I am plumbing in a basin for an en-suite and will be fitting a 15mm single check valve on the hot inlet pipe prior to securing to the hot tap. I was told a check valve does the same job as a non-return valve? I thought I could test the check valve is working before installation by simply blowing into it on the inlet end of the valve marked by the arrow. However no air can pass. Does this mean the valve is faulty or that when connected the water pressure will open the valve? Just nervous to fit as once installed access will not really be possible.
Thanks in advance.
Thanks in advance.