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G

gemma_p

Can anyone explain how they work in simple terms I'm so confused about them

What is port a
What is port b
Is port ab the inlet

Thanks

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Thanks

So water to b goes to cylinder and a goes away when I ask at work people say I confuse them

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Hot water from boiler goes into AB, and then it either goes to A (heating), or B (to heat the hot water) or both (for hot water and heating).
A ball in the valve can move left, right or sit in the middle. Thereby closing port A, closing port B or in the middle, leaving both A and B open.
 
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The default/de-energised position is on HW, but they will seize up in any position.
 
About a year ago I did a write-up of the "Y" plan with a lot of detail regarding the operation of the 3-way valve. It may help some students (it may also confuse others!!) but I haven't had it scrutinised for errors or possible misconceptions. It includes fault-finding but is too long to paste, so can email to anyone who would like a copy as I would appreciate feed-back. You can ask me directly on [email protected]
 

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