Lochinvar MFH-I&S-02 service manual Gas Connections, Being Certain It Is Filled With Water

MFH-I&S-02

If this water heater is installed in a closed water supply system, such as the one		WARNING
having a back-flow preventer in the cold water supply, provisions shall be made
to control thermal expansion. DO NOT operate this water heater in a closed		NOTE: Some models may already be equipped or supplied with a
		combination temperature and pressure relief valve. Verify that the
system without provisions for controlling thermal expansion. Your water supplier
		combination temperature and pressure relief valve complies with local
or local plumbing inspector should be contacted on how to control this situation.
		codes. If the combination temperature and pressure relief valve does
After installation of the water lines, open the main water supply valve and fill		not comply with local codes, replace it with one that does. Follow the
		installation instructions above on this page.
the water heater. While the water heater is filling, open several hot water
faucets to allow air to escape from the water system. When a steady stream		Install a discharge line so that water discharged from the combination
of water flows through the faucets, close them and check all water connections		temperature and pressure relief valve will exit within six (6) inches
for possible leaks. NEVER OPERATE THE WATER HEATER WITHOUT FIRST		(15.2 cm) above, or any distance below the structural floor and cannot
BEING CERTAIN IT IS FILLED WITH WATER.		contact any live electrical part. The discharge line is to be installed to
		allow for complete drainage of both the combination temperature and
		pressure relief valve and the discharge line. The discharge opening
	WARNING
		must not be subjected to blockage or freezing. DO NOT thread, plug
Hydrogen gas can be produced in an operating water heater that
		or cap the discharge line. It is recommended that a minimum clearance
has not had water drawn from the tank for a long period of time
		of four (4) inches (10.2 cm) be provided on the side of the water
(generally two weeks or more). Hydrogen gas is extremely flammable.
		heater for servicing and maintenance of the combination temperature
To prevent the possibility of injury under these conditions, we
		and pressure relief valve.
recommend the hot water faucet to be open for several minutes at the
kitchen sink before you use any electrical appliance which is connected		Do not place a valve between the combination temperature and pressure
to the hot water system. If hydrogen is present, there will be an		relief valve and the tank.
unsual sound such as air escaping through the pipes as hot water
begins to flow. Do not smoke or have open flame near the faucet at
the time it is open.
This water heater can deliver scalding temperature water at any faucet in the
system. Be careful whenever using hot water to avoid scalding injury. Certain
appliances such as dishwashers and automatic clothes washers may require
increased temperature water. By setting the thermostat on this water heater to
obtain the increased temperature water required by these appliances, you may
create the potential for scald injury. To protect against injury, you should install
an anti-scald tempering valve in the water system. This valve will reduce point
of discharge temperature by mixing cold and hot water in branch supply lines.
Such valves are available from the local plumbing supplier. Please consult with
a plumbing professional.

WARNING

For protection against excessive temperatures and pressure, install temperature and pressure protective equipment required by local codes, but not less than a combination temperature and pressure relief valve certified by a nationally recognized testing laboratory that maintains periodic inspection of production of listed equipment or materials as meeting the requirements of the Standard for Relief Valves and Automatic Gas Shutoff Devices for Hot Water Supply Systems, ANSI Z21.22 or the Standard CAN1-4.4. Temperature and Pressure and the Standard CAN1- 4.4, Temperature, Pressure, Temperature and Pressure Relief Valves and Vacuum Relief Valves. The combination temperature and pressure relief valve shall be marked with a maximum set pressure not to exceed the maximum working pressure of the water heater. The combination temperature and pressure relief valve shall also have an hourly rated temperature steam BTU discharge capacity not less than the hourly rating of the water heater.

Install the combination temperature and pressure relief valve into the opening provided and marked for this purpose on the water heater.

GAS CONNECTIONS

The gas supply lines must meet all requirements of the National Fuel Gas Code ANSI Z223.1-(Latest Edition) and/or in Canada CAN/CGA B149 Installation Codes - (Latest Editions).

The minimum permissible gas supply pressure for the purpose of input adjustment is 1.0" water column (.25kPa) above the operating manifold pressure. See the rating plate and combination gas control for the manifold pressure and gas type. The maximum permissible gas supply pressure is 14.0" water column (3.5kPa) for natural gas and liquefied petroleum gases/propane gas.

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