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Adding Toe Kick Heat to existing zone

Paul_M Member Posts: 11

As a DIYer, I'm considering adding a toe kick heater(TKH) to my hydronic baseboard heating system, and I'm almost ready to proceed. I'm hoping the experts here can help convince me that my approach is sound (or not).

My problem- the previous owner left only 2' of baseboard in the ~220 sf renovated kitchen, which has an exterior door, a garage entrance and 2 skylights. Brrrr!, the thermostat is in the living room on the other loop of the 1st floor heating zone.

System summary- The oil-fired Weil-McLain boiler has a domestic coil, is set for 160-182, and has a single Taco 007-F5 circulator on the return side for both heating zones (1st floor and 2nd floor.) The 1st floor target zone for the TKH has two 3/4" loops, rejoining to a 1" pipe for the final 30' to the boiler. In addition to that 30' shared return, loop 1 is 70' with 30 total feet of finned pipe, loop 2 (my target loop) is 150', also with 30' of finned pipe. (Diagram enclosed)

Approach- I'm leaning toward the Turbonics Toester 10/12 which is rated from 6500 BTU/h at 160deg on low fan, to 10000 BTU/h at 180deg on high fan. The target location is before the midpoint of its loop: ~12' of finned baseboard before and 18' after. I'd like to minimize heat loss for the first 6' of baseboard after the TKH location and which is at the far end of the loop.

Questions- 1) Since I have some flexibility in connection, is it either acceptable/appropriate/advisable to connect the output side of the TKH back into the main loop at point after it passes through that next baseboard section?  This return Tee would be ~40' beyond the input Tee to the TKH and would require adding about 10' of 1/2" pipe. 2) If this approach makes sense, what type Tees are advised (monoflo vs venturi) and should there be one on the input as well as the output side?

Thanks, Paul_M


  • Radix
    Radix Member Posts: 2
    Just a comment..

    I don't have any answers to your questions, but I do wonder if placing a 6500-10000 btu heat source specifically at a spot where people often stand is the best idea...?

    Would it be possible to locate it under a less used cabinet front ? r(ather than at the sink) or use two of a lesser output?
  • Paul_M
    Paul_M Member Posts: 11
    One unit or two

    Thanks Radix, I've also had some concern about that. My alternate space under the peninsula gets even more "standing time" for food prep and cooking than the sink area. As you suggest, I could install 2 smaller units, keeping to those locations for easy access through the wide cabinets. If so, I'd go to the sink first, then directly to the peninsula, then back to the main loop as indicated in the diagram, thus minimizing the amount of 1/2" pipe.

    Others- is there anything wrong with my thinking?
  • Harvey Ramer
    Harvey Ramer Member Posts: 2,239

    I think you would be well advised to split loop 1 and loop 2, on the first floor, into 2 separate zones. The piping configuration that you have works well as a single zone only when the 2 loops are equally balanced. Yours aren't. I would place the 2nd thermostat in a central location of the three rooms on that side. I see no problem with installing the toe kicks at that point but, it is also possible that after you have it zoned, you might not need them.

    Zone it first.

  • Paul_M
    Paul_M Member Posts: 11
    edited September 2014
    New Zone options

    Harvey et al-

    First, I apologize for an error- Loop 2 length is 145', not 180'. So, while it's not quite as imbalanced, converting the loops to zones has some appeal. I probably still need to add BTUs to the kitchen area, because it's currently served by only 2' of baseboard and is over a crawlspace that's colder than the main basement.

    I'm obviously not a professional, so please bear with my questions. If I just convert the existing loops to zones, I'll end up partially heating that large central area via both zones. I don't know if that's a good or bad thing. Another option might be to short-circuit Loop 2 so that it doesn't service the kitchen at all, and add separate zone just for the kitchen/laundry area, still adding a toe-kick on that new zone, probably a smaller 6000-8000 BTU model.

    I was initially hoping for a low cost quick-fix solution with the toe-kick, but now I'm re-thinking. All feedback is appreciated.

  • Eric_32
    Eric_32 Member Posts: 267
    I always pipe in the supply and return for a toekick somewhat together off the "main line" and I never feed another section of heat between them.

    I just use one diverter tee, mono flow or venturi on the return only. Try to keep the lenght of pipe down on the 1/2" feeding the toekick, your better to run the main line closer than have 60' of 1/2" off to a toekick.

    Be careful on the pitch of the line on the toekick. It is going to get bled thru the coin vent on the toekick itself, so no up then back down runs trapping air in the piping. Even if you bleed it good, and there is a pocket in the system that finds it's way into the 1/2" the air will be trapped.

    Do it like the old timers did, anytime I use a monoflow or venturi, I give slight pitch up to the heater so it is the high point and air wont get trapped along the way.
    Bob Bona_4
  • Paul_M
    Paul_M Member Posts: 11
    Eric- I was with you up until "... I give slight pitch up to the heater". Since I'll be tapping the monoflow into an existing 'basically horizontal' run of pipe in the basement, a foot below the heater; how do I give it a pitch?
    Per other forum comments and from a local pro, I'll probably create 2 zones per attached.
  • Bob Bona_4
    Bob Bona_4 Member Posts: 2,083
    Sounds good. Eric is saying just avoid droops inthe piping to the tk and keep the piping level or more up on it's way to the tk to help keep air from getting trapped.
  • icesailor
    icesailor Member Posts: 7,265
    Split the two downstairs series loops into two zones with zone valves. Have one thermostat in the kitchen. If the kitchen is open to a dining room or other room on the same zone, you may not need the Toe Kick heater. I'm particularly fond of the Smith's Environmental units. They make a really excellent floor model if that works for you.
    Don't loose your lunch about the heater blowing hot air on feet. I've installed many a toe kick under kitchen sink cabinets. The gals just rave about having warm feet in the AM. Especially ones with thyroid issues and have a problem regulating body temperatures and always complain about being cold. I've always installed a Monoflow in the main as close to the heater as possible. I've never had a problem.

    If the heat for the kitchen is on the same zone/room as another connected room with a large opening, you may not even need the Toe Kick Heater. Properly installed Toe Kicks can be a PITA to do the total installation correctly. The Smith's Environmental floor heater is like no other. It is a dedicated unit and not a coil that fits in many other applications. It is no POS and is competitively priced.