36
LP-520 REV. 7.26.16
B. DHW PIPING
Use both thread tape and pipe dope to connect to th
e ¾” domestic water inlet and outlet. A shut off valve between the city water supply
and DHW inlet is recommended for ease of service.
HTP offers threaded ¾” DHW tankless isolation valves with DHW pressure relief
valve for ease of installation and future service. See Optional Equipment, this manual, for part numbers.
It may be recommended to use a back flow preventer
– check local codes. If a back flow preventer or a no return valve is used, a
thermal expansion tank must be installed on the cold water supply between the appliance and valve.
To control thermal expansion, a thermal expansion tank suitable for potable water should be installed in systems with an installed
backflow preventer. DO NOT use a closed type expansion tank. Follow expansion tank ma
nufacturer’s specifications to properly size an
expansion tank to the installation. Failure to properly accommodate thermal expansion could result in property damage, severe
personal injury, or death.
C. CENTRAL HEATING PIPING SYSTEM WATER PIPING METHODS
EXPANSION TANK AND MAKE-UP WATER
1. Ensure that the expansion tank is designed and sized to correctly handle system water volume and temperature.
Expansion tanks must be sized according to total system volume. This includes all length of pipe, all fixtures, appliances, etc. Failure to
properly size system expansion could result in wasted time, money, and possible property damage, personal injury, or death.
Undersized expansion tanks cause system water to be lost from the relief valve, causing make-up water to be added. Eventual
appliance failure can result due to excessive make-up water addition.
SUCH FAILURE IS NOT COVERED BY WARRANTY.
2. The expansion tank must be located
following recognized design methods. See expansion tank manufacturer’s instructions for
details.
3. Connect the expansion tank to the air separator only if the air separator is on the suction side of the circulator. Always install the
system fill connection at the same point as the expansion tank connection to the system.
DO NOT
install automatic air vents on closed type expansion tank systems. Air must remain in the system and return to the tank to
provide an air cushion. An automatic air vent would cause air to leave the system, resulting in improper operation of the expansion tank.
DIAPHRAGM (OR BLADDER) EXPANSION TANK
Always install an automatic air vent on top of the air separator to remove residual air from the system.
Use at least the MINIMUM pipe size for all appliance loop piping (connecting appliance to and from the primary/secondary connection).
DO NOT pipe the appliance in any configuration other than primary/secondary. All piping methods shown in this manual use
primary/secondary connection. This is to avoid the possibility of inadequate flow through the appliance. Using less than the required
minimum pipe size and piping in anything other than a primary/secondary installation could result in system problems, property
damage, and premature appliance failure. Such problems ARE NOT covered by product warranty.
Use both thread tape and pipe dope to connect to the 1
” heating water outlet and inlet.
Summary of Contents for EFTC-140W
Page 2: ...2 LP 520 REV 7 26 16 ...
Page 20: ...20 LP 520 REV 7 26 16 Figure 8 Water Pressure vs Flow Through the Restrictors 140W Models ...
Page 35: ...35 LP 520 REV 7 26 16 Figure 24 Piping Legend ...
Page 44: ...44 LP 520 REV 7 26 16 Figure 32 Electrical Wiring Diagram ...
Page 45: ...45 LP 520 REV 7 26 16 Figure 33 Ladder Diagram ...
Page 88: ...88 LP 520 REV 7 26 16 ...
Page 89: ...89 LP 520 REV 7 26 16 ...
