Thermo Products MHA1-75N 用户手册

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All installations and services must be performed by qualified service personnel. 
 
22 
Piping from the natural gas meter to the furnace shall be in accordance with 
requirements of the local utility. Piping from the propane tank to the furnace must 
follow the recommendations of the gas supplier. 
 
A readily accessible, design certified manual shut off valve with a non-
displaceable rotor member shall be installed within six feet of the gas equipment 
it serves. A union or flanged connection shall be provided downstream from the 
manual valve to permit removal of controls. A 1/8" N.P.T. plugged tapping is 
provided at the inlet of the gas control for connection of a test gage to check gas 
supply pressure to the furnace. Unions must be of a ground joint type or flanged-
jointed using a gasket resistant to LP gas. Pipe dope or sealant certified to be 
resistant to the action of liquefied petroleum gases shall be used on all threaded 
joints. 
 
Left and Right Gas Supply Piping  -  This furnace is set up to accept either left or 
right side gas piping using a street elbow and a straight pipe. 
 
A sediment trap (drip leg) must be used on both propane and natural gas 
installations, to trap oil, condensate and other impurities, which might otherwise 
lodge in the gas, valve or plug the burner orifice. The sediment trap shall be 
installed as close to the furnace inlet as possible. When there is excessive 
condensation between the gas meter and the furnace, a sediment trap shall be 
provided at the outlet of the gas meter. Failure to install a sediment trap may void 
the limited warranty on the furnace, refer to Fig. 6. 
 
If local codes permit the use of a flexible gas appliance connector, always use a 
new listed connector. Do not use a connector, which has previously served 
another gas appliance.