Getting
Started with the SLASH-D
This
guide is an introductory document for using the SolarLogic Assisted Solar
Heating Design website only. It is not
intended to be comprehensive. Users who
want training on the SLASH-D and the SolarLogic SLIC should sign up for one of
our trainings using the form available on the SolarLogic website: www.solarlogicllc.com.
The SLASH-D website works with IE version 8 or later, Chrome and Safari.
Overview:
1. Yellow boxes on the tabs
require an input. You must have yellow box entries for the calculations to be
proper.
2. White boxes are optional
inputs which can improve the calculated results for your job.
3. Grey boxes are calculated
output values.
Up Top:
1. Enter a Job Name and
a Tag. Use only alphanumeric
characters – no special characters. You
can then Save the job whenever you like as you are
working on it. The intent of the Tag is
to have different versions of the same job to compare as you look at options.
For example, tags might be things like “extra solar panels” or “no heat in the
garage” or “with spa”, etc.
Job tab:
1. State and City. Select the state and city
for your job (default: New Mexico, Albuquerque). This sets up the latitude and the 30-year
weather data (NREL data base) used for calculations. If there is no city available in your area,
use another city that you think is a good approximation to the correct latitude
and average coldest winter day.
2. Building Performance. Select the approximate UA
of the building by choosing from the building performance pull-down (default:
average). The UA that the SLASH-D uses
is displayed in Heat Loss Rate box. If
you have a calculated value for the building, select “Use Calculated Heat Loss
Rate” and enter that number in the white box labeled the same.
3. Comfort Target. Enter the temperature
at which you think the homeowner will want to keep the house, i.e., where the
homeowner will set the thermostats (default: 68).
Special Case Example: To use the Comfort Target
to compensate for not having a city nearby with the correct average winter
temperature. Santa Fe is typically 5-10
degrees colder than Albuquerque, but not far off in latitude or solar
resource (insolation). To set up the
SLASH-D for Santa Fe calculations, we choose Albuquerque as the city and set
the Comfort Target 7 degrees higher than we think the homeowner will
actually use, e.g., the default we would use is 75 instead of 68. This makes the building require a more
correct number of heating degree days for the calculations.
DHW tab:
1. DHW Usage. Input the daily gallons of
DHW use you expect (default: 50).
2. DHW Setpoint. Select the “shower
temperature” you want for the DHW tank, i.e., the water temperature below which
the boiler or other backup heat source should come on to make DHW (default:
120).
3. DHW Tank Capacity. If the job is a retrofit and you are keeping
the DHW tank, input the correct value (default: 50). If the job is new construction, or if you
intend on replacing the DHW tank as part of the job, a good place to start is
about 2 times the DHW usage. For
example, for a house with three people, enter 60 gallons for the DHW usage (20 per person) and 120 for the
DHW tank capacity.
4. DHW Tank Heat Loss. If you know something about the tank, you can
input what you believe is the accurate number for heat loss from the tank.
Otherwise, leave the default of 1 degree/hr.
5. Leave everything else at
default values.
Solar Components tab:
1. Solar Contribution. Choose the desired amount
of solar contribution to the annual combined space and DHW heating loads, from
low to high (default: medium). Medium
means that approximately 50% of the heating loads will be provided by
solar. The range covers from about 30%
to about 70%.
2. Collector Size. Select the collector size
you would like to use, thinking about mounting, roof space, etc. Larger
collectors can be more cost effective because of the cost of mounting hardware
and labor, but 4x8 is usually the least expensive in $/SF for the collector
itself (default: 4x8).
3. Platform Pitch. This is the angle of the surface on which
you will mount the collectors. A
flat roof is 0; a south facing vertical wall is 90. The default is 0 (Our
headquarters are in New Mexico). The
calculated horizontal separation is the required distance between
collector banks to avoid shading, from front to front, as measured along the
platform, if the collectors are mounted in landscape orientation. For
portrait orientation, use the vertical separation number.
4. Max Panels. This is the maximum number of panels allowed
in the first bank of collectors. This
maximum can be used to force the plumbing diagram to use two banks of
collectors if you want.
Manifold tab:
Note: On the Manifold tab, you only need to enter
one zone on one manifold to start off the calculations. You can thus do a really quick rundown of the
job by specifying the entire house as one zone, using the total heated square
feet.
1. Manifold Type, Circulators
and Tube Spacing. Choose the appropriate menu items for your job for each manifold
separately. “Circulators” is to choose
between using zone valves or zone circulators.
2. Zones. Enter each zone and its
square foot area. For radiant floors,
enter the number of tubing loops in the zone if you know it. For baseboard zones, enter the number of
baseboard linear feet and/or the number of baseboard plumbing loops if you know
them. The loop numbers and/or lengths
are used to calculate expected required flow for the zones. If you require a specific flow rate for a
zone other than what the program calculates, you can make the flow be a
different value by changing the number of loops to get the value you want. To delete a zone, blank out its name and then
enter 0 for the square feet. The zone
will disappear. You can swap zone numbers
via the zone number pull-downs on the left (even between manifolds).
Manifold G tab – this tab takes a bit more
explaining and is for outdoor pools, spas and ice melt zones. You can learn how
to use this tab in our trainings, particularly the Expert Training. Very briefly:
3. Ice Melt Zones. Use a nominal 1 gallon/min
for every 600 SF of ice melt for the flow required.
4. Spa. Choose the spa characteristics
and a flow of 5 gallons/min for a starting point.
5. Pool. You can put in the pool
volume and a nominal flow of 8 gallons/min, but the most important numbers for
a pool are the daily average heats needs in KBTU. These can vary enormously depending on the
pool size, shape, seasonal use and whether it is covered or not. The average daily heat use organized by month
needs to be approximately correct in order for the SLASH-D to calculate solar
panel sizing and tilt. These numbers can be gotten from your pool designer or
other specialist.
Congratulations,
you’re done!
Useful
Outputs (most outputs are self-explanatory):
1. Job tab:
a. Load Total – the total annual heating
requirements (MegaBTU, MBTU) for space plus DHW (this
includes pool, spa and ice melts if these loads exist).
b. Heated Sq
Feet –
check that you’ve got the right number of total square feet.
c. Leftmost graph – BTU Load versus
Resource. This graph displays the total
heat load in BTU/day by month (green), the solar resource (various colors) for
collector mounting angles from 0 to 90 degrees, and the solar resource (black)
for the selected collector mounting angle (either the SLIC-recommended angle or
the user selected angle if the recommended one is overridden.
d. Center graph – BTU Saved versus Panel
Tilt. This graph displays the total
annual BTUs saved (red) with solar (MBTU/yr) for
collector mounting angles from 0 to 90 degrees, and the total annual BTUs saved
(green) for the selected collector mounting angle (either the SLIC-recommended
angle or the user selected angle.
e. Rightmost graph – Dissipation versus Panel
Tilt. This graph displays the excess
heat needed to be dissipated on the worst day
of the year (largest difference between load and resource) in KBTU/day
(blue) for collector mounting angles from 0 to 90 degrees, and the needed
dissipation (green) for the selected collector mounting angle (either the
SLIC-recommended angle or the user selected angle.
2. Flow Center tab:
a. Plumbing diagram in block
form – each
block is detailed in another tab by the same name.
b. Parts list – only for the items shown
in detail on this tab.
3. DHW tab:
a. Recommended Heat Storage – the total number of
gallons required for heat dissipation, if necessary, and/or heat storage for
non-mass zones, if necessary. The actual gallons of storage used will override
this if you want. Use the “Storage Tank
Override” pull-down.
b. Plumbing diagram – for this part of the
system (one of the blocks on the Flow Center tab diagram).
c. Parts list – only for the items shown
in detail on this tab.
4. Aux Source tab:
a. Plumbing diagram – for this part of the
system (one of the blocks on the Flow Center tab diagram).
b. Parts list – only for the items shown
in detail on this tab.
5. Solar Components tab:
a. Recommended Number of Panels – this will obviously
change depending on several different choices you have made, including
collector size. The actual number of collectors used will override this if you
want. Use the “num
panels” pull-down.
b. Recommended Angle – for mounting the
collectors. This is the angle relative
to horizontal, not relative to the platform.
The actual mounting angle used will override this if you want. Use the
“angle” pull-down.
c. MBTU Saved per Year. An estimate of the number
of MBTUs the solar heating will save on an annual basis. This is NOT the number of BTUS the panels
will produce. It is the number of MBTUs
that will actually get used by the system, i.e., delivered to useful loads
throughout the course of the year. A
degrading factor for transmission and heat exchanger loss is included in the
calculations.
d. Plumbing diagram – for this part of the
system (one of the blocks on the Flow Center tab diagram).
e. Parts list – only for the items shown
in detail on this tab.
6. Manifold tab:
a. Plumbing diagram – for this part of the
system (one of the blocks on the Flow Center tab diagram).
b. Parts list – only for the items shown
in detail on this tab.
7. Manifold G tab:
a. Plumbing diagram – for this part of the
system (one of the blocks on the Flow Center tab diagram).
b. Parts list – only for the items shown
in detail on this tab.
8. Parts List tab – the accumulated list of parts from all the other tabs. The parts
list does not include ancillary items specific to the job, such as
copper tubing, PEX tubing, small fittings, adapters, mounting
hardware for piping and the collectors and glycol. It also does not include the
boiler. (We’re working on the pricing
section. Soon, you will be able to put
in and store your own pricing and have the SLASH-D come up with a real total
dollar estimate of parts for you. This
feature should be operational in the fall of 2012.)
9. Admin tab – you can change your password here at any time.