Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
A vented cylinder replacing an unvented cylinder, I assume this is a no go as mentioned above, a vented cylinder will not be able to withstand the pressure of mains water. Is this correct?If on the other hand, you just mean that a vented cylinder, with the secondary plumbed in conventionally to an open vent and cylinder feed cistern, is to have its primary coil connected to a sealed primary boiler circuit, then there is nothing wrong with that.
Reply to the thread, titled "Using a vented hot water cylinder on an invented system" which is posted in UK Plumbers Forums on Plumbers Forums.
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