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steam heat & hot water question

sara d.
sara d. Member Posts: 3
Hi, I'm hoping someone can help me before I throw money at a plumber (and sorry if this isn't the right place to post but thought I'd try).

I recently bought an old house with steam heat. The boiler is a tankless system. When I take a shower, the water is hot for a while then goes lukewarm after about 4 minutes. If I stick it out, the water goes hot again after a couple of minutes. HOWEVER, If I turn the heat on before I shower, then the water remains constantly hot. Any idea what this means?



  • Steamhead (in transit)
    Steamhead (in transit) Member Posts: 6,688
    Sara, when you have a tankless coil

    the boiler must maintain temperature all the time to keep the coil hot. The temperature control on the boiler may not be set correctly.

    But the larger issue here is efficiency. It costs a bunch to keep that boiler hot all year, due to the "standby loss"- heat going up the chimney when the burner is off. With fuel costs rising, this cannot be ignored.

    If that were my house, I'd switch to a booster tank (stores water heated by the existing tankless coil) or an indirect heater (tank with heat exchanger thru which hot boiler water is pumped). Either solution would be much more efficient than your present system, since these tanks are usually very well insulated and do not have flues running thru them. If no one is using hot water, the boiler would only have to run maybe once a day, or even less often.

    Try the Find a Professional page of this site to locate someone who can make this happen. A good steam pro can also look over the steam system and come up with ways to make it more efficient too. If you're in the Baltimore area, contact me.

    To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"
  • sara d.
    sara d. Member Posts: 3
    thanks for the info

    even though, now I'm scared! can you give me a ballpark of what it would cost to make either of the 2 changes you recommend? and no, i'm not in Baltimore, in NH where there seem to be some pros listed on the Find a Professional page.
  • Where in NH?

    I know some contractors there...

  • sara d.
    sara d. Member Posts: 3
    Noel...the same one who installed this system?

    I think you were at my house this winter! We're in Newbury. My husband met you on this board and you got him all fired up (ha ha) about steam heat. But not enough to make him do anything about the hot water issue...
  • I need to stop asking that question...

    I'll be in your area next all week (going to the fair), I'll get in touch with you sometime after Saturday morning.

    I think the thermostat on your mixing valve needs to be changed, if I recall from my last visit.

This discussion has been closed.