Criterion 6.1.3.2 Tank Insulation

Criterion text:
Except where required by system design or constrained by safety considerations tank insulation shall have a minimum of R-2.1 oK-m2/W (R-12 oF-ft2-hr/Btu). An exterior insulation blanket may be used to satisfy this requirement

Comments:
This criteria is evaluated during the system certification review.

The installer must install the tank that is listed in the the manufacturer's SRCC approved installation manual.

Replacement tanks must meet this requirement as well. In the event the tank is replaced, the installer must ensure that the R-value of the replacement tank meets this requirement. (As well as the gallon capacity.)

In the event the tank does not meet the above stated R-value requirements, the use of an insulation blanket to bring the R-value up to the stated requirement is acceptable.

When installing an insulation blanket, the installer must make sure that access to the thermostat and heating element covers, listing label, etc., are maintained. Figure 1 below shows an insulation blanket retrofit that did not include access to the thermostat and heating element. This should be avoided for safety and maintenance purposes.

Figure 1

In the photograph in Figure 2, the installer has made a cut-out in the insulation blanket for access to the thermostat, heating element, and reset switch.

Figure 2

Since heat loss can occur through the top of the tank as well, the tank in Figure 3 should have been thoroughly insulated.

Figure 3

In the case in Figure 4, the installer had plenty of insulation but little in the way of aesthetics!

Figure 4

Some installers may go too far in their zeal to insulate system components. Figure 5 shows that that installer not only forgot to include access to the thermostats, but also included the system pump and several other components under the insulation blanket! This must be avoided.

Figure 5

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