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hot water pressure issues with tankless coil-HELP


This is my first post. First off I'm a non-plumbing literate homeowner on a very,,,very tight budget, I have a Dunkirk empire II boiler w/ tankless coil. Water gets very hot but pressure has dwindled to barely a trickle. Had someone install two clean-out valves and acid flush it a year ago. I live in a very remote area currently under about two feet of snow. Cant get anyone out, cant buy the acid (not a liscenced plumber). Is there any suggestions to temp fix the pressure problem? Can the coil be cleaned by removing it? can it be removed without sweating feed lines off of the intake and output? Could really use some advice.



  • RobbieDoRobbieDo Posts: 131Member
    Hard Water?

    I'm assuming that you have hard water, no softener? I have used cleaning solutions to clean the coils but never "acid". I use different stuff than that. How is the pressure on the cod water side, I'm assuming good? Do you have a transfer pump? Sorry for all of the questions.
  • davidcdavidc Posts: 5Member
    need hot water help

    Thanks for the response. Yes hard water, no softner, no transfer pump. Cold water pressure is strong. Cant figure a way to get coil assembly out without mass destruction of pipes!!!! Ant ideas for quick fix?

  • RobbieDoRobbieDo Posts: 131Member
    Clean out valves

    Do the valves that you say are, clean outs, have garden hose connections on them? I would suggest installing a good filter pre the coil, I know this does not help the hard water issues but will help with debris and other particles the filter will catch.
  • davidcdavidc Posts: 5Member
    hot water problems

    yes the valves look just like garden hose valves outside.Is there any way to get the pressure back without taking coil out?
  • RobbieDoRobbieDo Posts: 131Member
    Cleaning solution

    I use a cleaning solution that I get from my supplier, I use a transfer pump. The best thing to do is install a indirect with a softener. I know times are tight but you will need to find a transfer pump and get cleaning solution if you can't buy acid. A filter before the coil will help though.
  • davidcdavidc Posts: 5Member
    transfer pump

    Hey thanks. Where can i buy a transfer pump? and are they expensive?
  • RobbieDoRobbieDo Posts: 131Member
    Transfer Pump

    They cost about $50 to $80, have to put solution in a 5gal bucket, run the solution through until it starts to run at normal speed, this could take awhile.
  • Charlie from wmassCharlie from wmass Posts: 3,974Member
    Some people have luck

    With turning up the boiler temp to above 215 degrees and turning off the water supply to the coil. You then attach a hose to the outlet of the coil. Then you VERY CAREFULLY open the drain on the outlet. as the pressure drops in the coil the water will start to turn to steam. When the steaming stops you start to slowly add more water. You use the steam to clear the blockage. I have had this work once. I have tried it dozens of times to no avail. In your situation it is worth a try and you are not paying me by the hour so you can be more patient. 
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • davidcdavidc Posts: 5Member
    How do you turn up boiler temp

    hey charles thanks for the tip. Not sure on how to turn up boiler temp. There is no mixing valve and hot water gets very hot. I guess i'll try to get it to produce steam. Is there a control for boiler temp settings?


  • billtwocasebilltwocase Posts: 2,385Member
    it may be

    blockage in a flow restrictor, mixing valve, or a stop & waste valve. It could be a rubber washer that is lodged somewhere, or anything. I would have someone who knows what they are doing, or you might get scalded trying to save a buck.
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