 Avoid hang-time, attach ladder to gutter nail using piece of wire Solar collectors at Amazon |
Review
solar water heater Solar water heater review Applies to recirculation type system Electric solar PV panels not covered here... but some information applies Search waterheatertimer.org
/
all results
Search using
  
|
 Cirrex with electric back-up 800-443-2545 Includes solar pump station, 2-3 collector panels, 80-120 gallon storage tank, and plumbing for heat transfer fluid. Other materials not included are expansion tank, air vent at top of circulation loop, drain pan, pipe insulation, discharge line from TP valve, mixing valve, additional drain valve on circulation loop, etc |
1)
Collect solar heat
using
2-3 panels located on roof of house. 2) Electric pump circulates
distilled water
or propylene glycol from solar panels into large tank. 3) Solar heat is
transferred into water using a heat loop or heat exchanger located
inside tank.
Is a solar water heater worth the investment? .... depends on cost of system and other factors... read more Rule of thumb: Don't buy expensive water heater that you cannot maintain yourself: Applies to solar water heater, heat pump, hybrid, tankless, condensing etc.. All costs and decisions are energy. Keep it simple. Consider all costs Federal Residential Renewable Energy Tax Credit is worth 30 percent of the cost, including labor and installation costs of a solar water heater. So your system net cost might be 12,500 less 30% = $8750? for a water heater that lasts 12-14 years AO Smith Solar Sell sheet Solar manuals DIY solar collector 2'x2' Read about new federal water heater energy standards |
|
Pipes are oversized in this illustration... actual pipes are smaller,
and amount of fluid is small Storage tank has 1 element for back-up heat Tank has heat loop coil built into tank The collector loop is closed, and is filled with antifreeze or water that does NOT mix with water stored inside tank Bottom element port usually has temperature sensor mounting plug. Tank has 1-2 ordinary anode rods that are cut off short so they do not touch solar heat loop Otherwise tank is typical electric water heater with anode rod, dip tube, thermostat, electrical connection. See |
Closed
loop recirculation design, reviewed here, some say...
'provides most reliable source
of hot water vrs other
commercial designs' Recirculation design uses pump to circulate distilled water or glycol. Recirculation system requires electricity to run 30 watt, 1/25 Hp motor Different system or do-it-yourself system may fit your situation better than this design... but this design is generally most reliable for producing hot water. Every locale and situation is different. Every budget is different. Circulate heat-transfer fluid/ or circulate water into storage tank AO Smith Cirrex uses non-toxic freeze-protected heat-transfer fluid. Fluid will not freeze down to -30°F in some conditions. 100% Propylene Glycol mixed 50/50 with demineralized water. Propylene Glycol prevents water from freezing Heat transfer fluid contains corrosion inhibitors. Not corrosion proof. Do NOT use tap water... only demineralized or distilled water. Water-based system: Water systems will freeze and must be drained in freezing weather. Water does not contain corrosion inhibitors. Water that circulates must be treated to prevent deterioration of closed circulation system One back-up element Typical storage tank for recirculation system is 80-120 gallons and has 1 back up element located in upper element port, typically ordinary 240 volt, 4500 watt element available local store. Voltage AO Smith manual says: Solar water heater will work with 'one voltage only'... do not connect to any voltage other than voltage listed on rating plate located on side of tank Condensation/ drain pan required Solar tank will have condensation. Insulate pipes can reduce condensation. TANK must be set in drain pan with 3/4" line going to appropriate drain |
| The conversation below is between 2
people in 2015, compares PV electric vrs glycol collection system and
is not comprehensive of all people's experience and may not reflect
prices and results in your area. Information from local users is best source. Q. $28,000 for PV photovoltaic solar water heater? That's high. I assume the price was not DIY?... and price included batteries, inverter, everything normally associated with converting DC to AC. A. It was for a PV electric system installed package that didn't include batteries. The government tested the FP panels I got independently for SRCC rating and from their rating mine produce 21,450kW per day after inefficiencies which should translate into a 6700 watt PV hot water system. Per the government most PV systems people install are 4kWh with an average price of $32,500 per install. My coworker has a 16kWh system he did and it was $86,000. My other coworker is getting a PV system over $40,000 on his house. PV is spreading like crazy here because they don't pay for a dime of it: with the state incentives + the installing company sells the excess and leaves the homeowner paying for nothing in the end. My state I think is going to go bankrupt if they keep this up. Commentary: PV photovoltaic provides electricity to entire house... not just water heater. PV has come down in price from $4-5 per Kw to near $1 per Kw 2015 with 20-25 year warranty on power output. Read the warranty on any solar product carefully. product and installation have different warranties. Different parts have different warranties. Glycol system: Q. Are glycol solar water heating incentives still in effect? A. I did the 3 panel glycol system with 120 gallon tank and after buying it got around $3,500 back from incentives. To see if there's solar incentives for your state (Federal should be 15% on entire project) you can check out http://www.dsireusa.org/ Q. After incentives, can I ask what was final cost for your glycol system 5 years ago in 2010. I assume the installation was not DIY? A. $3,000 after incentives. Total $6500 up front 5 years ago. It's a DIY kit, has everything needed to DIY except pipe (pick up at local store), fittings, and insulation. Total cost after incentives was just under $3,000 for everything and I mean everything. But, $1000 of it was for electrician and plumber because in my state you have to be licensed to do any electrical or attach to drinking water. Q. Approximately what area of world do you live? Warm climates favor glycol circulation collectors? While cold climates favor PV energy collection because hot panels casuses less output? Windy location favors PV electric because it cools panels, while windy location is not best for glycol collector because it cools panels. A. Yes cold PV panels produce more electricity. I live in the cold parts of Massachusetts (far away from Boston). Cold doesn't affect my solar glycol much, just wind. It can be -5F and sunny and my solar glycol will have the bottom of my tank over 120F. If 20F and very windy I can expect around 90-100F. Even so that's the very bottom of my 120 gallon tank. My solar is designed since we have 2-3 days of clouds/rain a week typically one day of sun and my solar turbo heats enough water for 2-3 days of coasting. Mine is not meant for day after day of sun, though it includes overheat protection. Q. An important price consideration is durability... Glycol systems last about 12-14 years? And that lifespan includes collection panels and storage tank... the entire thing. While PV electric panels last about 25 years? But that doesn't calculate replacement of storage tank, batteries, etc for converting to DC to AC. A. There's 2 kinds of Glycol systems I suspect you're thinking of the evacuated tube kind. Flat Panels are strictly made of glass, copper, and aluminum and the lamination technology binds the coating to the aluminum so it can't delaminate. If you saw todays Flat Panels you'd have a hard time finding any thing that can fail before 40 years, just the fluid running in the pipe over decades causes the pipe to get thinner and thinner and eventually it will fail. My house has original copper pipes and is 1962 and they're still going should be more than 50 years. Q. I would estimate the cost comparison between glycol and PV is about 1:1.6. So if glycol system lasted 1 year... the PV system would last 1.6 years. Total cost comparison should consider this? A. As mentioned I see no reason why a glycol FP system would fail within 40 years. The reason I chose FP's was because my in-laws have a solar house from 1983 with factory made FP's (not home made of wood, screws, see-through fiberglass, etc.). So far in 32 years they have had to replace a pump which was easy enough, otherwise their solar FP's are still going strong heating their house and hot water. Commentary: Soldered copper joints exposed to constant temperature change might not last as well as indoor copper pipes. There is no 40 year warranty. 12 year warranty is standard. (compare 25 year for PV electric panel). Product warranty and installation warranty are usually separate. Some parts may have different warranty than other parts. Solar water heater tanks are probably not going to last 40 years. There are products that out-perform expectation if anode rod is changed and native water supply does not have heavy mineral content. Panels lasting 40 years: Cool region that only gets sun 1 out of 3 days like areas of Mass, the panels will probably last longer than intense-sun states like Texas. Technology is always changing. Government website shows 12-14 year lifespan for glycol product. Note: The anodes may not bet standard for your tank. Certainly they must be shorter so they do not come in contact with solar loop, and generally two anode rods are used. Q. Glycol system generally must be located near to water heater, for example on rooftop. A. All the solar installs here the water heater is in the basement and we run glycol pipes up to the roof through the panels and back into the basement. Attics here are ventilated to prevent ice dams so attics are typically the same temp as outside which can get below 0F... terrible place for a water tank Everyone puts them in the basement and pipes the glycol up through the panels on the roof. Commentary: Pumps must match the load. More elbows and distance increase friction in the line. 85 watts, 110 vac is standard. They also sell DC pumps (3 watts) for regions like Hawaii that are connected to a 10 watt PV panel, but there is no switch or thermostat to control it. The pump works faster when the sun is hot, but slower on cloudy days or not at all at night or extremely cloudy. Q. PV panels are more numerous and can be located farther away... on the ground... but greater distances causes more power loss... and PV panels consume a lot of space if located on the ground. A. You can put hydronic anywhere as well it's just pipe (though must be copper). PV system does take up a lot of room I calculated one would need a 24 panel PV (420 sq ft system) to heat as well as my 3 panel glycol (96 sq ft). Commentary: More distance = more heat loss along length of glycol pipes. Do not assume your location requires 3 panels. Estimate of 24 PV panels does not specify the Kw rating of each panel. For example they make 100 Kw and 270 Kw panels Q. PV electric systems must accommodate resistance changes as solar output changes... while glycol systems just heat or don't heat depending on solar output?. A. In short you can do PV, not saying it won't work just that it's almost certain you'll end up with a lot more parts, complexity, price, space, and failures sooner than the alternative. Commentary: PV has more parts and complexity. PV supplies electricity to entire home, and not just water heater |
|
 See detailed illustration |
Solar water heating seems
simple Can be complex. Cleaning Maintenance Freeze prevention unless unit is glycol Pump Storage tank Heat exchanger Seasonal temperatures Secondary heat source Damage to roof Insurance coverage Storms, lightning Trees Resale of home Local codes Expected life vrs future Replacement cost Part replacement |
 |
Solar loop inside water heater can be single-wall or double wall |
 Larger image Review solar water heater Solar water heater review Applies to recirculation type system Electric solar panels not covered here... but some information applies Another image |
Solar water heater can be
complex & expensive Solar panels integrated with gas water heater and tankless. Tankless uses solar heat to preheat incoming water. WHY make a system so complicated? It cannot save money. BUT tankless cannot be easily integrated with other heat sources Solar water heater can produce 180 degree water midday on hottest day. Special tank is needed to handle expansion, or mixing valve to add cold water into pipes. Water confined to a storage tank or piping system, when subjected to a temperature rise of 10°F (increasing from 75° to 85°),increases pressure from 50 psi to 250 psi 180 degrees is very hot. Storage tank must be well insulated. If the system recycles water continually, then the 180 degree water will only be available for short period of time, and water cools quickly once it circulates outside the insulated tank. Other parts not shown: Solar Pump Tankless circulating pump Air vent Vacuum relief valve Bolts drilled through roof etc. How does that save money? Payback 25-35 years Resource: How to save hot water using mixing valve |
| NO magic water heater... reduce consumption is best
answer.
I prefer ordinary electric water heater since it can be repaired and maintained DIY to last forever using simple generic parts. But new energy standards 2015 will change the landscape. Read about new energy standards Numbers on chart below may not be most current information for your area. Cost of maintenance and repair not included  |
|
Payback depends on total cost
Typical saving might be $12-20 per month depending on many factors |
Payback
depends on total cost Payback $12-20 per month maximum Use this page to help research total cost of solar system. Use this page to consider other factors. Are you going to use back-up electric heat elements? Or go off-grid? When do you consume hot water? Morning, evening? Or afternoon? Maintenance, parts, repairs, warranty, people with similar system in your area, cloudy days, wind, shade, storms, local codes etc |
||||
 Solar collector made from plastic bottles |
|
||||
 |
Try
small DIY do-it-yourself solar collector
Recirculate water from panel into small water heater Buy Solar collector at Amazon 2x2 panels at Amazon Resources: Compare small water heaters |
||||
 |
Experiment PV solar panel powers pump/ solar panel heats water Must use water filter and air vent when connecting to plumbing system Do the homework.... make sure PV panels and pump work together.... make sure pump will circulate the water enough distance This pump will probably not work with long distances... use 120 volt pump Use any water container... not necessary to connect to water heater Filter the water using hose washer... innovate Buy Solar collector at Amazon 2x2 panels at Amazon Pump at Amazon Resources: Compare small water heaters Water heater terminology and formulas Water pump information |
||||
 |
Heavy-duty
recirculation
pumps at Amazon/ solar systems use pumps Use recirculation pump for DIY solar Works for any recirculation system or solar project 120 volt, 1/25 HP, 30 watt New line of lower Hp pumps introduced by Grundfos for PV solar-power homes. PV is photovoltaic... where solar panels produce electricity Buy Grundfos recirculation pump at Amazon Cast iron flange set for flanged pumps Resource: Compare recirculation pumps |
||||
 PV solar voltaic produces electricity System is not being reviewed here |
Photovoltaic electricity/
not a recirculation system
Can photovoltaic DC electricity be connected directly to water heater? Maybe. Electric Solar panel connected to electric water heater Ordinary water heater elements will work with DC power BUT water heater thermostats will melt with DC power So why not control thermostats with DC power See wiring diagrams to run AC water heater on DC solar Quote: "a photovoltaic water heating (PVWH) system requires neither a battery for energy storage nor an inverter to convert the DC power supplied by the photovoltaic array into an alternating current (AC) power. The DC electric power supplied by the photovoltaic array is fed to one or more resistive elements that are immersed in a water storage tank." The quote suggests connecting PV panel directly to elements, without using thermostats But you can control thermostats with low voltage DC power Read about this option Buy from my associate links: Elements at Amazon DC Element at Amazon Resource: How to convert AC water heater to DC / high voltage How to convert AC water heater to DC / low voltage |
||||
  |
Easier
ways to save money? 3) There are many low-cost ways to save with a water heater, including behavioral changes. Reduce consumption. Insulate pipes and water heater. Maintain water heater. Do not turn on hot side when using cold. Read 9-ways to save with water heater How to maintain water heater |
||||
 Solar water heater collectors near water heater Requires 2-3 panels to circulate water into storage Proper tilt angle for solar collectors is latitude plus 15°. Performance suffers little when collector oriented no more than 45° East or West of True South. Compare: with photovoltaic array  Photovoltaic array uses more panels, produces electricity, panels located on ground, can be further from home Larger image |
Resale
of house/ appearance 4) Call real estate agent about solar rooftop systems. Agent can tell you if solar must be removed before resale Some areas, solar will increase resale value of home Appearance of home can be altered with panels and pipes. Visit another home with similar solar installation. Solar investment is not mobile If family moves frequently, can you afford to invest in expensive water heater? Local codes 5) Contact permit board to see what permits are needed. Local neighborhood may not permit solar panels. Reason, solar panels on roof can detract buyers or attract buyers depending on market. Solar collectors on roof Usually the recirculating solar system [being reviewed here] requires 2-3 collectors located close to storage tank. 2 panels for Hawaii. 3 panels for less temperate regions. Proximity to water heater is important so small pump can circulate the water. Rooftop installation not required... but hot water rises, so elevating panels above storage tank is better. PV electric collectors on ground PV electric systems usually require more collectors, or more panels, but collectors can be on the ground farther away from water heater. PV electric loses power when more distance is added. Use larger wire for panels located farther away. On average, PV systems last longer than solar thermal systems. PV lasts about 25 years. PV system works better in cold weather than warm weather. Reverse of recirculation systems. |
||||
 |
Lightning/Storms/High winds/ 6) Do you have lightning rod? Copper pipes and metal on roof attract lightning Use lightning rod system in areas where lightning is common. Risk of lightning is higher when home is near pond, high elevation, or sitting alone. Higher structures or multiple structures nearby, will reduce lightning risk. Lightning within 100 feet can damage any home not protected by lightning rods. Lightning safety Move indoors and do not stay on roof, or move metal ladders, or touch anything made of metal when lightning is within 1 mile or can be heard or seen. Baseball/ Tornado/ water leaks/ are additional risks Resource: How to install whole house surge |
||||
 |
Ground
wire/// this information applies to all water heaters and appliances All solar system must be grounded. Check local electric codes. What does this mean? Drive ground rod 8-10 feet into soil. Bond #6-8 bare copper wire to ground rod and to solar panels and pipes on roof. Do NOT ground electric system to water pipes. Ground must be connected to ground rod. Stray current corrosion can cause pipes to deteriorate. Uncertain bond to ground because of plastic pipes. Buy: Ground rod and clamps at Amazon Bonding lugs Bond all ground wires together to help prevent surge & lightning damage Bonding all grounds together will help prevent damage from lightning strikes beyond 100' away... Strong lightning strikes within 100 feet must be handled by lightning rod Local code requires bonding: this includes all ground rods for satellite, TV, phone, solar, electric panel, subpanels (within 100 feet) etc must be connected together and bonded to main electric panel ground rod driven into soil at correct depth to meet local code. Consult local electrician. Codes for grounding depth vary: loose rocky dry soils are less conductive than dense wet soils No system other than lightning rods will protect against direct lightning strike or strike within 100 feet. Move indoors and do not stay on roof, or move metal ladders, or touch anything made of metal when lightning is within 1 mile or can be heard or seen. |
||||
 Old ropes are NOT safe Always use new ropes. |
Maintenance 8) Ask seller and installer about required maintenance. Maintenance is required. Solar panels do not clean themselves. And solar panels are located on roof. Dirty solar panel will absorb less heat. Trees, leaves, roof repairs Do NOT believe salesman who says no maintenance needed Can you maintain the system yourself? Can you find somebody locally who can maintain the system? Do not buy complex systems if local area does not have affordable, experienced service people. Roof leaks We occasionally fixed roof leaks caused by solar panels Contact local roofing company and ask their experience Roof replacement If roof needs to be replaced, then work has to take place around panels This increases cost, chance of leak, damage to panels |
||||
 Move indoors and do not stay on roof, or touch metal ladders, or touch anything made of metal when lightning is within 1 mile or can be heard or seen. |
Insurance-Liability 7) Call insurance company and ask if homeowner insurance covers external solar panels. Do you need special insurance? Are the installers insured? Who will repair and maintain system, how much will it cost, and are you covered from liability? If you are climbing on roof once each year to clean solar panels, what is cost of one broken leg? Ladders Do you have to buy ladders? Take apart extension ladder, and you have 2 ladders We use two aluminum ladders chained together to climb down sides of roof. Best way to get on roof is along the pitched side. Set ladder at angle, as illustrated with wooden ladder, so both ladder feet are flat on ground, then set ladder at angle until both rails are flat against roofline. This is counter-intuitive to set ladders this way, but very effective and safe. We also used ropes to secure ladder from falling over, we also made one ladder leg longer on aluminum and wood ladders by adding stout 2x4 or 1x4 yellow pine. When setting ladder against gutter... use wire to tie ladder to gutter nail. Set bag of dirt behind ladder feet. When setting ladder on grass or dirt, turn the feet so they stab into soil. Dig small holes for feet. Choose grass-dirt over concrete surface when setting ladder. Never set extension ladder on wet concrete, or concrete that slopes away from ladder. Sweep surface clean. Never set extension ladder on tile surface without full bracing behind feet. Higher person climbs, less stable ladder. Always make sure 4 points of ladder touch... 2 feet firmly at bottom and 2 rails firmly at top |
||||
 |
How
to check extension Ladders Extension ladder has several parts: 1) Rung locks, 2) anti-slip safety feet, 3) Slide rails, 4) Base rails, 5) Rungs etc Do not use ladder that is bent. Check the bolt that connects rung lock to ladder. Look for cracks in aluminum rail... add fender washer to strengthen Check if bolt is bent excessively. Must use hardened bolt. Always check that rung lock is over both rungs. ALWAYS make sure both rung locks are in place. Treat your ladder like it was airplane... you are the pilot... inspect plane BEFORE flying Buy: Ladder replacement feet with hardened bolts Aluminum ladder leveler for uneven ground Safety step ladder Ladder parts and stabilizers at Amazon |
||||
 Galveston 2015 |
Solar
panels block sun from hitting roof Solar panels on roof will reduce temperature of roof in winter Attic is cooler in winter. Furnace runs more Warm attic helps keep house warm for many hours after sun sets in winter climates Tropics Tropical climates such as Malaysia and Hawaii might benefit from reduced solar on roof, while homes in Indiana might not benefit |
||||
 |
Wind Windy location will cool the glycol solar collector. Result less solar heat/ less hot water circulates into storage tank Manufacturer's glossy brochure does not consider heat loss from wind Compare: PV photovoltaic panels, that produce electricity, benefit when wind cools the panel Wind damage Surprisingly, panels located on ground are more susceptible to wind damage and wind effect from many directions |
||||
 Use new pipe Use as few elbows as possible Keep solar panels close to water heater |
Distance
between collector and storage tank Locate collection panels as close as possible to storage heater. Longer distance means loss of efficiency when pump is circulating water, and loss of heat along length of pipes. Heat travels upward, so best if panels are located above storage heater. |
||||
|
Number
of elbows Number of elbows and bends in pipe affect efficiency of recirculation pump. Use long sweep elbows. Diameter, condition, distance, and configuration of pipe effects overall efficiency Prevent electrolytic corrosion/ deterioration of galvanized pipes and clogs. Use brass and stainless when connecting copper and galvanized pipes. Use 6 wraps teflon tape on threads Buy: Brass nipples at Amazon Brass elbows at Amazon Stainless nipples at Amazon Stainless elbows at Amazon Resource: Water pump and pipe distance information |
|||||
 |
Heated
water and sediment deposits All heated water leaves behind mineral deposits. Higher temperatures, and harder water cause more deposits. Water heated in excess of 140° will percolate many minerals out of water Heated glycol does not leave behind deposits in the collector. Water circulation system will leave behind deposits in the collector and heat exchanger. Storage tank and heat exchanger can become coated with sediments using either water or glycol system Treating hard water costs money Water softener may be required, or other water treatment. For example, a conventional electric water heater can be used without water softener because elements can be replaced for $12, and tank cleaned out inexpensively. The solar collector and solar heat exchanger are not as easy to clean as ordinary electric water heater. Consider cost of water treatment. Anode rod. All metal tanks require anode rod to prevent tank from rusting. Includes solar tank. Water softener causes anode to deteriorate faster. Read about anode rods |
||||
| Prices |
Price: Total
price
must include installation, anticipated maintenance, parts, repairs,
expected life of unit, depreciation or appreciation on resale value of
home 9) Ask for the total price up front. Ask if glossy literature showing huge savings also includes cost of running circulating pump, cost of maintenance, cost of repairs, and cost of system replacement in 12-14 years. (Hint: glossy brochures do NOT include these costs) All costs are energy Look at the parts sheet. What do replacement parts cost? Who carries the parts 5 years from now? Who is going to climb roof and clean solar panels Does insurance cover solar panels Do you have lightning rod to prevent major damage caused by lighting coming down copper pipes on roof Are you going to sell house? |
||||
| Payback 25-35 years |
Payback
25-35
years? Do the math. If the system costs $4000-6000 and saves year-round average $15-20 per month, then it will take 300-400 months to pay back, or 20-30 years. Do not believe promotional claims that show savings more than $15-20 per month. Your actual savings will be less than $15 per month, depending on how hot water is consumed. |
||||
| Go full solar/ no back-up |
Payback
10 years if you go full solar and no water heater expense 10a) If you accept solar-only hot water, then you can save full cost of water heating... for example save $400-600 per year, then payback is quicker. Do it yourself solutions are cheaper, and maybe best for you |
||||
|
Who covers warranty?
Manufacturer, seller, installer? Probably You !! |
Warranty You know the problem. Call for warranty never returned. Buck is passed You paid for system and paid the installer before the system was tested at your home. Make sure it works before you pay: Test drive the car first. Get references, do not strike deal where seller and installer get paid before the system checks out 100% equal to promise. Which means you better do the research and compare against similar installations IN YOUR AREA before buying expensive solar water heater. Be a negotiator. If they want your business. And they are truthful about saving money at your home ... then they can wait to be paid. Get it in writing. |
||||
| High Temperature at high noon |
High
Temperature at high
noon 11) Solar can reach temperatures of 180° midday summertime, assuming solar panels are clean Ordinary water heater temperature is 120-135° Residential electric water heater thermostat range 90-150°/ commercial thermostat 120-180° See residential and commercial thermostats This high solar temperature is only available at peak solar heating, and not during hours when you usually consume hot water. The very hot water from noontime continues to circulate through solar collector, and cools during this circulation unless temperature sensors stop the circulation pump. All tanks lose heat to standby... just like cup of coffee cools. Adding insulation will benefit all tank-type water heaters: residential, commercial, storage, indirect, tempering, gas, electric, oil, solar, geothermal |
||||
| Water cools rapidly |
Water
cools
rapidly 12) Solar heat dissipates very quickly. Test this yourself with 1 gallon water left in sun. Once fully heated, put gallon inside insulated picnic cooler located next to water heater and check temperature 1 hour later, then 5 hours later. Is the water still warm? Is it hot enough to use for shower? Probably not. Pour it on hand to gauge temperature. |
||||
| Take showers early evening, and do not wait between showers |
Shower
instead of bath extends solar heat Shower uses 5-9 gallon hot water. Bath uses 12-15 gallon hot water. Oversized bathtub, and spas are 'against the law' when considering energy-saving. Shower is much more economical than bath in general terms... economic factors vary when two or more people bathe simultaneously by candlelight with lights and TV turned off. When hot water is run from tank, then cold water immediately enters bottom of tank, causing tank to cool more rapidly, or causing electric element or gas burner to fire up. To consume solar hot water, it is best to consume all the collected hot water at once with several showers in quick succession, before tank cools. This applies to off-grid applications that use only solar, and do not use fuel to heat water. Resource: How much hot water does bath or shower use |
||||
| Time and temperature |
Most
hot water
consumption at night or morning, after solar heat is gone 14) Consider: If you consume most hot water in late evening or early morning, the solar-heated water will be dissipated at those times, and water is being heated by conventional fuel. This means solar heating system is only saving standby cost during daytime hours. Standby cost is small, and does not warrant expensive solar heater. When hot water is consumed during late evening or early morning shower, new cold water immediately enters tank and the new cold water must be warmed by conventional fuel. Heating incoming cold water is biggest factor in water heater cost, so if no hot water is being consumed at peak solar output, then water heating cost is minimally solved by using solar. EXCEPTION: large 80-120 gallon solar water heater that was fully heated during day to temperatures in excess of 140-150. The tank is well-insulated, and located in naturally warm spot. The circulation pump stopped circulating when tank was fully heated at maximum temperature. The system is working right. The hot water was not consumed accidently by water leak. Mixing valve was added to top of tank to sip hot water and keep cold water from entering tank (described above), etc. |
||||
 |
Key
thing for solar water heat is Make-when-it's-there and
Sip-it-when-it's-not
Add mixing valve to save hot water. Important for solar. Also for regular tank. Solar tank gets very hot during good solar day. You do not want super-heated solar water for shower. Mixing valve located at storage tank can be set to correct temperature for shower. Mixing valve automatically adds cold water to the line so temperature of shower is correct. How does mixing valve save hot water? Remember, a mixing valve is exactly what you do during shower to keep temperature from being too hot... you add cold water to hot. So each faucet; bath, kitchen, shower and tub faucet is a mixing valve... where you manually adjust water temperature by adding cold Each time hot tap is turned on, cold water immediately enters bottom of water heater as hot water leaves top of tank going to shower.. When you use mixing valve located at water heater instead of mixing valve located at shower, then you save the amount of hot water that travels down the pipe going to shower. How much hot water is saved? Every 10 feet of 1/2 pipe holds .12 gallons of water. If bathroom is 20 feet away. 3 showers per day .72 gallons per day x 365 days = 262 gallons of cold water that does not enter tank. The math is more complex than this 2-D example. But a mixing valve keeps more cold water out of tank, and water heater stays hotter Buy from my affiliate links: Mixing valve kit at Amazon Water heater mixing valves at Amazon Resource: How much hot water does bath or shower use |
||||
|
Special tank needed Ordinary tank not rated for solar heat? |
Solar
tanks are made for high heat / solar
temps can reach 180°
Solar tanks are large: 80-120 gallons/ Let's you store hot water so it is available later Residential water heater thermostat range is 90-150°/ commercial thermostat range 120-180° See residential and commercial thermostats Ordinary residential water heater tank cannot be repeatedly exposed to 180° temperatures without causing damage to tank. Residential tanks come with TP valve that releases water at 150°. Exception Marathon heavy-duty with 5 year tank warranty is rated 175° Solar water heating tanks, and many commercial water heaters are rated for temperatures equal to 180° This mean solar requires special tank, and/or tempering valve that moderates temperature entering tank Specialized parts are needed Absolutely be aware that 180° temperatures can cause immediate life-threatening burn. |
||||
|
Full solar/ off
grid/
Unpredictable hot water supply |
Full
solar
without backup fuel 15) If home is using only solar to heat water, and no back-up fuel source is used, then solar system will save full cost of operating water heater. But ordinary 120° hot water temperatures will not be available each day, or available all hours of day. Off-grid full solar rations hot water to yourself Basically the all-solar strategy saves money by reducing consumption, which you can do without buying expensive water heater. Why install expensive water heater just to ration hot water to yourself, when a water heater timer, or DIY solar collector can do exact same thing for less cost? |
||||
| Summer |
Summer is best
for solar... but also best for ordinary tank 17) Solar works better in summer ... but so does ordinary water heater. Ordinary water heating energy bill in summer months is much lower because incoming water temperatures are warmer. This means water heater does not have to raise temperature as much to reach thermostat set point. Summer months are best for solar water heater, but they are best months for conventional water heater too. See family charts Add a tempering tank to preheat incoming cold water during winter See passive tempering tank |
||||
| Winter |
Winter
without
much solar heat 16) Solar water heaters will not generate much heat in winter in non-tropical regions. How many months long is your winter? How many cloudy days vrs sunny days? Southern Indiana winters are cloud covered. Check weather almanac Check weather archives for average temps, and understand that 'average high temperature' in winter might be 40, but the high temperature only lasts 1 hour of the day. |
||||
| Winter preparations? |
Winter
preparations? Requires planning and work 18) Ask if the system must run full-time in cold weather to prevent freezing. Or if you have to drain system. What are maximum low temperatures for equipment. How sluggish is the glycol when very cold? Will freezing temperatures affect wires and connections? If the system has non-freezing glycol, what is low temperature limit, and what will happen if there is a leak on roof. Ask if the system has automatic system to keep cold water from entering tank. If system must circulate full-time to avoid freezing, then cold is circulating inside tank, and tank must use conventional fuel to warm the cold water. If the system has a heater, ask how much power the anti-freeze heater uses. Do you have to drain the system each winter? If the solar heating pipes must be drained each winter, can you do the work? |
||||
| Call others in same area with same installation |
Call
other people in same area that have same
equipment. Ask if you can visit their location and see how their set-up would differ from yours. For example if they are in sheltered valley and you are windswept hillside. Wind will cause solar collector to average cooler temperatures |
||||
| Parts |
Parts:
Look at
parts sheet, ask about replacement parts 19) Ask to see parts sheet to estimate general complexity of system. Don't look at parts shown on glossy brochure, look at the replacement part list. If there is no parts sheet available how are you going to get parts? Do you want to become a solar water heater expert. Web search the parts before buying. There are all kinds of experts out there, each more knowledgeable than the next.. Maintenance and repairs are major factor in calculating costs. All costs are energy. Ask about expected lifespan of each component part. Ask which parts you should have on-hand in case of breakdown. |
||||
| Part replacement |
Part
replacement
20) Pumps, and other parts can become expensive to buy and repair. Ask for price sheet for each replacement part, and ask who will carry the part when you expect part will fail. Can you do the repairs yourself. Who is available in your area to climb on roof and do repairs? In winter during snowy month. |
||||
| Lifespan |
How long will the system last?
Do you really think it will last 13-20 years? Can you afford to buy another system a mere 13 years from now when prices are double or triple? Maybe prices will be the same? Maybe new local methods will be the answer? How long will you last? Can your remaining spouse handle replacement installation, repair, maintenance, etc associated with rooftop solar collector over the expected lifespan of product |
||||
 No particular reason why things happen ? |
 |
||||
|
Cleaning solar panel/
maintenance Can you make repairs and do the maintenance? Trim tree limbs, wash panels, clean off leaves and debris, patch roof leak.. Do you want holes and pipes on roof? Does insurance cover roof and solar panels injury? Some day the solar heater will need to be replaced ... which is why most home resales require removal of solar system. There is no standard checklist for appraiser or inspector to check solar system. While you're up there... Tuck point the chimney Coat the top with sealant Buy: Crown saver chimney coating |
 Yes I've done this
Old ropes are NOT safe Always use new ropes. |
||||
|
Passively preheat incoming
cold water Use old water heater as tempering tank. Set tempering tank in naturally warm location How to recycle water heater Which is best gas water heater How to install gas water heater How to install electric heater Increase amount of hot water Add another thermostat to water heater |
 |
||||
 |
Buy Electronic parts Industrial supplies Tools and home improvement Home and garden Hayward pool Pentair pool Southwire electric |
 |
Buy
Tools DEWALT Black and Decker Stanley SKIL Makita Porter-Cable Bosch Irwin Hand tools Klein hand tools Fluke electrical testing Dremel hobby tools Campbell Hausfeld air powered Tekton automotive Powerbuilt automotive Saws and saw blades |
 |
Resource: Compare box timers DPDT timers Intermatic Control water heater w/ Z-wave |
 |
Resource: Intermatic control centers: and parts Digital control centers and parts Tork control centers and parts Subpanels All control centers and parts Enclosures |
 |
Resource: Programmable timers Countdown timers Off delay timers On delay timers Timer modules Din rail Twin & one-shot Woods Intermatic Tork |
 |
Recirculation systems |
 | Buy
from my affiliate links every time/ thanks: Amazon As an Amazon Associate I earn from qualifying purchases Enter Amazon from any link on my site, fill cart with any item ... purchases pay small commission E-mail: geno03245w@gmail.com My response might end up in spam folder, check email folders Waterheatertimer on Twitter Message thru facebook |
