I have a 532/i system and it has dropped below the green into the red which even i know is a bad thing but because of this as you all will know it won't switch on and heat my house.
So how do you use the T bar to pressurize the system?
I have found where the T bar goes and can lock it into place but i can not see how to pressurize it back into the green
i'll assume the t bar you mention is the filling loop key. if so there will be a small plastic knob next to where you lock the key in place, turn that to let the water in.
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