Domestic hot water from a boiler

Jay_35

Just wanted to say thank you for the suggestion. I will first try the mixing valve and go from there.
Best,
Jay

Jay_35

Domestic hot water from a boiler

Hello. My wife and I are hoping that someone here can help us determine the cause of our fluctuating temperature of hot water.
We do have a winter summer hook up and when we first turn on the hot water it is really hot, we don't have a mixing valve on it, but then it gets, for the most part, cold but it will warm up again.
I have replaced the aquastat and the problem persisted so I then put di-electric gel on the sensor but still the problem persists. I did put in a bottle of Hercules Boiler Liquid prior to all this but it clearly states that "will not clog or coat submerged hot water heating coils,controls, vents or valves". I did drain the boiler after adding this stuff and it seemed to help but I don't know that for sure and really I don't know for sure if the problem existed before that because we didn't have a tub then as we do now and we don't have a problem showering. I did check the flow out of the tub faucet and it is about 2 or 2 1/2 gallons per minute.
Also, sometimes I can hear the burner (oil fired) kick on and then quickly off maybe in about 10 seconds and I don't think the it heated the water form 160 to 180 that fast! Strange. Anybody think they know what is going on here?
Thank you!
Jay

Cosmo_3

suggestions

One is to install a thermostatic mixing valve. That will even out the fluctuations a little.

Even better would be to have an indirect water heater installed. You won't be sorry!

Cosmo

Dave_4

ok ok ok

this is my suggestion to many a home owner that has heating or hot water problems. get the yellow pages and look up a local heating professional. call and tell them you have a problem; explain the problem. let them send a professional to your home to fix it. easy as pie. no more problems. it sounds like you have a few problems going on here. one is short cycling of the burner. second, is fluxuation of the domestic water temperature. third you put something into your boiler and you dont know the ramifications of what you have done. scarey stuff. it sounds like an anti-scald mixing valve will solve the fluxuations in your domestic water, the shower will not fluxuate if it has a single shower valve. these valves are usually set so that they will not exceed a certain temperature no matter what. the are temperature/pressure balancing valves. as for the short cycling of the burner, there could be many different causes for this type of problem... just call a professional. your family will thank you for it.

joann_3

mixing valve

although i always have heat, i no longer have any hot water in my bath tub faucet, only some in my kitchen sink facute, for maybe 3 minutes, then it gets warm. i think it might be the mixing valve?? either way, one estimate i did get, was, over $600, not including labor. do you think this is too much? thank you for any help. joann

chris_86

Sounds like your tankless,...

you have a tankless coil that is cloged up and needs to be replaced? Or the mixing valve on your tankless needs its innards to be replaced, Sounds like classic old tankless coil problems 5-10 years old. If it has lasted longer than that you are doing well. An indierect is a good soulution too many get a new coil thinking they will save because an indirect is more expensive, but 5 years later the coil craoks again...

Joe@buderus_2

Buderus does not offer a tankless coil boiler, but from previous experience a suggestion. There may be a "tempering" valve on the hot water outlet pipe that is "thermostatic" and will mix cold water with the hot coil water. This tempering valve may be failing. Having a pro look at this issue is very important. A tankless boiler usually maintains a temperature of 160 to 180 degrees. If the tempering valve is failing, it may fail and someone may experience serious burn from the 160 to 180 degree water, IF YOU HAVE YOUNG CHILDREN PLEASE CONTACT A PRO ASAP. Perhaps contacting a smaller company or individual may evaluate and fix the problem at a lower cost. Please let us know this works out.