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Burnham Rev4 luke warm hot water

bocciman Member Posts: 2
I have a Burnham RV4NSL - L2 installed 9 years ago. I have a 1900 sq ft ranch. I have 2 radiant heat zones, 1 small base board zone and a 40 gal Pure Pro Hot water storage tank. The hot water has never been consistently reliable. I could never fill the bath tub more than 1/3 to 1/2 full with hot water. Lately the hot water and heat seem to be lagging. Yesterday my wife took a shower and 40 minutes later I took one and had Luke warm water for 10 mins. It never got hot. Very frustrating!

Any help would be greatly appreciated. Let me know if you need any other info.


  • icesailor
    icesailor Member Posts: 7,265
    Lack of hot water:

    It sounds to me like you have a wiring and control issue.

    If you have always had problems getting enough hot water out of the indirect storage tank, you probably don't have a hot water extender valve or a thermostatic mixer.

    Raising the temperature in a water storage tank is the same as theoretically, the same as having a larger tank. But you must use a mixer for safety and to extend the hot water available.

    There can be other issues. Such as hot/cold cross connections and broken shower valves. If you have hot water in a bathroom sink but it isn't as hot in a shower, you may have a broken valve part of a stuck balancing spool.

    What kind of shower valve, single lever?

    I'd start with the wiring/control first.
  • bocciman
    bocciman Member Posts: 2
    Wiring Problem

    Thanks icesailor for replying. I think you might be right on the wiring issue. I'm a HO and helped build the system with my plumber 9 years ago. At the time we only had the 2 zones of under floor radiant. ( He said I didn't need a mixing valve because the rev 4 had an internal one.) Since then I've added a small baseboard zone for my wife's office in the basement. And also added a 40 gal Pure Pro hot water storage tank with the circ valve on the top of the tank. My aqua stat is installed at the end of my zones. It's set at 155 degrees. Unfortunately my boiler thermometer and pressure gauge stopped working a long time ago. The thermometer in the pipe where the circ valves are reads 120 degrees after the boiler heats up to temp. When it calls for heat that temp drops to 85 degrees then heats up again. I can't tell what the internal boiler temp is due to the thermometer being broke.

    I read a post on a rev 4 boiler that had similar symptoms as mine. It said its possibly a bad board that's only telling the burner the give partial flame. I'm sure I need to have a Burnham / Boiler specialist look at my system due to my abnormal set up.
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