John Wood Tankless Review
Consider the following facts and
tips when selecting the best John Wood
tankless water
heaters for on demand heating of potable water in residential and light
commercial applications. The article reviews the top features and
benefits of the
combined on demand and condensing technology.
Top Features and Benefits
High efficiency
All
the John
Wood water heaters designed for on-demand water heating are
using Takagi
technology. Models that utilize
the
condensing technology are ultra-efficient
models that come with two heat exchangers; one made of commercial grade
copper and second made of the stainless steel, making the units
resistant to the aggressive water action.
Such a combination
allows the usage of the latent heat from the flue gases for the high
thermal
efficiency of over 90%. Non-condensing series consist of the
conventional models that are able to provide an
energy factor of 0.82 and 0.83.
Flexible venting
With the higher thermal efficiency, especially those models
with the energy factor in the range from 0.91 to
0.95, water heating costs are significantly reduced. Also,
the products of combustion have the lower temperature, which allows
venting with the approved PVC, CPVC and PP pipes,
for added flexibility and lower costs. The venting system is
flexible as it can be installed as the two-pipe system or coaxial
direct vent, horizontally or vertically.
Fast delivery
For homes where the higher demand is needed with the stable
temperature and fast delivery, .... you can use the FlowTHRU
storage tank that is
specifically designed to work with John Wood tankless water heaters for
added comfort. For the
supplemental heating, FlowTHRU storage tanks are
equipped with one
electric heating element, an adjustable thermostat and side connection
to a circulation pump.
Advanced electronics
The condensing water heaters feature the advance electronics
that provide easy temperature adjustment right on the built-in screen,
diagnostics and features
that help prevent scalding burns, also the advanced safety features
such as the internal freeze protection system.
All the condensing units are using the advanced features such
as the self-diagnostic system for safety and your
convenience. The integrated controller allows you not only to change
and monitor the temperature of hot water, but check other parameters
and also error codes if the problem exist. On non-condensing units, the
error code
will show up on the remote controller and computer board.
-
Warranty - 12 years.
-
Direct venting with the sealed combustion for
indoor models available. -
Maximum exhaust vent piping length is up to 100 ft.
- Convenient automatic ignition.
-
Safety: thermistor and hi-limit switch for the exhaust
gas, freeze protection... -
Some models use Easy-link up to 4 units without multi-unit
controller (510 and 540 H models only). - Multi-Link connects up to 20 units into one system, so the
power can modulate from 13,000 to 4.0 million Btu/hr. -
240, 340 and 540 series are condensing models.
- Ultra Low NOx models are available.
-
Recirculation pump control mode available on 510 water
heaters. -
Temperature adjustment from 100 to 140 F, or 100 to 185 on
540 H models.
Model selection
Specifications - Technical Data
| Models --- Specifications |
BTU Min/ Max |
Efficiency EF |
Flow Max GPH |
Temp Min/ Max F |
# of baths |
Remote / Controller |
| JWT-240H-N | 15,000 160,000 |
0.95 | 6.6 | 99 167 |
2 | Yes |
| JWT-320H-N | 13,000 180,000 |
0.91 | 8.0 | 99 167 |
3 | Yes |
| JWT-340H-N | 15,000 180,000 |
0.95 | 8.0 | 99 185 |
3 | Yes |
| JWT-520H-N | 10,300 180,000 |
0.91 | 9.0 | 99 167 |
4 | Yes |
| JWT-540H-N | 15,200 152,000 |
0.96 | 10.0 | 99 167 |
4 | Yes |
| JWT-110-N | 19,500 140,000 |
0.82 | 6.0 | 99 167 |
2 | Yes |
| JWT-310-N | 11,000 190,000 |
0.82 | 8.0 | 99 167 |
3 | Yes |
| JWT-510-N | 11,000 199,000 |
0.82 | 10.0 | 99 167 |
4 | Yes |
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(The pictures are courtesy of John Wood website)
