Solar hot water collectors on house in Maryland.
These panels provide heat and hot water as well as heating for a future
hot tub.
Images of heat exchangers. The top one transfers heat
from the panels to the storage tanks (below). The lower one transfers heat
to the domestic hot water system (pictured second image down). A zone valve
(to the left) controls which heat exchanger gets the water flow.
Heating and cooling water is stored in two 275 gallon
oil tanks located behind insulation. The antifreeze solution (propylene
glycol) is stored in the white tank which is a standard water heater with
auxiliary tappings. The two pumps pump the glycol up to the panels on the
roof and it drains back into the tank after going through the heat exchangers
pictured above.
Piping arrangement on the domestic hot water tank. The
circulator pump (pictured below) drives water through the heat exchanger
(2 above) from the bottom of the tank to the dip tube (near pipe). These
pipes will all be insulated in the future to prevent energy loss.
Domestic hot water circulator pump moves water from the
bottom of the tank through the heat exchangers and back again.
Image of the heat pump unit. This heatpump provides heating
when the solar panels do not provide enough heat in the winter as
well as air conditioning in the summer. There is also a domestic hot water
coil called a desuperheater that removes the heat from the compressor motor.
That heat goes into another tank (pictured second below)
Heat-pump anti freeze loop to the outdoor fan coil unit.
The expansion tank is necessary to maintain pressure on the loop so the
pump won't cavitate.
Domestic hot-water tempering valve prevents occupants
from getting burned by water that can reach in excess of 180 degrees F.
on a hot day from either the solar panels or the heatpump.
Outdoor fan coil unit used to transfere heat from the
air to the fluid. If the owner ever decides to go to a ground source heatpump
system this will be ready to go.
The owner rewires the electrical controls to accommodate
the new hot water loop. The house water storage tanks are on the left behind
the insulation, the glycol drain down storage tank is to his left, the
heat pump is under the control box and the orange box in the upper right
hand corner is a differential controller that runs the pumps to the collectors
depending on the difference between the buffer tank and the roof.
Back to top
