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Stylized Text: SWAP - Ten Years After.

The systems listed below were installed during the SWAP program that was conducted throughout Florida from 1994 through 1997. This listing provides information on the condition of these systems during inspections conducted between 2002 and 2004. The primary purpose of the inspection was to determine the operational status and condition of the systems.

Sites are listed below by various SWAP program areas in Central and South Florida.

Systems are identified as follows:

ICS = Integral collector storage system.
= Active direct systems using a flat plate collector and differential controller.
= Active direct systems using a flat plate collector and photovoltaic controller.
Timer = Active direct systems using a flat plate collector and timer controller.

The Operational column indicates whether the system is still operating. Note that in some instances, Unknown is listed. In these cases, the complete system was not inspected. Nevertheless, partial inspections or photographs provided noteworthy information therefore the system was included in this listing.

Each listing has a separate information sheet. Select a site from the list. The site page includes an inspection record and thumbnail photographs. Click on a particular thumbnail for a larger image. Once an image is selected, the viewer can then select either the Next image or Previous image or Home to return to that specific systems information site. Or, a viewer can also use the browser's (Internet Explorer or Netscape Navigator) toolbar Forward and Back arrows instead of the Previous, Home, and Next commands that appear when viewing the enlarged images.

In addition, a spreadsheet tabulation of all sites identifying problem items noted during the inspections is provided at the following site:

Tabulation of site and system specific categories (in PDF format)

See General Comments on the inspections below.

Site System Operational Comments
795 Diff No Control
800 Diff Yes Control set on permanent "on."
801 Diff No New tank. Disconnected solar.
802 Diff Yes  
803 Diff No Control
804 Diff Yes  
805 Diff Yes  
807 Diff Yes Leaks at tank. Poor install.
808 Diff Unknown Unoccupied
811 Diff Yes  
812 Diff Unknown No access.
814 Diff Unknown No resident. 70' pipe run.
815 ICS Yes  
816 ICS No New occupant. New roof. No solar.
817 Diff Yes  
821 Diff Yes  
822 Diff Yes  
823 Diff No Pump. Leak.
824 Diff No Pump
825 Diff Yes Suspect extreme scale in collector loop.
827 ICS No Diverter valve in wrong position.
828 ICS Yes  
830 Diff Unknown  
837 Diff No Control.

Site System Operational Comments
1 ICS Yes  
3 ICS Yes  
4 ICS Yes  
5 ICS Yes  
6 ICS Yes  
7 ICS No Collector leak. Owner isolated.
34 ICS No Collector leak.
36 ICS Yes Absorber repaired.
37 ICS Yes  
38 ICS Yes  
42 Diff No Not enough hot water. Isolated.
44 ICS Yes  
46 ICS Yes  
47 ICS Yes Replaced freeze valve (JH).
51 ICS Yes  
58 ICS Yes  
773 ICS Yes  

Site System Operational Comments
374 ICS Unknown Mounting problem.
375 Diff Yes Poor condition.
377 Diff Yes  
381 Diff No Tank replaced. System not reconnected.
383 Diff Yes Poor installation plumbing scheme.
387 Diff No Freeze damage to collector.
389 Diff Yes  
390 Diff Yes  
391 Diff No Freeze valve leaking.
392 Diff No Tank replaced. System not reconnected.
393 Diff Yes Freeze valve leaking.
395 Diff Yes  
396 Diff Yes  
652 ICS Yes Collector facing north.
653 ICS Yes Major mounting problem.
655 ICS Unknown Mounting problem.
656 ICS Yes  
850 ICS No Absorber leak.
853 Diff No Air vent leak. System isolated.
858 Diff No New roof. No collector.
864 ICS Yes  

Site System Operational Comments
16 ICS Yes  
17 ICS Yes  
18 ICS Yes  
19 ICS Yes  
20 ICS Yes System was isolated. Corrected. 
21 ICS Yes  
401 ICS Yes  
413 ICS Yes  
418 Diff No Collector leak.  
422 ICS Yes  
428 ICS No Client inadvertently isolated the system.
429  Diff No Collector leak.  
430  ICS Unknown Glass broken. No one at house. 
432 ICS Yes  
438 ICS Yes Freeze valve starting to drip. 
440 ICS Yes  
443 Diff Unknown No occupants. 
446 ICS Yes  
452 Diff No Collector leak.
453 Diff No Collector leak. Removed system. 
454 ICS Yes  
455 ICS Yes  Freeze valve starting to drip.
458 ICS Yes  
460 ICS Yes  
463 Diff No Freeze valve leak.
464 Diff Yes  
468 Diff No Collector leak.  
474 ICS No Collector removed. New roof.
475 Diff No Collector leak.  
476 ICS Yes  
478 ICS Yes  
479 ICS Yes Freeze valve starting to drip. 
484 ICS Yes  
486 Diff Yes  
488 ICS Yes  
491 ICS No Freeze valve leak. Isolated system. 
493 Diff No Collector removed.
495 Diff No Collector leak. Removed system. 
496 ICS No Freeze valve failed. Isolated system. 
497 ICS Yes  
500 ICS Yes  
501 ICS Yes  
505 Diff Yes  
508 ICS Yes  
516 Diff No Collector/pipe leak. 
526 ICS Yes  
529 Diff Yes  
530 ICS Yes  
532 ICS Yes  
533 Diff No Collector leak.  
535 ICS Yes  
538 ICS Yes  
693 ICS Yes  
695 ICS Yes Inner glazing loose. 
698 ICS Yes  
699 ICS Yes  
703 ICS Yes  
704 ICS Yes  
709 ICS Yes  
784 ICS Yes  
790 ICS No Exterior pipe leak.

Site System Operational Comments
22 Diff No Removed
23 Diff No Collector
24 Diff Yes  
25 Diff No Removed
26 Timer No Timer, check valve
28 Diff Yes  
29 Diff No Control, check valve
30 Timer No Valve, unoccupied
31 Timer Yes  
32 Diff Yes  
33 Diff No Pump, outlet
34 Timer No Removed
64 PV Yes  
68 Diff No New tank. System not reconnected.
75 Diff Yes  
81 Timer No Timer and pump defective.
91 PV Yes  
95 Timer Unknown  
103 Timer Unknown  
118 Diff Yes  
125 Diff No Control
131 Timer No Timer, check valve
145 Timer No Air vent leaking
154 Timer No Timer defective.
164 Diff Yes  
170 Timer No Timer defective.
195 Diff No Control
220 Diff Yes Shade problem.
233 PV Yes  
247 Timer No Timer
249 Timer No Removed
258 PV Unknown No contact
265 PV Yes  
269 Diff Yes  
288 PV Yes  
292 PV No Pump
293 PV Yes  
300 PV  Unknown No contact
319 PV Yes  
723 Diff Yes  

Site System Operational Comments
343 ICS No Leak in absorber.
345 ICS No Absorber removed.
348 ICS Unknown Possible leakage.
351 ICS No Leak in absorber.
361 ICS Unknown  
370 ICS Unknown  
658 ICS Unknown House unoccupied.
659 ICS Unknown House unoccupied.

General Comments

1. Systems should be kept as simple as possible. Certain systems that require client interaction are not recommended for this type of program.

2. Solar systems require periodic inspections and maintenance. The more complex the system (complex being more components) the more this applies. A large majority of problems were related to a variety of valves that required service and or replacement. The majority of low-income clients will not (cannot) expend funds to have systems maintained or components replaced even though the maintenance or repair charges are relatively minimal.

3. Agencies promoting and funding low-income solar programs should set aside funds for future maintenance and repairs. Otherwise their investments in these systems will be for naught once a component fails and the client isolates the solar system. Even if they do not fail, certain components have a set lifetime and should be replaced prior to that period.

4. A number of collectors were discovered to have failed, both flat plate and Integral Collector Storage (ICS). Contact with the flat plate manufacturer indicated that the majority of these failures were caused by a poor header/riser connection design which has now been resolved. The ICS manufacturer in turn had received some absorber materials that were not manufactured properly and led to leakage problems. During the standard warranty period, the manufacturers provided coverage for replacement or repair of defective absorbers. Unfortunately, many low-income clients did not contact anyone, but simply shut the system down whenever a problem occurred. Once the standard warranty period expired and the limited warranty took affect, the clients were then responsible for the labor portion of repairs. Because of this burden, once again many clients chose to deactivate the system instead of paying for labor charges. In many cases, the local weatherization agency used other funding sources to cover the labor fee for the clients. In other cases, the local weatherization agency informed the client that the SWAP program had terminated and that there was nothing they could do.

5. Exterior pipe insulation (and insulation coatings) was a major problem. Exterior insulation, due to the harsh external environments, requires periodic maintenance and re coating or replacement. It was discovered that in cases where the installers affixed metal foil tape over the piping insulation, the insulation was still intact. It is recommended that metal foil tape be used in future low-income solar programs – as well as in general installations.

6. A large number of air vents were observed to have either failed by leaking, or having the exhaust port sealed by scaling. Air vents are extremely susceptible to sedimentary scaling – especially in areas where water chemistry are ideal for this condition. Scaling buildup eventually seals the air vent’s exhaust orifice and also appears to affect the internal mechanism, leading to leaking air vents.

7. Problems with freeze valves led many clients to isolate their collector loop and therefore sacrifice the use of a solar system. These valves are used to prevent freeze damage in soar collectors. Their lifetime appears to be in the seven to ten year range and should at least inspected and /or replaced before this period. ICS systems would preclude the use of these valves if the correct piping and pipe insulation were used. This plastic bodied valve also incorporates a section of metal that was observed to have been rusting severely in many instances.

8. Anti-scald valves, while beneficially providing scald protection in the active pumped systems – especially where older and very young persons reside - were very susceptible to scale buildup within the internal parts of the valve. A large number of valves were stuck at a certain setting. This did not affect the performance of the valve – at that setting – but instead precluded any future adjustment. (Note that the clients had been informed to exercise the valve periodically, but in reality, people do not have the inclination to do this.)

9. Other than a few instances, the various controllers used proved to be quite reliably. Differential controllers had a few problems, but overall, the majority of theses controllers and their associated sensors appeared to have functioned quite reliably. The photovoltaic controllers appear to be the most reliable of the control methods used. Unfortunately, this was not the case with the timer controllers. Once again, the timer is a component that needs periodic client attention (periodically checking the set times and replacing the batteries). Inspections revealed that few timer systems were still working. In addition, clients had not periodically checked their timer or the timer’s backup battery.

10. Installation craftsmanship, in many cases, left much to be desired. Although all systems were installed by Florida licensed contractors, the knowledge of system installation methods and trade skills - as well as use of industry standard practices and material - varied widely from installer to installer. This was quite evident in all aspects of the installations - sealing of roof penetrations, securing sensor wiring, use of rust resistance materials, etc. Membership in the solar industry needs to be looked at as a professional trade – with it’s required skills.

11. Water heater failure was observed in numerous installations. These were conventional water heaters that, although part of the overall solar system, are also components that are required for heating water regardless of whether there is a solar system at the residence or not. Therefore, the water heaters cannot be seen as a “solar” component that has failed but instead as part of the overall water heating system. (Although higher solar temperatures may accelerate the eventual failure of the tank.) The majority of failures were due to leaks in the water heater – either from the internal tank of from fitting joints at the top of the tanks. When water heaters failed, the person or company replacing the water heater did not reconnect the solar system. It appears that neither the client nor those replacing the water heater understood the significance of the solar system.

12. Overall, most clients did not have any problems with having a solar system. A few even understood what the function of the system was and that it saved them money. Others were completely ignorant of the system and had to be informed what the "skylight" on the roof was for. A more thorough education program needs to be conducted in future low-income programs. Also, those receiving solar systems should have a commitment to that system. In turn, funding agencies should implement some type of long term maintenance program.


The number of instances discrepancies and notable negatives were identified during the inspection process – per system.

Item Instances
Insulation 60
Air vent 30
Collector 28
Freeze prevention valve 26
Sealing 23
Anti-scald valve 22
Wiring (exterior) 16
Tank (water heater) 15
Control 12
Mounting (collector) 12
Pressure relief valve 11
Piping (exterior) 11
Flashing (exterior) 8
Piping (interior) 8
Isolation valve 6
Insulation (interior) 6
Pump 6
Ceiling penetration 6
Wiring (interior) 5
Sensor (exterior) 2
Check valve 2
Drain valve 2
Disconnected (for unknown reasons) 2

It should be pointed out that system inspections were conducted at random during visits to respective geographical areas. Investigation was not conducted to try to determine what caused specific problems. What is noted above is what the inspector was able to determine from a visual and brief physical inspection of the system. For instance, once it was determined that a controller was no longer working, this was not followed up with an investigation of what made the controller fail. When air vents were leaking, or their exhaust ports calcified, the cause of the problem, possibly being water with an extremely high mineral content was not investigated. Neither was the effect of high temperatures and the acceleration of calcification. The cause of the freeze valve problems was not determined. Suffice it to say that the valves reached their lifetime expectancy. A survey of numerous solar installation companies does reveal that indeed the valves do last only x number of years - which corresponds with the observed field failures.More than anything, it appears that he vast majority of the low-income clients do not quite understand what they have and instead of maintaining and servicing their systems, they would rather sacrifice the system, and future savings, than expend funds to have the system repaired even when minor problems arise.