Boiler water fills, and is circulated through, the ERGOMAX tank, thus eliminating
the potential for scaling and corrosion, ensuring that the ERGOMAX/boiler combination
will always operate at maximum efficiency. Turbulence is also created within the
ERGOMAX tank to maintain an ideal environment for heat transfer.
When demand for hot water occurs (eg. a faucet is opened) cold water enters
ERGOMAX's coils and is heated as it flows through the them in a turbulent manner.
This turbulence scours the inside of the coils flushing out any potential scaling
that could occur, keeping the coils clean.
ERGOMAX has a limited lifetime residential warranty, and commercial limited
warranty is 10 years.
ERGOMAX technology, thermal storage and turbulence, results in many benefits:
Frequently Asked Questions about Ergomax®
What is an ERGOMAX? ERGOMAX is a heat exchanger,
popularly known as an indirect water heater.
What is an indirect water heater? An indirect water
heater is a heat exchanger and uses heat from an external source (i.e. a boiler,
solar panels, etc.) to heat the cold (domestic) water.
How does a direct-fired water heater differ from an indirect?
A direct-fired water heater has its own firebox and must be vented to the outside
(like a boiler) and creates its own heat. It operates independently of other equipment.
Which is better -- direct or indirect? Indirect
(heat exchanger) is more efficient and will produce more hot water (from the same
amount of heat) than a direct fired unit. (It also has no flue.)
What makes ERGOMAX different? ERGOMAX are different
from other indirects in three ways:
- Tank is filled with boiler water, and domestic water flows
through a bundle of copper coils.
- Turbulence is induced in the boiler water in the tank and
in the domestic water flowing through the coils.
- Domestic hot water is not stored; it is heated instantaneously,
Why do other indirects scale up and corrode? Other
indirects hold domestic water in the tank and heat it by immersing a coil connected
to a boiler in the tank. The heat from the boiler water in the coil heats the
domestic water in the tank. As hot water is used, fresh cold water enters and
refills the tank. This constant refilling of the tank with fresh water provides
a steady supply of minerals which precipitate out when the water is heated and
attach themselves to the hottest part of the tank -- the coil -- forming a constantly
growing layer of scale, reducing the heat transfer from the hot boiler water to
the cold domestic water. Also, the constant temperature swings within the tank
from hot to cold cause the tank (steel) to expand and contract. These thermal
stresses cause cracks to form in the glass lining(which does not expand) allowing
the steel to be attacked by oxygen in the water, causing corrosion.
Why won't ERGOMAX scale up or corrode? The ERGOMAX
tank is filled with boiler water. So, except for a very small
amount of makeup water, no new minerals or oxygen enter the tank. No minerals
means no scale build-up; and no oxygen means no corrosion.
ERGOMAX tanks do not need glass lining as they hold boiler water, and thermal
stresses are minimal as ERGOMAX operates on the same temperature differential
as the boiler. Also, turbulence within the ERGOMAX tank prevents stratification
and cold spots.
How does turbulence affect energy consumption? Energy
consumption is reduced because heat transfer is much more efficient within a "turbulent"
environment than within a "static" environment.
How is turbulence maintained within the ERGOMAX tank?
A mechanism located at the top of the tank forces the incoming boiler water
to flow in spiral formations throughout the entire tank, creating turbulence.
How many coils does an ERGOMAX contain? The last
digit of each model number represents the number of coils in that unit, so:
- Model E23 has 3 coils
- Models E24 & E44 have 4 coils
- Models E45 & E65 have 5 coils
- Model E109 has 9 coils
Why are all ERGOMAX coils 50' long regardless of model?
Coils of this length have maximum heat transfer with minimum pressure drop.
How many GPM can each coil handle? Each ERGOMAX
coil can handle 3 - 3½ gpm on a continuous basis. Peak usage can go as high as
4-5 gpm per coil, but this output rate should not be steady-state.
How is turbulence created within the coils? The
total cross section area of all coils is less than the cross section area of the
incoming pipe, causing the domestic water to flow faster within the coils and
creating a turbulent flow (eg. like a wide river flowing through a narrow gorge).
Why is turbulence inside the coils important? Turbulence
inside the coils scrubs the inside of the coils, preventing formation of scale.
How does turbulence affect heat transfer? Turbulence
creates an ideal environment for heat transfer. An example will illustrate this
phenomenon: You come home very tired and want to soak in a very hot bath. How
do you get into the bath? Very slowly, not to cause any ripples. Once you are
in the bath, you can lie in this very hot water so long as you do not move. When
you start to move, you feel the heat. This movement creates turbulence which "washes
away" a thin layer of water next to your skin (known as a boundary layer) which
acts as a layer of insulation preventing heat from the rest of the bath water
to get to your sk in. Similarly, turbulence within the ERGOMAX tank and coils
prevents this boundary layer from adhering to the inside or outside of the coils,
hindering the heat transfer process
What is an ERGOMAX unit's heat transfer efficiency?
ERGOMAX units operate at 99%+ heat transfer efficiency which stays constant over
Why is ERGOMAX 99+% heat transfer efficiency higher than that
of other indirects? ERGOMAX is much more efficient because the built-in
turbulence inside and outside the coils creates an ideal environment for heat
transfer. Also, ERGOMAX copper coils transfer heat at a much higher rate than
other metals. Other indirects, using coils made from other metals which conduct
heat at a lower rate, operate in the mid to low 80% range when new, and steadily
lose efficiency as they scale up over time.
What is thermal energy and how does an ERGOMAX unit store
it? Thermal energy is heat. The hot boiler water in ERGOMAX tank contains
heat (Btu) which is used to heat the incoming domestic cold water.
How does thermal storage translate into energy savings?
Thermal storage allows the boiler to run less often, saving energy. When domestic
hot water is needed, the heat stored in ERGOMAX tank (hot boiler water) is used
to heat the cold water entering the coils. When the demand for hot water uses
up all of this stored heat, the boiler is activated to supply more hot boiler
water to ERGOMAX tank to continue heating the domestic water. This makes the boiler
run less often. Combined with the built-in turbulence, this capability results
in minimal energy consumption to heat domestic water. The thermal storage in ERGOMAX
also acts as a buffer to minimize/eliminate short- cycling in low mass boilers
during periods of low demand.
How much domestic hot water is stored in each ERGOMAX unit?
Very little, each coil holds less than 1/3 of a gallon.
What is the recovery rate of an ERGOMAX unit? With
ERGOMAX, there is no need to worry about "recovery," because an ERGOMAXunit will
never run out of hot water as long as the boiler/circulator are functioning and
hot water demand does not exceed the boiler's capacity to produce heat.
What equipment comes with an ERGOMAX unit? All units
come with an aquastat, a 30 psi ASME safety valve, and a drain valve. E24 through
E109 models are also equipped with a temperature/pressure gauge.
What is the tank made of? Is it glass-lined? AS36
steel. A glass lining is not needed since the tank contains only "dead" boiler
What maintenance does a ERGOMAX unit require? None.
Does ERGOMAX have a sacrificial anode rod? No. None
is needed as no fresh water enters the tank (it holds only "dead" boiler water).
Does an ERGOMAX need a separate flue? No. It has
no firebox and produces no exhaust.
Does an ERGOMAX unit make any noise? No. Normal
operation is completely silent. If any noise, vibrations or gurgling is heard,
there is probably some air trapped in the piping or the tank. Open the safety
valve until all of the air is evacuated. NOTE: Installing an automatic air vent
on the tank will prevent trapped air from accumulating at the top of the tank
and causing corrosion.
What is the tank standby loss? Less than 1/2oF
Can water conditioners, antifreeze, etc., be used with ERGOMAX?
How long is the residential warranty? ERGOMAX are
covered by a Limited Lifetime Warranty to the original purchaser, which can be
transferred to the second owner during the first 10 years following installation
(see the Warranty). Note: Residential use is considered to be a single home or
How long is ERGOMAX warranted in commercial applications?
Ten (10) years, 100% for the first 5 years, then prorated 20% in each of years
Legionnaire's Disease has been traced to domestic water systems
and, in particular, storage tanks where stratification occurs. Can such bacterial
growth occur in an ERGOMAX? No. ERGOMAX does not store potable hot water,
but heats it only as it is needed, instantaneously, so no bacterial growth can
occur in ERGOMAX. NOTE: The ideal temperature for bacterial growth in a traditional
indirect units, direct fired units or storage tanks is 120oF.
Does ERGOMAX come in a double-wall version? No.
ERGOMAX is exempt from the BOCA and IAPMO double-wall requirements. Under
BOCA, heat exchangers utilizing non-toxic heat transfer fluids are exempt
from the double-wall requirement. (See BOCA - 1993 Edition, Section P-1507-13.2).
Under IAPMO single wall heat exchangers are permitted, so long as
a) the heat transfer medium is either potable water or a substance recognized
as safe by the FDA; and b) the pressure of the heat transfer medium is less than
the operating pressure of the potable water system. The ERGOMAX tank is filled
with boiler water at low pressure. The higher domestic water pressure will cause
the safety valve on the ERGOMAX tank to open should a leak from the coils into
the tank occur.
Can ERGOMAX units be used with "low-mass" boilers? Yes.
Since the ERGOMAX tank is filled with boiler water, it acts as a buffer and prevents
low-mass boilers from short-cycling.
Can ERGOMAX units be used with "cold-start" boilers?
Yes. However, as with other indirect units, if a reverse acting aquastat is installed
in the boiler it will prevent boiler water from circulating into the ERGOMAX tank
until the boiler water is up to temperature. This allows the boiler to "catch
Can ERGOMAX units be used with steam boilers? Yes,
but only with low pressure steam boilers. By tapping in below the water line on
the boiler (at least 9 inches below the water line), hot water can be drawn off
to supply the closed loop to the ERGOMAX tank. NOTE: Care should be taken not
to draw any sediment into the ERGOMAX tank from the bottom of the boiler.
Information Source: ErgoMax