When I designed and built a house for my wife and me in the
late '90s, she gave me one instruction: "I don't care what it
looks like, I just want it to be warm." Both of us had grown up
and lived in "antique" houses infused with charm — and
frigid drafts. We wanted to be comfortable in our new
home.
The house would sit in a field, in a valley noted for high
winds. The design was straightforward, a contemporary
interpretation of a story-and-a-half farmhouse. But there were
some twists: 48 windows, an open floor plan downstairs, and
three bedrooms, two baths, and a central hall upstairs. Mix in
a collection of family antiques to be placed against exterior
walls, and the challenge of choosing a heating system robust
enough to keep up with northern New England winters while
occupying minimal wall space becomes apparent.
Choosing a Heating System
I also wanted a simple system, to keep maintenance costs down
and because I planned to do much of the installation myself. I
ruled out some systems immediately: electric baseboard, because
it costs too much to operate in our climate, and hot-water
baseboard, because it takes up too much space along outside
walls, where we planned to place furniture. I also decided
against forced hot air, which requires labor-intensive ductwork
and, in my experience, is drafty and heats unevenly.
I took a close look at radiant floor heating. But my heat-loss
calculations showed that I would need supplemental hot-water
baseboard, so I nixed that idea. Radiant heating can also get
costly because of the amount of PEX tubing required, as well as
the need for mixing valves to lower the temperature of the
water coming from the boiler.
High exposure.Loaded with windows and sitting in a
windy valley in northern Vermont, the author's new house had
the potential to be cold and drafty. He chose hydronic panel
radiators, which have provided even, comfortable heat through
the first four winters. Panel radiators operate in the same
range of temperatures as hot-water baseboard, but take up less
wall space for a given Btu output.
A magazine ad led me to panel radiators. These compact
wall-hung units promised to deliver the required Btus, could be
flexibly located to work with furniture layout, and would
connect to the boiler with easily installed polyethylene
tubing. Panel radiators operate at the same high temperature
output as hot-water baseboard, so there's no need for
additional mixing valves to lower the water temperature, as
with radiant floor heating. Another benefit of panels is that
they are simple to zone, by connecting two or more together in
the same circuit and fitting one with a TRV, or thermostatic
radiator valve — a reasonably priced nonelectric control
valve. For example, if we wanted to keep the master bedroom
cooler than the system operating temperature of 68°F, the
bedroom's three panel radiators could be looped together and
controlled by a single TRV, which would lower the room's
temperature by restricting the amount of hot water flowing
through the radiators. This in effect would create a separate
zone in the bedroom.
System Components
One of the nice things about building your own home is that
you can try new techniques without having to convince the
client. After researching panel radiators, I was sure they were
the right choice. I wasn't really taking any risk, because they
have been used successfully in Europe for years.
Panels. The radiator I
selected is made by Veha, a Belgian company, and distributed in
the U.S. by Windy Ridge Corp. (800/639-2021,
www.veha.com). Most of the information you
need to select and price the panels can be found right at the
website. Panels are available in two thicknesses and many sizes
to match the heating needs of various spaces. Besides the
standard radiators I chose, you can get flat-panel radiators
that double as towel warmers. The radiators come standard with
a baked-on white enamel finish and can be professionally
painted if you want other colors.
Veha isn't the only manufacturer of panel radiators. At least
three other European companies, Buderus, Myson, and Runtal,
have American distributors. They all offer similar products
with various individual features, and all offer towel warmers
(see "Panel Radiator Manufacturers" at the end of the
article).
Boiler. I chose a Buderus
G115 (800/283-3787,
www.buderus.net), a
cast-iron boiler from a company with a reputation for
high-quality workmanship. I went with the direct-vent option to
avoid the expense of a chimney. I capped the exhaust vent with
an aerofoil cowl to minimize the effect of head-on wind blasts.
A fresh-air intake pulls in outside air rather than consuming
basement air. On the advice of my plumber, I added a Stor-Ex
(800/221-1522, www.dhtnet.com) indirect water heater off
the boiler for domestic hot water.
What could be simpler?The heart of the heating system is the
Buderus direct-vent boiler. The primary loop feeds the indirect
hot water tank and the main heating manifold, which supplies
hot water to secondary manifolds upstairs.
Controls. The brains of the
heating system reside in a small blue box that sits on top of
the boiler. The Ecomatic HS2105 (which has been superseded by
the Logamatic HS2107) controller establishes a weekly heating
schedule. It comes with nine factory-set heating programs that
can be altered to suit personal preferences. It also
automatically changes operation from winter to summer and
controls domestic hot water production. Permanent memory of all
program settings after power interruption guarantees that
instructions do not have to be reset. A manual override switch
allows temporary bypassing of the settings, while an LED panel
provides information on current program settings as well as
optional choices.


Controllers.The Buderus boiler control unit (top)
senses outdoor temperature changes and signals the boiler
accordingly. It also allows for flexible programming to fit any
schedule. Heat zoning is effectively provided by equipping
individual panel radiators or groups of radiators with a
thermostatic radiator valve (bottom).
An outdoor sensor sends temperature readings to the controller
so the boiler "anticipates" a call for heat. For example, if
the outside temperature suddenly drops 20 degrees, the
Ecomatic, which is programmed to expect a drop in temperature
indoors as well, fires the boiler in advance to maintain a
constant room temperature.
PEX tubing. Rather than use
rigid copper tubing, I chose to use Kitec PEX-AL-PEX (Ipex,
800/463-9572, www.ipexinc.com), a type of PEX tubing that
has a thin layer of aluminum laminated between two layers of
polyethylene. The aluminum stiffens the tubing so that it
retains its shape after bending (unlike standard PEX tubing,
which springs back and must be clipped in place at frequent
intervals). The presence of the aluminum also greatly reduces
the thermal expansion and contraction of the tubing compared
with standard PEX, which moves, sometimes noisily, as it heats
up.
Flexible piping.Tucked away in upstairs closets, the
manifolds (top left) distribute hot water to several "zones"
— individual radiators or groups of radiators. The Kitec
pipe cuts easily with a plastic pipe cutter (top right). The
compression fittings require no special tools other than a
simple reamer (above).
I purchased the manufacturer's compression fittings (crimp
fittings are also available), which simplified installation.
The connectors tighten with wrenches and come in a variety of
configurations to transition to threaded and sweat fittings. I
also needed two manifolds, which I bought from Ipex, configured
with compression fittings.
I bought three sizes of tubing: 3/4-inch for connecting the
boiler output to the system's two manifolds (one on each
floor), 5/8-inch for connecting the first-floor panels to the
first-floor manifold, and 1/2-inch for connecting the
second-floor panels to the second-floor manifold. PEX-AL-PEX
comes in 100-foot, 300-foot, and 1,000-foot rolls, so it's easy
to make "home run" connections without any intermediate
couplings.
Installation
The Veha panel radiators hang from four L-shaped nylon
brackets, which are lag-screwed to the wall. The location of
the mounting rail on the back of the radiator varies according
to the radiator's size, so to speed layout I made a cardboard
template for each of the five sizes of radiator I used. I made
sure I had a stud or solid blocking for the brackets before the
drywall went up.
I made similar templates to locate the supply and return line
holes in the floor. (Panel radiators can be piped through the
wall, but getting all the components — radiator and
fittings — to line up is difficult.)
I spent two days pulling tubing (I have eight zones) and about
two hours each hanging the radiators and making the connections
to the PEX-AL-PEX. Setting up and piping the boiler, expansion
tank, and circulators, as well as running the stainless-steel
exhaust hosing, took about a week. A heating contractor spent a
day hooking up the oil tank, connecting the Ecomatic
controller, and firing up and testing the system.
I isolated each of the components — boiler, hot water
tank, circulators — with shutoff valves so I can do
maintenance as needed without draining or shutting down the
entire system. I also added a low-water cutoff to shut off the
boiler if there's a leak, and a mixing valve to make sure the
domestic water temperature never exceeds 120°F.
Performance
We originally set the heating cycle to the Ecomatic's "family"
setting, which pumped hot water through our system from dawn to
midnight. This proved unnecessary because of our schedules, so
we switched to the "single" setting, which supplies us with
heat when we need it: early morning and late afternoon through
the evening and throughout weekends. The change reduced our
fuel bills noticeably. Nine settings are available to match
various lifestyles.
I've been through four heating seasons now and have hardly had
to fine-tune the system. Other than changing the program
settings, the main adjustment has been to learn where to set
the nonelectric thermostatic valves on the radiators. For
example, the two smaller bedrooms are used for overnight
guests, so we keep the heat shut down in those rooms until they
are needed.
We like the looks of the panel radiators: They're unobtrusive
and blend in with the furnishings. The house heats evenly, with
less than a 2°F variance throughout. And I have yet to
hear a complaint from my wife about being cold.
Lee McGinleyis a builder in Addison, Vt.