Installation & Operation Manual
4 Domestic side (tank) piping (continued)
NOTICE Verify that the combination temperature and pressure relief valve complies with local codes. If the combination temperature and pressure relief valve does not comply with local codes, replace it with one that does. Follow the installation instructions in this section.
Do not place a valve between the combination T&P relief valve and the tank.
Determine T&P relief valve size by the following specifications, unless they conflict with local codes:
-SIT030/040/050 - 3/4" NPT with a minimum CSA Rating of 105,000 Btu/hr.
-SIT065/080/119 - 3/4" NPT with a minimum CSA Rating of 200,000 Btu/hr.
Standard installation
•Install the T&P relief valve in the connection marked “Relief Valve”.
T&P relief valve discharge piping
T&P relief valve discharge piping MUST be:
-made of material serviceable for a temperature of 250°F or greater.
-directed so that hot water flows away from all persons.
-directed to a suitable place for disposal.
-installed so as to allow complete draining of the T&P relief valve and discharge line.
-terminated within 6" of the floor.
T&P relief valve discharge piping MUST NOT be:
-excessively long. Using more than two (2) elbows or 15 feet of piping can reduce discharge capacity.
-directly connected to a drain. Refer to local codes.
-subject to freezing.
NOTICE | The Lochinvar SIT series water heaters |
will absorb/store less than 200,000 Btu/ | |
| hr when domestic water outlet |
| temperature is 210°F and boiler water |
| supply temperature is 240°F. Listed |
| outputs are based on ASME Section VIII |
| Interpretation |
Do not install any valve between the T&P WARNING relief valve and the tank connection or
on the T&P relief valve discharge piping. Improper placement and piping of T&P relief valve can cause severe personal injury, death or substantial property damage.
with local codes for applicability. |
| Table 4A |
Minimum Relief Valve (CSA Rating) |
| Model | Btu/hr |
| SIT030 | 105,000 |
|
|
| SIT040 | 105,000 |
CAUTION
The T&P relief valve is not intended for constant duty, such as relief of pressure due to repeated normal system expansion. Correct this condition by installing a properly sized expansion tank in a domestic water system. Refer to the expansion tank manufacturer’s installation instructions for proper sizing.
SIT050 | 105,000 |
SIT065 | 200,000 |
|
|
SIT080 | 200,000 |
|
|
SIT119 | 200,000 |
Failure to install and maintain a new, listed WARNING 3/4" X 3/4" T&P relief valve will release
the manufacturer from any claim which might result from excessive temperature and pressures.
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