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tankless gas water heater question
Most tankless gas water heaters require 140,000 up to 199,000 BTU on residential models. In a lot of homes the gas line is 3/4". I believe on most jobs when totaling up all BTU needed to run all gas appliances the 3/4" line will not be big enough so if the home owner wants to have a tankless gas water heater installed they need to up grade the gas line and that is a major expense when trying to sell TGWH. Does any tankless gas water heater manufacturer have the capability of making the TGWH have priority over the gas furnace or gas boiler. When the TGWH turns on the power from the thermostat to the gas furnace or boiler would be turned off this way the original gas line in the house would be big enough to supply the TGWH and you the contractor would not have to up grade the gas line to a larger size