Usually on the top, on the incoming cold pipe.
It should be right above the tank on the incoming cold pipe.
Connect the domestic coil thru a tempering valve to the hot water pipes in your house and turn off the valves to your old hot water heater. You should include a shutoff valve so you can revert to the hot water heater when you have your coal boiler shut down.
Mixing valve usually for tempering domestic hot water.
It will cost about $60.00 to replace a hot water gasket valve on a boiler. This is if you do it yourself. If you hire a professional, they will charge you for labor and the ending cost will be much more.
There is a shutoff valve on the cold pipe going into the H/W tank, if you close it no water will come out of the tank. There should also be a shutoff valve on the wall below each faucet/tap.
You can't because it is non potable water. That is why there is a Watts 9D check valve on your boiler. You need a heat exchange water tank to do what you want.
A zone valve is actuated by a thermostat and will allow water to pass from the boiler to radiant floor piping or base board radiators or in some cases a hot water storage tank.
No. Hot water directly from boiler is not potable.
The hot water usually goes to a storage tank. The PRV goes there, near or at the top.
new boiler and hot water heater
This depends on whether the hot water comes from a combination boiler or from a hot water tank with a header tank feeding it. For a combination boiler the fault would probably be at the boiler, possibly from scale in the heat exchanger. For the system that uses the header tank and a hot water cylinder it could be that the float valve in the header tank is stuck an there for it is not refilling the tank or debris has entered the tank and is blocking the outlet.
Flow control valve that will over come stratification of hot water flowing through the system until a circulator comes on
is it a diverter valve or immersion heater then? only need a simple answer haha