualified and
knowledgeable individual who
has been certified on the P-K
MACH®
Appliance. The features
which permit this boiler to
achieve high-efficiency
performance can be misused
which could result in personal
injury or death.

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
Page 1
2 Safety
2.1 General
The P-K MACH ‘n’ Roll™MnR & MnRP models with
sizes 300/399/500/750/1050 must be:
•Installed, operated and serviced in accordance
with instructions contained in this manual and
other supplemental manuals.
•Installed by qualified personnel in accordance
with designs prepared by qualified facility
engineers including: structural, mechanical,
electrical and all other applicable disciplines.
•Operated and serviced in accordance with a
comprehensive safety program determined
and established by the customer. Do not
attempt to operate or service until such a
program has been established.
•Operated and serviced by experienced,
qualified and properly trained personnel in
accordance with all applicable codes, laws
and regulations.
Upon receiving the P-K MACH®appliance and P-K
MACH ‘n’ Roll™system, inspect for signs of shipping
damage. Some damage may be hidden. Unpack the
appliance, open the front and side doors and inspect
the equipment. Verify that the total number of pieces
shown on the packing slip agrees with those actually
received.
NOTICE! Each safety device must be maintained
and checked per the recommended schedule.
Refer to Section 3.7 of this manual.
The P-K MACH ‘n’ Roll™
water heater is a dynamic system that is designed
to heat water in a storage tank or pool to a wide
range of temperatures. The P-K MACH ‘n’ Roll™
system is capable of heating water to scalding
temperatures. Refer to your local codes for
guidelines on compliance for domestic hot water or
pool water systems. A thermostatic mixing valve
may be required to prevent scalding.
Installation and service must be
performed by a qualified
installer, service agency, or gas
supplier. Failure to install the
equipment in accordance with
this manual could result in an
unsafe operating condition.
NOTICE!
Controls and other equipment that
are damaged or fail due to weather
exposure are not covered by
warranty.
The appliance is heavy and
requires additional technicians
to support and move the unit(s)
during installation. Use
extreme caution to avoid
dropping the appliance or cause
any bodily injury while lifting or
handling. When positioning
this appliance, maintain positive
control of it at all times. Do not
attempt to move the appliance
on surfaces that are not level.
Failure to heed this warning
could result in personal injury
or death.
Bumping hazard from overhead
ducts! Install all components
with adequate vertical
clearances. Insufficient
clearance can restrict the
service access, increasing the
possibility of injury.
NOTICE!
The P-K MACH ‘n’ Roll™ may be
installed on a combustible floor;
however, the appliance must never
be installed on carpeting.

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
Page 2
2.2 Training
Proper training is the best protection against accidents. Factory training sessions are available to
qualified individuals who are sponsored by the local Patterson-Kelley representative.
It is essential to read, understand, and follow the
recommendations of this manual before installing,
operating, or servicing this equipment. Failure to do
so could result in fire or explosion and serious injury,
death, and/or property damage.
Operating and service personnel must be thoroughly
familiar with the basic construction of the P-K MACH®CM300/CM399/CM500 or C750/C1050
appliances, the use and locations of the controls, the operation of the appliances, adjustment of their
various mechanisms, and all applicable safety precautions. If any of the provisions of this manual are
not fully and completely understood, contact Patterson-Kelley Technical Service at 570.476.7261 or toll
free at 877.728.5351.
2.3 Safety Features
It is the responsibility of the customer to maintain the safety features, including but not limited to: guards,
safety labels, safety controls, interlocks, lockout devices and temperature/pressure safety relief valves.
2.4 Safety Labels
The following words are used in this manual to denote the degree of seriousness of the individual
hazards.
Indicates an imminently hazardous situation which, if not avoided, will result
in death or serious injury. This signal word is to be limited to the most extreme situations.
Indicates a potentially hazardous situation which, if not avoided, could result
in death or serious injury.
Indicates a potentially hazardous situation which, if not avoided, may result
in minor or moderate injury. It may also be used to alert against unsafe practices.
NOTICE/NOTE - NOTICE is the preferred signal word to address practices not related to personal
injury. The safety alert symbol is not used with this signal word.

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
Page 3
2.5 Safety Precautions
Provide a suitable location for the P-K MACH ‘n’ Roll™system, away from normal personnel traffic, with
adequate working space, adequate clearances, proper ventilation and lighting, with a structure
sufficiently strong and rigid to support the weight of the boiler, P-K MACH ‘n’ Roll™system, all piping, and
accessories.
2.5.1 Electrical Hazards
•Shock hazard! Properly lockout/tag out the electrical service and all
other energy sources before working on or near the boiler.
•Shock hazard! Do not spray water directly on this boiler or on any
electrical components.
•Electrical hazard! Do not alter wiring connections.
2.5.2 Burn, Fire, and Explosion Hazards
•Burn, fire, and explosion hazards! Installation must be in strict conformance
to all applicable codes and standards including NFPA 54, ANSI Z223.1 and
CAN/CSA B.149.
•Burn hazard! Possible hot surfaces. Pipes and internal components could
be hot. Do not touch piping or internal components during operation or
immediately after shutdown of the appliance.
•Burn hazard! Hot fluids. Use caution when servicing or draining appliance.
2.5.3 Crush Hazards
•Lifting hazards! Use properly rated lifting equipment to lift and position the
boiler. The load is unbalanced. Test balance before lifting 3 ft. above the
floor. Do not allow personnel beneath the lifted load. Refer to approximate
weights in the table.
Model
Shipping Weight in Pounds
MnR300/MnRP300
1390 lbs
MnR399/MnRP399
1417 lbs
MnR500/MnRP500
1417 lbs
MnR750/MnRP750
1340 lbs
MnR1050/MnRP1050
1440 lbs
Hot Surface
General Warning
General Warning
The P-K MACH ‘n’ Roll™water heater is a dynamic system that is designed to
heat water in a storage tank or pool to a wide range of temperatures. The P-K MACH ‘n’ Roll™
system is capable of heating water to scalding temperatures. Refer to your local codes for guidelines
on compliance for domestic hot water or pool water systems. A thermostatic mixing valve may be
required to prevent scalding.

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
Page 4
2.5.4 Chemical Hazards
•Chemical hazards from cleaning products. Use caution when cleaning the
system. The use of professional assistance is recommended. Use safe
procedures for the disposal of all cleaning solutions.
2.5.5 Pressure Hazards
•Pressure hazard! Hot fluids. Install isolation valves on appliance water inlet
and outlet. Make sure isolation valves are closed before servicing.
•Pressure hazard! Hot fluids. Annually test safety relief valve for proper
operation. Do not operate with faulty relief valve(s).
2.5.6 Slip, Fall Hazards
•Tripping hazard! Do not install piping on floor surfaces. Maintain clear path
around the P-K MACH ‘n’ Roll™system.
•Slip and fall hazard! Use drip pan to catch water while draining. Maintain dry
floor surfaces.
•Fall hazard! Do not stand on the P-K MACH ‘n’ Roll™system or the P-K
MACH®appliance.
3 Installation
3.1 Receiving and Storage
3.1.1 Initial Inspection
Upon receiving the P-K MACH ‘n’ Roll™system, inspect it for signs of shipping damage. Since
some damage may be hidden, unpack the product, open the front, and side doors to inspect. Verify that
the total number of pieces shown on the packing slip agrees with those actually received.
3.1.2 Storage Prior to Installation
If the P-K MACH ‘n’ Roll™system is not installed immediately, it must be stored in a location adequately
protected from the weather, preferably indoors. If this is not possible, then it should remain in the
shipping container and be covered by a tarpaulin or other waterproof covering.
General Warning
General Warning
General Warning
Installation and service must be performed by a qualified installer, service
agency, or gas supplier.
NOTICE! Note any damage, suspected potential damage, or shortage of materials on the freight bill
and immediately notify the carrier. File all claims for shortage or damage with the carrier. Claims for
hidden damages must be filed with your carrier within 7 days.
NOTICE! Controls and other equipment that are damaged or fail due to weather exposure are not
covered by warranty.

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
Page 5
3.2 Compliance with Codes
The brazed plate heat exchanger is constructed and stamped in accordance with ASME Boiler and
Pressure Vessel Code, Section VIII, Division 1 for 219 psig maximum operating pressure. However,
certain components in the domestic piping have a maximum pressure rating of 150 psig. Therefore, the
domestic side pressure must never exceed 150 psig.
Patterson-Kelley recommends a pressure-only relief valve constructed and stamped in accordance with
ASME Boiler and Pressure Vessel Code, Section VIII with a maximum 150 psig set pressure. Most
MACH ‘n’ Roll installations will be piped to a storage tank which will feature a T&P relief valve (excluding
pool heater versions). Ensure that any pressure relieving devices installed in the domestic hot water
system prevent the pressure from exceeding 150 psig.
Please refer to the P-K MACH®CM300 through C1050 NURO installation and operation manuals for
code compliance related to the P-K MACH®appliance.
3.3 Setup
3.3.1 Foundation and Placement
Provide a firm, level foundation, preferably of concrete. The P-K MACH ‘n’ Roll™system and P-K
MACH®appliance must be level to function properly. To assist in leveling the equipment, the four (4)
adjustable leveling feet (1/2” – 13 NC) must be installed and adjusted accordingly. The adjustable feet
also provide adequate floor clearance and prevent distortion/twisting of the cabinet enclosure.
ADJUSTABLE LEVELING FEET

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
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3.3.2 Clearances (MnR & MnRP sizes 300,399, & 500)
Since the P-K MACH ‘n’ Roll™is designed to sit underneath the applicable P-K MACH®appliance, it
generally requires the same clearances as the appliance itself. Some additional clearance
considerations may be required for the domestic hot water piping. The P-K MACH ‘n’ Roll™system is
designed to be serviced from the front, so ensure there are no obstructions present in front of the unit.
If the MACH ‘n’ Roll™is to be installed near combustible surfaces, there must be six (6”) inches minimum
clearance. Failure to provide adequate service clearances, even with non-combustible surfaces, may
present problems during routine maintenance of the appliance. The appliance must be installed in a
space large in comparison to the appliance as described in the National Fuel Gas Code, NFPA 54/ANSI
Z223.1, Latest Edition.
Type of Surface
Dimensions (inches)
A
B
C†
D
E**
CSA Minimum Clearances to
Combustibles
6
6
6
6
6
Clearance to Non-Combustible Surfaces
0
0
0
0
0
Recommended Service Clearances
36
0
24
24
24**
† “C" dimension includes clearance to remove the burner. Do not put pipes, ducts, etc. in area above the
appliance.
*CSA minimum. Actual clearance depends upon venting requirements.
NOTICE! The P-K MACH ‘n’ Roll™system may be installed on a combustible floor; however, it must
never be installed on carpeting.

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
Page 7
** Right-Side service access (“E” Dimension”) is needed to view the boiler’s runout/safety labels, as well as
viewing the combustion flame.
3.3.3 Clearances (MnR & MnRP sizes 750 & 1050)
Since the P-K MACH ‘n’ Roll™is designed to sit underneath the applicable P-K MACH®appliance, it
generally requires the same clearances as the appliance itself. Some additional clearance
considerations may be required for the domestic hot water piping. The P-K MACH ‘n’ Roll™system is
designed to be serviced from the front, so ensure there are no obstructions present in front of the unit.
If the appliance is to be installed near combustible surfaces, there must be twenty-four (24”) inches
minimum clearance. Failure to provide adequate service clearances, even with non-combustible
surfaces, may present problems during routine maintenance of the appliance. The appliance must be
installed in a space large in comparison to the appliance as described in the National Fuel Gas Code,
NFPA 54/ANSI Z223.1, Latest Edition.
Type of Surface
Dimensions (inches)
A
B
C
D**
E
CSA Minimum Clearances to
Combustibles
24
24*
24
24
24
Recommended Service Clearances
30
24*
24
36**
24
* CSA minimum. Actual clearance depends upon venting requirements.
** Left-Side Service access (“D” Dimension) is helpful for routine maintenance access. Patterson-Kelley
recommends equal clearance between each appliance when there is insufficient access at the rear to
allow for service and adjustment

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
Page 8
3.3.4 Expansion Tank & Fill System
Before making any mechanical connections to the P-K MACH ‘n’ Roll™system or to the P-K MACH®
appliance, it is imperative that the expansion tank / fill system be checked for a suitable fill pressure. The
expansion tank ships with a 12 psig precharge, but it is possible that air pressure may reduce during
shipment. Locate the Schrader valve on the expansion tank as shown by the white arrow in the images
below (the front sheet metal panels are removed for clarity).
Use a pressure gauge to verify the air pressure is at least 12 psig. If the pressure is insufficient, use an
air pump with built-in pressure gauge to charge the air pressure to a minimum of 12 psig before making
ANY mechanical connections. The maximum air pressure need not exceed 20 psig.
The expansion tank assembly features an integral fill valve which floods the appliance loop with water to
the same air pressure that exists on the bladder. As the appliance operates, you may notice that the
appliance loop pressure exceeds the initial fill pressure which is completely normal and is due to thermal
expansion of the appliance water.

P-K MACH®Gas Fired Appliance
Technical Service 1.877.728.5351
Revised: January 3, 2020
Released: January 3, 2020
Patterson Kelley 2020
All Rights Reserved.
1004905989 MnR & MnRP 300-399-500-750-
1050 NURO Rev C (Jan-2020).docx
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3.4 Connecting to the Domestic Hot Water System (MnR Indirect Domestic
Water Heating Models)
The P-K MACH ‘n’ Roll™is designed to occupy the space underneath the applicable P-K MACH®
appliance. The steel piping is connected to & from the P-K MACH®appliance at the factory, but the 2”
copper piping must be connected to the domestic hot water system.
3.4.1 Domestic Hot Water Piping Connections (MnR300-MnR399-MnR500)
On the MnR300-MnR399-MnR500, the domestic hot water piping connections (2” type L copper) are
located on the left hand side of the unit as shown below:
DHW SUPPLY (OUT)
DHW RETURN (IN)
NOTICE! There are a variety of ways to connect to the domestic water piping on the MACH ‘n’ Roll™,
but any sweat/soldered connections must use lead-free solder. Also, any brass or bronze pipe
fittings, isolation valves, unions, check valves, etc. must also be lead-free.

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3.4.2 Domestic Hot Water Piping Connections (MnR750-MnR1050)
On the MnR750 & MnR1050, the domestic hot water piping connections (2” type L copper) are located at
the left rear side of the unit as shown below:
DHW SUPPLY (OUT)
DHW RETURN (IN)
NOTICE! There are a variety of ways to connect to the domestic water piping on the MACH ‘n’ Roll™,
but any sweat/soldered connections must use lead-free solder. Also, any brass or bronze pipe
fittings, isolation valves, unions, check valves, etc. must also be lead-free.

P-K MACH®Gas Fired Appliance
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Released: January 3, 2020
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3.4.3 Example Domestic Hot Water System Installation (Single Unit)
It is important to note that the MACH ‘n’ Roll™is designed to operate in conjunction with a domestic
water storage tank. From the initial call for heat, it takes approximately two minutes until the P-K MACH®
appliance operates at maximum power, so the storage tank needs to be sized appropriately for the
application. The image below shows a sample piping arrangement for a typical domestic hot water
system.
The P-K MACH n’ Roll™system features a thermowell in the domestic hot water supply connection which
can be used for a normally closed high temperature limit aquastat. Alternatively, this high temperature
limit aquastat can be installed in the domestic water storage tank. The normally closed and common
terminals on the aquastat should be wired to the appliance’s START INTERLOCK #1 terminals (TB2-7 &
TB2-8). If the domestic water temperature exceeds the high temperature limit aquastat, the MACH ‘n’
Roll™will go into a blocking error to prevent a high temperature condition. The system will remain in
blocking for 5 minutes after which the NURO control will lockout.
The P-K MACH ‘n’ Roll™system requires either a normally-closed operating temperature aquastat or a
12kΩthermistor-type temperature sensor installed in the lower 1/3rd of the domestic water storage tank,
wired to the appliance’s DHW STAT/SENSOR terminals (TB1-7 & TB1-8). Ensure the insertion depth is

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sufficient to achieve an accurate tank temperature reading. If using a thermowell, thermal paste is
recommended.
3.4.4 Example Domestic Hot Water System Installation (Multiple Units)
The image below shows a sample piping arrangement for a typical domestic hot water system with two
P-K MACH ‘n’ Roll™units.
NOTE: Ensure a check valve is installed on the DHW supply piping of each MACH ‘n’ Roll™in the
system. This will ensure the hot water is directed to the storage tank, and isn’t allowed to backflow
through offline MACH ‘n’ Roll™units.

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3.4.5 Domestic Hot Water Piping Considerations
It is recommended to install the P-K MACH ‘n’ Roll™system as close as possible to the domestic water
storage tank in order to minimize the overall length of piping. The P-K MACH ‘n’ Roll™system features a
fractional horsepower domestic water circulation pump which may have difficulty providing the design
flow rate if the piping is too long, or if there is excessive pressure drop through elbows, tees, valves, etc.
The pump performance curves and flow requirements are listed below for reference:
MnR300, MnR399 & MnR500 (1/3HP 3-Speed Lead-Free Bronze Circulation Pump)
MnR750 & MnR1050 (2/5HP Fixed Speed Lead-Free Bronze Circulation Pump)
Design Flow Conditions
Model
GPM
ΔP
through
MnR
(FT Head)
ΔP
Available
(FT Head)
MnR300
25
5
9
MnR399
MnR500
Design Flow Conditions
Model
GPM
ΔP
through
MnR
(FT Head)
ΔP
Available
(FT Head)
MnR750
60
5
9
MnR1050

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3.4.6 Flushing the Domestic Water
The P-K MACH ‘n’ Roll™system features an expansion tank/fill valve assembly that provides water to the
P-K MACH®appliance and its piping. A dual-check valve ensures that the water in the appliance loop
cannot re-enter the domestic loop. It is imperative that the water quality guidelines required for a P-K
MACH®appliance be strictly followed. The P-K MACH®appliance heat exchanger is made of an
aluminum alloy. All heat exchangers require proper water conditions to remain efficient and function
properly. For information log on to our website: www.pattersonkelley.com for Multi-Metal Systems Water
Quality Standards information as this applies to the warranty of the appliance’s heat engine.
Before the initial fill, ensure that any and all sediment or particulates have been removed from the
domestic water. Ensure that any isolation valves between the domestic water storage tank and the P-K
MACH ‘n’ Roll™system are closed. If available, use a drain valve on the domestic water storage tank to
purge sediment and particulates.
3.4.7 Filling the System
Before filling the system, ensure all the mechanical connections are complete. Also, refer to the P-K
MACH®CM300 through C1050 NURO installation and operation manual to ensure the appliance’s
pressure relief valve is installed correctly.
•STEP 1 –Remove either the front or left panel from the P-K MACH ‘n’ Roll™system to provide
better access to the expansion tank/fill valve assembly isolation valve.
•STEP 2 –If available, close the manual isolation valves in the domestic piping between the
domestic water storage tank and the P-K MACH ‘n’ Roll™system.
•STEP 3 –Close the manual isolation valve ahead of the expansion tank/fill valve assembly.
Refer to Section 3.3.4 to ensure the expansion tank is charged to at least 12 psig and not more
than 20 psig.
•STEP 4 –Close the drain valves on the appliance and domestic piping.
•STEP 5 –Open the cap on the automatic air vent in the appliance piping.
NOTICE! Glycol or other treatment chemicals added to the system must be certified by the chemical
manufacturer for use in multi-metal systems that include cast aluminum appliances.
NOTICE! Under no circumstances should petroleum based cleaning or sealing compounds be used
in the appliance system.
NOTICE! Under no circumstances should the hydronic system be flushed while the appliance is
attached to the system since the debris or corrosion products could accumulate in the appliance and
plug the appliance heat exchanger.
NOTICE! Performance data for recovery capacity of the P-K MACH ‘n’ Roll™system (see Section 7)
was performed with pure water with no additives. Chemical additives will impact the performance of
the P-K MACH ‘n’ Roll™system.
NOTICE! If the piping system attached to this unit will be chemically cleaned, the appliance must be
disconnected from the system and a bypass installed so that the chemical cleaning solution does not
circulate through the appliance. Following chemical cleaning, the system should be thoroughly rinsed
to remove cleaning agents prior to reconnecting the appliance to the system.

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•STEP 6 –Open the stem of the appliance’s safety relief valve.
•STEP 7 –If available, open the manual isolation valves in the domestic piping. This will fill the
domestic side of the heat exchanger with water.
•STEP 8 –Open the manual isolation valve ahead of the expansion tank/fill valve assembly. This
will fill the appliance side of the heat exchanger with water.
•STEP 9 –When water escapes from the boiler’s safety valve discharge, close the stem of the
safety relief valve.
•STEP 10 –Ensure the water pressure is at least 12 psig in the appliance piping. If the water
pressure is less than 12 psig, drain the water in the appliance piping and refer to Section 3.3.4 to
charge the expansion tank. When the expansion tank is charged properly, repeat Steps 1
through 9.
•STEP 11 –Check for any leaks in the appliance piping, especially at the Victaulic couplings as
these may have loosened during shipment. Tighten or reseat the connections if necessary.
•STEP 12 –Check for any leaks in the domestic piping, especially at the Victaulic couplings and
pump flanges which may have loosened during shipment. Tighten or reseat the connections if
necessary.