2. How to reset pressure on my Heat Interface Unit

How to reset pressure on my Heat Interface Unit (HIU)? 

The Baxi AquaHeat HIUs have an analogue pressure gauge visible on the front of the unit, the optimum system pressure is highlighted with a green triangle on the gauge. If the system pressure has dropped below the optimum amount, the pressure can be topped up using the Baxi EasyFill (where the Baxi first fix rail has been installed). 


The EasyFill can be located on the top of the unit. The below video shows the top-up procedure for one of our Baxi gas boilers with which we utilise the same filling lever.

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