(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 12 of 12

Thread: Hot Water Heat in Tall House

Hybrid View

  1. #1
    DIY Junior Member Joe Steam's Avatar
    Join Date
    Nov 2010
    Location
    NYC
    Posts
    8

    Default Hot Water Heat in Tall House

    I have a four story house with the hot water boiler in the basement. I figure it is about 50' from the boiler to the top radiator. It is a new boiler and I am afraid the contractor who installed it does not know too much about pressure settings.

    Now, someone that knows more than me please correct my assumptions or give me advice:
    Have heard I should have about 5 psig on the top radiator, so this gives me a setting of about 27 psi at the boiler. Although the boiler is rated at a higher pressure, it has a 30 psig relief valve. I am scared to set the boiler so close to the relief.

    Double checking the boiler rated water pressure, should I change the relief valve and operate the boiler at the higher pressure? And then fill the diaphragm tank (empty) with air at my operating pressure?

    I noticed this because the top floors are chilly!!

  2. #2
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,390

    Default

    I don't think it is a pressure issue, and (I'm not absolutely sure), I don't think you'll need that much pressure. The pressure is to ensure in the boiler you maintain enough pressure to keep it from flashing to steam. The water outlet won't (or shouldn't) be hot enough where a small pressure difference could allow that to happen outside of the boiler. It could easily be air in the system or head for the pump that is insufficient to get it to flow there. You may also need to adjust the balance of the zones to obtain the desired flow.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  3. #3
    In the Trades Tom Sawyer's Avatar
    Join Date
    Nov 2010
    Location
    Maine
    Posts
    2,938

    Default

    15 lbs pressure ( factory setting ) is more than enough pressure for 5 stories. If it's not heating then you have other issues like a circulator that is too small. Piping that is too small or some other restrictions in the loop.

  4. #4
    Plumbing Contractor for 49 years johnjh2o1's Avatar
    Join Date
    Aug 2009
    Location
    South*East
    Posts
    1,121

    Default

    You do not need 5 psig at the top of the system. All you need is enough to be able to vent the air from the system. Also in most four story homes it wouldn't be 50 ft. to the top of the highest radiator. You need .43 psig to raise a water column 1 ft.

    John

  5. #5
    DIY Junior Member Joe Steam's Avatar
    Join Date
    Nov 2010
    Location
    NYC
    Posts
    8

    Default Column of Water

    This is an old house with high ceilings, and it is about 50 feet or at least 45. So the pressure of water at 50 feet is a bit more than 21 psig. It is interesting because the boiler installer used a standard water PRV for boiler fill, set at 12 psig. When I bled the upper radiators, I lost pressure up there so nothing came out. So I re-adjusted the PRV to a higher setting. Hence my questions.....

  6. #6
    Plumber jimbo's Avatar
    Join Date
    Aug 2004
    Location
    San Diego
    Posts
    9,001

    Default

    Is this steam heat or circulated hot water?

  7. #7
    DIY Junior Member Joe Steam's Avatar
    Join Date
    Nov 2010
    Location
    NYC
    Posts
    8

    Default

    As mentioned, hot water boiler

Similar Threads

  1. 2 pumps in one well ??? Heat Pump and House
    By dancour in forum Pumps and Tanks Well Forum & Blog
    Replies: 12
    Last Post: 08-27-2010, 06:19 AM
  2. Replies: 21
    Last Post: 01-03-2010, 01:15 PM
  3. Geothermal Heat - Old house is it worth it?
    By shluffer in forum HVAC Heating & Cooling
    Replies: 1
    Last Post: 09-23-2008, 05:40 PM
  4. Heat tape required for house?
    By pauljferraro in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 1
    Last Post: 10-16-2007, 03:44 PM
  5. Sewer cleanout outside house is 8 inches too tall
    By bingo in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 6
    Last Post: 06-09-2007, 01:49 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •