Our house has an EverHot tankless hot water system that feeds off our oil-fired boiler (we have forced hot water baseboards). It looks like an older type of hot water system to me, but maybe not. The water at the taps does not get very hot, or if it does, it does not stay hot for very long. This morning when I got up there was no hot water at all for my shower (I was the first one up). After turning up the heat for a few minutes (which itself took a bit time) I was finally able to coax some hot water from the bathroom sink.

Any thoughts? I have the mixing valve turned all the way in the "warmer" direction. It seems unfortunate that I would have to run the heat just to get some hot water.

(PS - we are new home owners and I have never dealt with this kind of system before. Sorry if this is a simple question)

I am a Florida plumber. Heating and hot water boiler questions are out of my area of expertise.
Having said that I would install a 40 gallon water heater to the system. Good luck, Tom

When we bought our house (25 years ago), we had a "tankless" running off an oil-fired steam system. When we upgraded the furnace several years later, we replaced it with an 80 gallon booster tank that runs off the furnace. As I remember, the "tankless" had a five gallon holding tank and produced lots of hot water, but was not very energy efficient. If you are not getting hot water from your system, especially in the winter, it seems likely to me that the heat exchanger has a problem - perhaps it is clogged. Are you in a hard water area?

We've been very happy with the booster tank. It is true that the furnace has to run to heat water in the summer, but the rest of the year there is hot water galore and no worry about a heated tank.

Thanks for the help, folks. We had the oil company come take a look. They replaced the mixing valve and things seem better now.