Criterion 6.1.6.3 Insulation

Criterion text:
All interconnecting hot water piping and the final 1.5 meters (5.0 feet) of the cold water supply pipe leading to the system, or the length of piping which is accessible if less than 1.5 meters, shall be insulated with R-0.46 oK m2/W (R-2.6 oF-ft2-hr /Btu) or greater insulation.

All exterior piping insulation shall be protected from ultraviolet radiation and moisture damage.

Comments:
Insulation has a tremendous impact on restricting heat loss in the various system components. Nowhere is this more critical than in the pipe insulation since system piping is the transit means for solar heated liquid.

The manufacturer's SRCC approved installation manual specifies the type and thickness of insulation that is to be used. It is critical that the installer follows the manufacturer's instructions.

Installers must make sure that all piping is insulated. This includes all external piping as well as required interior piping. It also includes proper butting of insulation at termination points, making correct miter cuts at angle joints, and ensuring that the insulation is well sealed. Very often, installers overlook small sections of piping adjacent to various valves - usually in the tank plumbing area. Although it is quite tedious to cut and attach insulation to these small areas, it is nevertheless very critical in reducing system heat loss.

Once the insulation is installed, it must be protected from ultraviolet ray degradation with an approved insulation coating.

The following photographs chronicle good and bad insulation installation practices.

System piping in Figures 1 and 2 has been well insulated. Note that the installer has also secured the insulation with black tape. The insulation is butted to the tank and cutouts have been made to accommodate the various valves.

Figure 1

Figure 2

Contrast the installations shown in Figures 1 and 2 with that shown in Figure 3. Note that in Figure 3, the installer did not complete the tank area piping insulation task. These small piping areas may be tedious to insulate, but are critical in reducing overall system heat loss.

Figure 3

Note in Figure 4 how the installer has installed the insulation around the isolation valves and maintained a tight and well insulated seal.

Figure 4

Long pipe runs are very easy to insulated. Just slip the insulation over the piping and pull it along. Understandably, small sections of piping - end sections, butted sections, and angle sections - present their own unique problems and are usually insulation tasks that are not properly completed. Installers need to take the time to correctly insulate these areas.

Small sections of piping (Figure 5) need to be insulated in the same manner as longer easier to insulate sections. This type of work does not leave a good impression or instill confidence in the installation on the part of the the customer.

Figure 5

In order to provide properly sealed insulation ends, installers should consider the use of escutcheons at ceiling penetrations (Figure 6). This also greatly affects the aesthetics of the installed system. Compare Figure 6 with Figure 7.

Figure 6

Figure 7

Special care must be taken for outdoor pipe insulation. Installers must use the proper type of insulation for exterior applications. In addition, the insulation must be protected from ultraviolet ray degradation.

Figures 8 and 9 reveal what happens when the wrong type of external insulation is used. In this case, plastic insulation was used. Only rubber insulation should be used for external applications. Plastic can be used for internal cold lines but nothing else. Follow the manufacturers installation instructions and acceptable industry standards and materials.

Figure 8

Figure 9

Exterior insulation must be protected from degradation by ultraviolet rays with some type of coating or jacket. In the case shown in Figure 10, the installer is coating the insulation with an ultraviolet ray protective paint provided by the manufacturer. SRCC reviews and approves applicable coatings.

Figure 10

Without properly protecting the insulation with an ultraviolet ray resistant coating, the insulation will quickly degrade. The insulation shown in Figure 11 was coated three months previously with a non-ultraviolet ray resistant coating and already exhibits deterioration.

Figure 11

Figure 12 shows a well insulated piping bend. Note that the installer has not only mitered the ends, but has also affixed an insulation glue compound to keep the two separate sections together.

Figure 12

Figure 13 shows how not to complete an insulation run. The section should have been mitered (See Figure 12). Not only will this leave the insulation and piping exposed, but it will also allow water to drip down the piping between the pipe and insulation.

Figure 13

The insulation installation in Figure 14 will also lead to future problems by creating pools where water can accumulate and possibly seep into the structure.

Figure 14

Installers should also make sure that insulation is installed on system piping runs in the attic. (Figure 15)

Figure 15

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