Path: utzoo!attcan!uunet!ncrlnk!ncrcae!hubcap!gatech!cwjcc!tut.cis.ohio-state.edu!osu-cis!att!ihlpl!knudsen
From: knudsen@ihlpl.ATT.COM (Knudsen)
Newsgroups: sci.electronics
Subject: Re: Finding an electrically-controlled valve?
Summary: Need pulsation chamber!
Message-ID: <8514@ihlpl.ATT.COM>
Date: 18 Jan 89 18:48:01 GMT
References: <1404@accelerator.eng.ohio-state.edu> <2925@kitty.UUCP> <2936@kitty.UUCP>
Organization: AT&T Bell Laboratories - Naperville, Illinois
Lines: 15

In article <2936@kitty.UUCP>, larry@kitty.UUCP (Larry Lippman) writes:
> The key to effective
> control in this arrangement is to have a mixing chamber (can be just a coiled
> length of tubing) to mix the hot and cold water BEFORE the output temperature
> is measured.

You also should equip  air chambers (like on old steam fire engines)
to filter out the puslations on both sides of the pulsed valves.
Otherwise the water ahmmer effects may be terrific.
If you hit the resonant frequency of your house plumbing,
your sump pump better be in good shape.
-- 
Mike Knudsen  Bell Labs(AT&T)   att!ihlpl!knudsen
"Lawyers are like nuclear bombs and PClones.  Nobody likes them,
but the other guy's got one, so I better get one too."