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Runtal towel warmer connection

rainy Member Posts: 1
Having read many posts here, I was hoping for some advice on connection my Runtal 4624 towel warmer. It will be the primary heat source (still considering electric radiant for under the tiles) for my bathroom. I'm replacing a roughly equivalent amount of  fin tube with this unit so I think the BTU output should be a fairly close swap after the towels are accounted for.

I want to plumb the unit into the middle of a well-balanced series loop of fin tube baseboard in a bungalow in Victoria BC (very mild climate....perhaps 5-10 days a year below freezing). I'm running a Lochnivar Knight with outdoor reset which typically runs at about 20%.....water temps of 118-123 degrees.

The question is whether I should connect this directly into the series loop like the rest of the baseboard, or will the constriction from 3/4 inch to 1/2 inch be a problem?. Alternatively I could use venturi tees, or use a pair of conventional tees with a bypass and a globe valve in between.

Thanks for the help.


  • Paul Pollets
    Paul Pollets Member Posts: 3,508
    edited July 2014

    Towel warmers, or any wall panel radiator works better if piped with a separate supply and return, rather than in series. If the TBW is at the end of a series run, it may not get warm enough. It also means you can't use a TRV or you'll affect the other heating elements attached in series. The restrictive flow from 3/4" to 1/2" will also have an affect on the connected baseboard.
  • Zman
    Zman Member Posts: 7,330
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein