Results 1 to 8 of 8
  1. #1
    Join Date
    Aug 2002


    had a call tonight boiler making loud gurgle noises crackling.
    figured ok air in the system will go out hook hose up hit fast fill open valve to hose and run air out of system, any way it has two zones.
    lot of valves good to blow everything out seperat.
    ok I blew out boiler then zone one then zone two
    now start it up after spending good hour getting air out of system.
    fires up same thing after not even like 2 minutes maybe 3 it starts gurgeling and crackling in the boiler loud check aquastat set at 180f go around touch all the baseboard its hot go back to boiler still making all these wierd sounds now once the aquastat reaches set temp flame goes out sounds stop, only thing going is pump real low.
    but everytime it fires up makes loud sounds.
    I blew zones out again and boiler same thing, could not find a cure for the problem what em I missing.
    oh I also watched the city water meter between filling it and running it meter did not move to indicate a leak.
    house is on slab and lines to baseboard run under concrete
    boiler is a Utica model 75/G AND IT IS 75,000 BTU INPUT & 63,000 BTU OUTPUT ITS A 1983 but real clean looking unit.
    anyone ever run accross something like this

  2. #2
    sounds like (sediment) spelling? may need to try and flush it.

  3. #3
    Join Date
    Sep 2002
    It sounds more like a flow problem to me.If you are getting good flow when you force feed thru the boiler and the zones then I doubt the boiler is sludgeup.

    What color was the water did you have at first?
    How many circ?
    Black iron distribution system or copper?

    Any zones valves? Any manual valves?

    I only seem this several time in my travels and twice it was sludge from poor water and a leaking distribution system.

    The other time the boiler circulator would not come on with a call for heat.

    Install a new temp/pressure guage on the boiler and see what it does when the banging starts.

    Or, it could be as direct said, sediments.

  4. #4
    Join Date
    Aug 2002


    baseboard copper 3/4 inch the boiler is a 1983 has a back flow preventer before the city water comming to it then a fast fill.
    two honeywell zone valves also to shuff off valves for each zoneon the other side above them two valves is the valve i used to blow system out then past that is another shut off going to boiler then past that is the circulator pump water is going in on that side.
    on other side of boiler going out is aexpansion tank then that side also has a shut off for the exp tank and a shut off for that side of boiler, that side goes to zone valves.

    ok I pulled zone valves open one at a time with emergency switch off to boiler, to blow out each zone with water of to boiler and other side closed to zone not being blown out, did it twice plus boiler and.
    but as soon as this thing fires up like after 2 to 3 minutes it starts making gurgle noise and popping noises then as it gets hotter it gets louder also the gauge on the side of the boiler well there never right 100 percent anyway but it was reading like 170 on temp and on the pressure was bouncing between20 to 22 but maybe that was from it popping and stuff causing it to shake a little.
    boiler itself is cast iron under the thin metal cover it is a 1983 but looks clean

  5. #5
    Join Date
    Aug 2002


    the homeowner did have the bedroom zone re piped going out cause it did break under the concrete before the baseboard 4 years ago, i noticed two 3/4 inch copper pipes comming out of concrete floor and cut off, so i asked them.
    but the living room zone is much larger they did not have a problem with that he said.
    i went in the living room touched a elbow at the end of a baseboard run felt like little air or something going through it besides water.
    ichecked the water meter it was not moving but i think with the pressure in the system and the 180f water it would not show up on water meter for a while if it were small leak no.
    this one is a first for me seeing this i blow out these things at least one a week on heat calls.
    water comming out had little rust but not real bad had it going in hose then in five gallon bucket to see bubles thing is second time blew system out only seen little bit bubles from boiler but zones no air bubbles, well i was going in and out from laundry room to outside to garauge to see water comming out.

  6. #6
    Join Date
    Aug 2002

    direct hvac

    there is no valve below the circulator pump to flush the boiler out only.
    only the one I used was up above the boiler before the circulator pump.
    how would u flush remover circulator I guess right what a mess that would make.

  7. #7
    Join Date
    Aug 2002
    OK I guess they need a plumber with a power flushing machine to power flush the system did little google research thanks for your help i will remember this for the future never seen one do this before thanks agian

  8. #8
    Join Date
    Nov 2001
    lorain county,Ohio
    had this a few times in the past where steam is forming under scale/sediment in boiler. hooked acid pump to and from boiler and pumped mild acid solution thru boiler
    then flushed out. vinegar would probably work fine.

    used vinegar once on a large steam boiler.was used to supply steam to pasta extruding machine.that system used
    lots of potable water.

    what you probably are experiencing is the same thing that happens on h20 tanks.

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