Results 1 to 4 of 4
  1. #1
    Join Date
    Sep 2019
    Posts
    2
    Post Likes

    Any Burnham Revolution Experts? I need some advice.

    I recently purchased a home that was built in 2003, located in Southern New Hampshire, has 3 heat zones, an indirect hot water tank and has 3000 sq. ft. of heated living space. It has an original, propane-fueled Burnham Revolution, Model RV5PSL-12 boiler. I am questioning its fuel consumption as it seems excessive to me and from what I have learned this system may have been installed incorrectly. According to the installation manual I have, the zone circulator pumps should be installed on the send side and they are not. The circulator pumps are on the return side, which is typical for most boilers. There apparently is interference with the internal variable speed mixing circulator having the zone circulators on the return side.

    In speaking with a few service companies I am getting conflicting answers. Some say it makes no difference at all, some say it makes very little difference some say they should be moved per the installation manual and efficiency will improve.

    Before I spend the money to move the curculator pumps I would like to get advice from an expert with these boilers. I reached out to US Boiler (Burnham) but they will not talk technical with a homeowner. I would like to to know if its worth doing given the age of the system . What would the efficiency improvement be in %, if any? Will I get a payback in fuel savings?

    The system runs good however the baseboard radiators do take a long time to heat up, eventually they do, thus the system seems to run a long time when there is a call for heat. This is what led me to investigate this further.

    Thanks in advance for any advice you may have.

  2. #2
    Join Date
    Jul 2013
    Location
    Richmond, VA
    Posts
    4,558
    Post Likes
    Bumping this for visibility, I'll take a stab at it.

    No particular experience with that boiler, but I have to imagine the difference would be almost immeasurable. I can imagine the cost of moving those circulators and can say you probably won't save enough fuel to make up for it. The reason I believe that's the case is because the main purpose of a boiler is to add heat to water and reject that heat into the space. If the boiler is burning fuel properly and heating water, that heat has to be going somewhere or the boiler would just short-cycle because it reaches temperature quickly. It's hard to judge from here what your total radiator capacity is, piping layout, etc. which can affect runtime. Here's some questions:

    What are you paying for fuel? Do you have any other propane appliances in the house? Is there any historical record of fuel consumption you can lean on?

    What do you normally keep your thermostats set at? Do you set them back at different times of the day?

    Has any of your boiler technicians performed a combustion analysis on the boiler? Does the boiler have proper gas pressure at all times?

    Has anyone performed a load calculation on your home and assessed the total radiator capacity?

  3. #3
    Join Date
    Sep 2019
    Posts
    2
    Post Likes
    Thread Starter
    Thank you. Here are some details and answers to some of your questions.

    The house is located in southern New Hampshire, US Climate zone 6, has a main floor of 1825 sq ft finished living space. The lower level is a walk out finished basement with the perimeter walls being concrete half way up and framed the rest of the way up to the 1st floor deck. The finished living space in the basement is 1200 sq. ft and is all studded, insulated and sheet rocked. The remainder of the basement area consists of a 25 x 25 unheated garage at 625 sq ft and a small utility room where the boiler resides. The utility room is insulated. The unheated garage is directly below finished living space. All wall framing in the house is 2x6 and is well insulated in the walls and attic. The are 3 zones, the main living area at 1200 square ft, the area above the garage at 625 sq ft and the finished basement at 1200 sq ft. Windows are of good quality dual pane. The main living area does have vaulted ceilings.

    What caught my attention this past wnter was that the house was not lived in full time so the t-stats were set to 58 most of the time. Maybe 6 days of a given month they were turned up to 65-68 degrees. My full time house in Northern Connecticut has an oil fired system and the heating cost was substantially less. I know it’s not comparing apples to apples but none the less the New Hampshire house seemed excessive to me considering the time-stats were lowered most of the time.

    just prior to purchasing the house last October I had a house inspection done. One observation that the inspector made upon testing the heating system was how long it was taking for each heat zone to get hot. The zones eventiually all did get hot but it did take a while. He observed that the zones were filled with antifreeze that had never been changed or serviced and suggested that maybe the antifreeze had coagulated overtime and is impeding flow. At his suggestion the homeowner agreed to have the system serviced and purged of all the antifreeze and refilled with water. This was done. The efficiency of the boiler was tested at that time and it came in at 87.9%

    Once the heating season began I noticed no improvement in the time it took a zone to get hot, thus my investigation began and I did find the info on the zone circulator pump location for this boiler. The theory is having the zone circulators pushing into the system causes the variable speed internal to not be able to properly mix the boiler water into the zone therefore taking a long time to get up to proper temperature.

    Some data points for propane usage:
    November 2018 - 101.68 gallons, 3700 cu. ft. $203.26 read date 11/27/18
    December 2018 - 109.92 gallons, 4000 cu. ft. $219.73 read date 12/27/18
    January 2019 - 134.65 gallons, 4900 cu.ft. $269.75 read date 1/28/2019
    February 2019 - 112.57 gallons, 4100 cu. ft. $225.23 read date 2/25/2019
    March 2019 - 95.43 gallons, 3400 cu. ft. $186.77 read date 3/25/2019
    April 2019 - 52.31 gallons, 1900 cu. ft. $104.37 read date 4/24/2019
    May 2019 - 24.73 gallons, 900 cu. ft $49.44 read date 5/28/2019
    June 2019 - 5.5 gallons, 200 cu. ft. $10.99 read date 6/18/2019
    July 2019 - 13.74 gallons, 500 cu. ft. $27.47 read date 7/26/2019
    August 2019 0 8.24 gallons, 300 16.47 read date 8/27/2019

    No heat load calculations have been done at this point yet.

  4. #4
    Join Date
    Jan 2012
    Location
    Broomall, PA
    Posts
    2,543
    Post Likes
    I don't think your consumption is that bad.
    The main thing the piping could do, like CircusEnvy alluded to was cause short cycling, burning more fuel.
    Another thing that can waste fuel is any hot water faucet or any domestic hot water line leaking, or lacking heat traps, or uninsulated piping, causing the indirect to call more often than it should. For example, the only thing that should be running in the summer is dhw calls. Why is July so high, compared to June and August?

    Is the return water sensor properly mounted and working correctly?
    Is the control sensing the proper temperature from the sensor?
    Either one of those would cause the boiler circulator to not run at the correct speed.

    Maybe it's something simpler, like a small propane leak outside.
    Or maybe the boiler is just too big. I looked up the specs but didn't see a btu input/output in the specs. But if the '5' stands for 5 section, it's way too big and would also cause short cycling, especially with 3 zones.
    Can you post a picture or a diagram of how it's piped.

    The piping diagram in the manual isn't ideal.
    Generally you'll want to pump away from the expansion tank. Air elimination should be where water is the hottest.
    If you're piping primary-secondary, usually the circulator for the boiler loop pumps into the boiler. Also if you had a boiler with a large pressure drop thru the heat exchanger, then you would want to pump toward the boiler with the proper circulator on the boiler loop. However, this boiler has it's own dedicated circulator pumping into the boiler for proper mixing/boiler protection.
    So I'd have the controls double-checked, and the circulator double checked. Could be gummed up from the antifreeze as well as any important component.

    As far as zones getting hot, that's a different problem. 'Getting hot' & 'staying hot' are 2 different animals. Again, maybe antifreeze gummed up the valves and reduced pipe diameters on the smaller pipes. Or not enough water in the system, or no circulation. Just because the circulator is running doesnt mean it's working.
    If you have a large water content system, and you have proper boiler protection, cold start and deep setbacks will waste energy. Set it where you like it and leave it that way. Maybe a couple degree set back at night if you like it cooler, but expect almost an hour per degree on recovery.

    If I were tackling this problem, I'd spend some time checking the components, making sure it's properly bleed/filled/purged, fire it up and take some temperature readings.
    If it still wasn't working as it should, then it's time to open up the system and start doing the math on the zones-pipe sizes, length, head and circulators.
    Home inspectors usually know very little about hydronics, or hvac at all.
    Uh...Google it yourself!

Posting Permissions

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