Intellihot Combi i200X, Combi i250X, Combi i251X, Combi i201X Technical Manual

The rst gas-red tankless
water heaters designed
and built in the USA.

Designed and
built in the USA

TECHNICAL GUIDE

COMBI

Hot Water + Space Heating

+

intelligent hot water.

Maximum domestic hot water with
space heating.

Provide endless hot water while maintaining a comfortable space
temperature. In most combi boilers, hot water heating is an after­thought. Intellihot’s combi models deliver a large quanitity of hot
water while simultaneously keeping your house comfortable. They
elegantly combine domestic hot water and space heating with one
unit, one gas line and one vent.

Intellihot’s combi models deliver a full quantity (200MBH or
250MBH) of domestic hot water when needed and easily modulate
down to efciently deliver up to 130 MBH of space heating.

How does it work?

Turn on a faucet and Intellihot will begin to deliver hot water. If
space heating is called for, the on-board circulator begins to
deliver up to 135,000 btu/h to the internal plate-type heat
exchanger (PTHE) simultaneously. With no diverting valve to adjust,
fail or malfunction, the Intellihot combi is extremely robust. The
PTHE separates the domestic hot water from the space heating
water to maintain safety and quality.

Designed and built in the USA.

Founded in 2005, after a traditional water heater broke down
and ooded our founder’s basement, Intellihot today designs,
manufactures and builds tankless water heaters for commercial,
industrial and residential applications—the rst to do so entirely
in the United States.

PLATE-TYPE HEAT
EXCHANGER (PTHE)

PERFORMANCE

• Dedicated ASME-rated, stainless brazed plate
heat exchanger for space heating capable of
up to 135,000 btu/h

• Separates domestic hot water from the space
heating side to maintain safety and integrity of
the domestic side

• Units allow for maximum domestic hot water

supply while SIMULTANEOUSLY delivering up to
130,000 btu/h of space heating with no three-way
valve to fail

• Combines the commercially proven 316L ex heat

exchanger and integral pump with a plate-type heat
exchanger for seamless space heating

• Plastic vent temperature overshoot control

maintains safe stack temperature below the
vent’s maximum temperature rating

• Simple install with self-learning and outdoor auto-

reset for the most comfort and maximum savings

• Eliminates need for a primary/secondary loop

setup and large space requirements of a boiler/
storage tank installation

• No low loss header system needed

HEATED
BUFFER TANK

• Integrated half-gallon buffer tank
eliminates temperature spikes and
cold-water sandwiches

• +/-2°F temperature stability

BURNER SYSTEM

• Features a radially red, downward-blowing,
premixed burner with a negative pressure gas
valve and plenum design

• Delivers a more stable ame under a wide
range of operating conditions, including low
gas pressure, wind and non-equal pressure
zone terminations

• Easily converts from natural gas to LP with the
turn of a screw—no additional parts required
and one SKU for easier inventory management

SELF-LEARNING
RECIRCULATION

Use Intellihot under-sink valve
(part # IGT-SPR-0061)

• Get instant hot water (eliminates
water waste) for any application

• Zero ow-rate activation

INTELLIHOT COMBI | 01 WHAT’S INSIDE

316L FLEX HEAT
EXCHANGER

• Floats freely and acts like a spring to
accommodate all thermal shocks and stresses

• Made of 316L stainless steel for superior
corrosion and erosion resistance

• Self-descaling heat exchanger design prevents
scale buildup

• No welds on the water side ensure robustness
to chlorides

• Low pressure drop compared to other tankless
designs

• Energy reduction up to 40%+ compared to
tank-type water heaters and 15%+ over non­condensing water heaters

WHAT’S INSIDE?

Contact Information

Intellihot Green Technologies Inc.
2900 W. Main Street, Galesburg, IL 61401
phone: [phone]
email: [e-mail]
web: www.intellihot.com

SIMULTANEOUS HOME
HEATING AND HOT WATER
PRODUCTION.

UP TO 4 SHOWERS NONSTOP UP TO 135,000 BTU/HR

+

INTELLIGENT CONTROLS

• Units can be set to control temperature or
allow maximum ow delivery—ideal for short
duration demand spikes or large commercial
dump loads tied with storage tanks

• After every ring cycle, system circulates
internally to equalize temperature, eliminate
hotspots and prevent scale (pump models only)

WATER INLET STRAINER

• Strainer included and factory installed on
the units to deliver debris-free inlet water to
the system

EASY-ACCESS
CONNECTIONS

• Thermostat/pump/outdoor reset

03 PLATE PERFORMANCE/PRESSURE DROP02 DIMENSIONS

INTELLIHOT COMBI

FRONT VIEW

TOP VIEW

WEIGHT: 98 LBS.

SIDE VIEW

BOTTOM VIEW

COMBI DIMENSIONS SPACE HEATING PERFORMANCE

SPACE HEATING SIDE - PRESSURE DROP

4 GPM

Supply Temp (°F)

120 130 140 150 160 170 180

Return Temp (°F)

90 100 100 110 110 120 120 130 130 140 150 160

Btu/h

58,000 39,000 57,500 38,500 57,000 37,800 57,700 38,200 57,100 38,600 37,700 34,500

6 GPM

Supply Temp (°F)

120 130 140 150 160

Return Temp (°F)

90 100 100 110 110 120 120 130 140

Btu/h

85,200 56,900 85,000 56,400 86,000 57,000 86,000 56,262 56,804

8 GPM

Supply Temp (°F)

120 130 140 150

Return Temp (°F)

90 100 100 110 110 120 130

Btu/h

114,500 77,030 114,500 76,500 102,900 75,900 75,100

10 GPM

Supply Temp (°F)

120

Return Temp (°F)

92

Btu/h

136,500

SPACE HEATING:
SUPPLY - 1” NPT

SPACE HEATING:
RETURN - 1” NPT

SPACE HEATING:
SUPPLY - 1” NPT

SPACE HEATING:
RETURN - 1” NPT

0 2 4 6

2 .86

0 0

4 1.7

6 2.6

8 3.5

10 4.3

8 10 12

FLOW RATE (GPM)

(FT OF HEAD)

(PSI)

PRESSURE DROP

Single Zone, Single or Multiple Loop Baseboard Single Pump, Multiple Zones, Multiple Loop Baseboard, Using Individual Thermostats

Single Pump, Multiple Zones, Multiple Loop Baseboard,

Using External Valve Controller

Multiple Zones with Multiple Heating Systems, Multiple Temperatures,

Using External Zone Pump Controller and Individual Thermostats

05 PIPING CIRCUITS04 PIPING CIRCUITS

INTELLIHOT COMBI

PIPING CIRCUITS

Cold Water

Isolation

Kit

Ball

Valve

Gate
Valve

Strainer
(Filter)

Preventer

Union Air

Separator

Expansion

Tank

Thermostat Manifold

Set

PumpPressure
Relief
Valve

Drain
Valve

Pressure
Reducing

Valve

KEY

Supply

Heating
System

Pump

Thermostat

Outdoor
Reset

Return

72°

72°

Single Zone, Multiple Loop Radiant

* LWCO

Cold Water

Isolation

Kit

Ball

Valve

Gate
Valve

Strainer
(Filter)

Preventer

Union Air

Separator

Expansion

Tank

Thermostat Zone

Valve

PumpPressure
Relief
Valve

Drain
Valve

Pressure
Reducing

Valve

KEY

Supply

Return

72°

Zone 1 Zone 2 Zone 3 Zone 4 Zone 5 Zone 6

Zone 1 PumpZone 2 Pump Zone 3 PumpZone 4 Pump Zone 5 Pump Zone 6 Pump

Boiler TT

Zone Controller

Heating
System

Pump

Thermostat

Outdoor
Reset

72° 72° 72°

Single Pump, Multiple Zones, Multiple Loop Baseboard,

Using External Zone Valve Controller

Cold Water

Isolation

Kit

Ball

Valve

Gate
Valve

Strainer

(Filter)

Preventer

Union Air

Separator

Expansion

Tank

ThermostatPumpPressure
Relief
Valve

Drain
Valve

Pressure
Reducing

Valve

KEY

Supply

Heating
System

Pump

Thermostat

Outdoor
Reset

Return

72°

72°

Single Zone, Single or Multiple Loop Baseboard

Cold Water

Isolation

Kit

Ball

Valve

Gate
Valve

Strainer
(Filter)

Preventer

Union Air

Separator

Expansion

Tank

Thermostat Zone

Valve

PumpPressure
Relief
Valve

Drain
Valve

Pressure
Reducing

Valve

KEY

Supply

Return

72°

MotorMotorMotor

Heating System

Pump

Thermostat

Outdoor Reset

72° 72° 72°

Single Pump, Multiple Zones, Multiple Loop Baseboard,

Cold Water

Isolation

Kit

Ball

Valve

Gate
Valve

Strainer
(Filter)

Check
Valve

Preventer

Union Air

Separator

Expansion

Tank

ThermostatPumpPressure
Relief
Valve

Drain
Valve

Pressure

Reducing

Valve

KEY

Supply

Return

72°

Zone 1 Zone 2 Zone 3 Zone 4 Zone 5 Zone 6

Zone 1 PumpZone 2 Pump Zone 3 PumpZone 4 Pump Zone 5 Pump Zone 6 Pump

Boiler TT

Zone Controller

Heating
System

Pump

Thermostat

Outdoor
Reset

72° 72° 72°

Primary / Secondary Circuit with Multiple Pumps, Multiple Zone Baseboard,

Using External Zone Pump Controller and Individual Thermostats

* LWCO

Cold Water

Isolation

Kit

Ball
Valve

Gate
Valve

Strainer
(Filter)

Check
Valve

Preventer

Union Air

Separator

Expansion

Tank

ThermostatPumpPressure
Relief
Valve

Drain
Valve

Pressure
Reducing

Valve

KEY

Supply

Return

72°

Manifold Set

Fan CoilThree

Way Valve

Zone 1 Zone 2 Zone 3 Zone 4 Zone 5 Zone 6

Zone 1 PumpZone 2 Pump Zone 3 PumpZone 4 Pump Zone 5 PumpZone 6 Pump

Boiler TT

Zone Controller

Heating

System

Pump

Thermostat

Outdoor
Reset

72° 72° 72°

Multiple Zones, with Multiple Heating Systems, Multiple Temperatures,

Combi Specications

PARAMETERS

MODEL

i200X/i201X* i250X/i251X*

Type

Fuel Preset for NG / LP Convertible

Minimum / Maximum Input (Btu/h) 30,000 / 199,950 30,000 / 250,000

Thermal Efciency 94% 92%

Energy Factor 0.93 N/A

Appliance Annual Fuel Utilization Efciency (AFUE) 91.19% N/A

Combined Appliance Annual Fuel Utilization Efciency
(CAFUE)

Dimensions H X W X D (inches) 26 X 17.4 X 14.9 (3.9 cu. ft)

Weight 98 lbs

Water and Gas Connections 3/4” NPT

Space Heating Connections 1” NPT

Minimum Flow Rate No minimum ow rate in learned or programed modes

Venting Materials Sch. 40 PVC, Sch. 40 CPVC, Polypropylene, Stainless Steel

Max 3” Vent Length - Single Pipe / Power Vent 200 ft, deduct 5 ft per 90° elbow 130 ft, deduct 5 ft per 90° elbow

Max 3” Vent Length - Two Pipe / Direct Vent 100 ft, deduct 5 ft per 90° elbow 65 ft, deduct 5 ft per 90° elbow

Max 2” Vent Length - Single Pipe / Power Vent

26 ft, deduct 5 ft per 90° elbow N/A

(2” not allowed at elevations above 4,000 ft)

Max 2” Vent Length - Two Pipe / Direct Vent

21 ft, deduct 5 ft per 90° elbow N/A

(2” not allowed at elevations above 4,000 ft)

Safety Flame Rod, Thermal Fuse, Overheat Prevention Device, Fan Speed Monitor, Flue Temperature

Monitor, Blocked Vent Detector, Water Shut-Off Valve, 2X10A Fuse, Dual Flame Sensing

Water Pressure Min / Max (PSI) 30 / 150

NG/LP - Minimum Static Gas Pressure 1/2” Black Iron
(non-corrugated)

NG/LP - Minimum Static Gas Pressure 3/4” Black Iron
(non-corrugated)

NG/LP - Maximum Static Gas Pressure 14”

Gas Pressure for Adjustments 8” for NG, 11” for LP

Electrical 120V AC, 60 Hz

Power Consumption 500W (Max 4.2 Amps), 8W (Standby)

FEATURES & PERFORMANCE

i200X/i201X* i250X/i251X*

Space Heating Heat Exchanger Stainless Brazed Plate, Maximum Flow 15 GPM

Domestic Water Heat Exchanger Stainless 316L

Hot Water Capacity (35F Rise) 10.8 13.2

Hot Water Capacity (45F Rise) 8.4 10.3

Hot Water Capacity (77F Rise) 5.0 6.0

Domestic Hot Water Temperature Settings 100 – 140°F

Space Heating Temperature Settings 100 – 180°F

Indoor, Wall-Hung, Fully Condensing, Direct Ignition

91.4% N/A

5” 6”

2.5”

Note: Due to Intellihot’s policy of continuous product improvements, design and technical specications are subject to change without notice. v 10.29.14

WARRANTY (with recirculation)

*ASME “H” certied

Intellihot Green Technologies Inc.
2900 W. Main Street, Galesburg, IL 61401
phone: [phone]
email: [e-mail] · www.intellihot.com

Residential: Heat Exchanger Coil – 12 years, Parts – 3 years, Labor – 1 year

Commercial: Heat Exchanger Coil – 6 years, Parts – 1 year, Labor – 1 year

(i201X & i251X)

(i200X & i201X)