TriangleTube SMART Series, Installation & Maintenance Manual

5

CHAPTER

 2

CHAPTER 2 - INSTALLATION - PIPING

•  If copper pipe is used for domestic water connections, 

first solder pipe to a threaded adapter and then screw 

adapter into cold water inlet on top of water heater. 

Inlet connection contains an internal plastic dip tube 

which can be damaged by heat from soldering.

Do not apply heat to the cold water inlet when 

making sweat connections to water heater. 

Sweat tubing to adapter before fitting adapter 

to cold water inlet of heater. It is imperative that 

no heat be applied to the cold water inlet, as it 

contains a non metallic dip tube.

•  When the water supply pressure is higher than 70 

psig, it is recommended to install a pressure reduc-

ing valve on cold water supply line to prevent wa-

ter loss through T&P relief valve.

•  If the water heater will replace a tankless coil in the 

boiler, disconnect the piping to coil and allow the 

water to drain from coil. Do not plug the tankless coil.

Plugging tankless coil inlet and outlet will re-

sult in substantial property damage, serious 

injury, or death.

2.9.  Thermostatic Mixing Valve

•  It is recommended to install an optional mixing 

valve on the domestic hot water outlet.

•  Mixing valve must comply with ASSE 1017 

NOTICE

DANGER

Table 1 - Piping dimensions

Water  

Heater 

Model

Connections (inches)

Recirculation Dip 

Tube

Draining Dip Tube

Recommend-

ed Minimum 
Boiler Piping

Domestic 

Water  

Inlet/Outlet 

(NPT)

Boiler Water 

Supply/ 

Return 
(NPSC)

Auxiliary Connection 

(NPSC)

Length  

(Inches)

Diam-

eter 

(Inches)

Length 

(Inches)

Diameter 

(Inches)

Diameter 

(Inches)

SMART 30

3/4

1

3/4

34

3/4

34

3/4

1

SMART 40

3/4

1

3/4

43

3/4

43

3/4

1

SMART 50

3/4

1 1/4

3/4

25

3/4

52

3/4

1

SMART 60

3/4

1 1/4

3/4

34

3/4

62

3/4

1 1/4

SMART 80

1 1/2

1 1/2

1 1/2

25

1 1/2

48

1 1/2

1 1/4

SMART 100

1 1/2

1 1/2

1 1/2

32

1 1/2

61

1 1/2

1 1/2

SMART 120

1 1/2

2

1 1/2

32

1 1/2

61

1 1/2

1 1/2

2.11.  Multiple Water Heater Systems

•  Parallel Pipe Recirculation Systems - Manifold recircu-

lation return to all water heaters.

•  Series Piped Systems - Piped return to the leading 

(cold water inlet) water heater. 

•  Install an automatic mixing valve either at the hot wa-

ter outlet of water heater or each hot water faucet.

Failure to install automatic mixing valve 

where recommended will result in serious in-

jury, or death.

DANGER

2.10.  Recirculation Piping.

•  T&P relief valve must be installed in run (straight 

through leg) of tee located at domestic hot water 

outlet of water heater.

•  It is recommended that the recirculation dip tube 

be installed in auxiliary connection using a close 
nipple assembly as shown in 

 Fig. 3 on page 7.

See 

Table 1

 below for diameter and length of dip 

tube.

•  A stainless steel or bronze circulator is required on 

potable water systems.

•  Install automatic mixing valve either at the hot wa-

ter outlet of water heater or each hot water faucet