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Hot water advice/options/questions.

Hi. I live in a Cape style house, with 2 baths, one on the main level, one upstairs. It's heated with forced hot water, with an oil fired boiler. It is impossible to get a decent shower in either bathroom (never mind fill a hot bath). When I use the shower, it goes from HOT for a few minutes, to cold for a few, then lukewarm for a few. I think the previous owner had a separate hot water because I found a circuit breaker labeled "water heater" which is switched off. There is NO hot water heater in the house. It seems to me that my boiler cannot keep up with the demand for hot water.
We have been considering a few different options, and I was looking for opinions, pros and cons, etc.
1: The oil/heating company said they could add some kind of storage tank (and another heating zone for the basement) for about $1600.
2: Installing an electric hot water heater (the electric company also rents these for ~$15 a month).
3: A tankless water heater.
Any advice or opinions would be helpful, and appreciated.

Rodney H
Re: Hot water advice/options/questions.

Yes, it definitely sounds like there was a separate water heater originally. When you stated there was a breaker labeled "Water Heater", that was the clue.

Those new wall mount, tankless water heaters are very good, heating water only when you need it. If I ever need a new water heater, that is the kind I will buy, even if they are a bit more spendy than the upright type, even the big Marathon heaters, with all that super insulation. If you buy the tankless type, be sure you get one large enough for your needs. Your local contractor, or store, will have a chart to show usage levels. One thing nice about them, is that you are not constantly heating water, when you are not using any hot water, like the round uprights do.

I have seen many new homes with the new tankless heaters.

Good luck.

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Rodney H
Re: Hot water advice/options/questions.

I forgot to mention that the tankless water heaters come in either gas, or electric.

Have a great day.

Re: Hot water advice/options/questions.

I would strongly recommend you take the #1 option you mentioned and have the "storage tank" installed, and perhaps the extra zone for the basement,if desired.

The "storage tank" is referred to as an "indirect hot water heater", usually 40 gallons (sometimes 30 gal. for a small family).

The IHWH uses no gas or oil or flue of its own, it pumps the boiler hot water thru an OUTER TANK to heat an INNER TANK of 30-40 gal. of hot water, which is used for domestic HW needs like showers and dishwashing, etc.

You'll never run out of hot water and the operating cost will be almost negligible, since the boiler water is used as the heat medium.

These "indirect tanks" are so widely used by anyone that has a hot water boiler, that they are considered "companions" to the boiler; they last for decades without any problems; this is one of the great benefits of having a boiler and forced hot water heat.

The offer of your oil/dealer of $1600 for the tank and a basement zone sounds like a good deal.

Most people install a Triangle Tube Phase III, but there are many other brands.

I would strongly advise AGAINST the other suggestions, since they require adding a whole new system or a flue for gas or oil-fired heaters, which is unnecessary in your case, would cost much more, and would incur much higher ongoing operating costs.

Re: Hot water advice/options/questions.

Thank you for the responses. I can't do anything at the moment unfortunately, due to lack of funds. Maybe after I get my tax refund.
Are there any "tricks" I could try in the meantime, maybe to get a hot bath?
Should the heat have any affect on the hot water for showers and baths? Would the hot water use the same circulator pumps as the heat? Just curious.

Re: Hot water advice/options/questions.


I would agree with the previous comments by dodsworth.

The type of system you have for the domestic hot water supply (for showers, dishwashing, etc.) is a heater coil located inside the boiler.

This is a wound-up 15' copper coil immersed in the boiler water that holds only a gallon or two of water---one end is connected to the fresh water supply, the other end feeds the domestic hot water lines to the sinks, hot side of the shower, etc.---so once the shower is turned on the hot water will be gone in a few minutes & you get a cold shower---at that point the boiler comes on again to heat the now-cold water in the coil, which will take 15 minutes or so, and another gallon or two of hot water is again available.

Clearly, this is an inadequate system, but can easily be modified if a 30 gal or 40 gal double tank (tank inside a tank) is placed besides the boiler---the hot boiler water is pumped thru the outer portion of the tank to heat the 40 gal. of domestic water in the inner tank (heat exchanger) (via the same pump used for the rest of the system) and thus, there is always 30-40 gallons of hot water available for showers, dishwashers & clothes washers---the hot water in the inner tank never touches the hot boiler water in the outer tank, so it is potable.

You'll never run out of hot water, and since the inner tank water is heated by the same boiler water that heats the house, there is considerable savings with this system over any other available.

I would recommend you have this system installed as soon as you can afford it; the plumber's offer of $1600 sounds very reasonable---these indirects last for decades without trouble or breakdown & are highly insulated to keep the water hot for a very long time.

In addition to Triangle Tube Phase 3, I would recommend also HTP Superstor, Weil-McLain Gold, Lochinvar Squire, TFI Everhot, or even an Amtrol Boiler Mate (Amtrol has a coil design, but is still good & often less expensive).

The Triangle Tube & similar stainless steel models cost approx $1200-$1500 plus parts & labor; the Amtrol costs approx. $700 plus parts & labor.

In the meantime, the only way I can think of to get a hot bath is to heat a large pot of water on the stove & combine THAT with what you can get from the heater coil inside the boiler when turning the hot tap on for 2-3 minutes; OR you might be able to draw only hot water for 2-3 minutes into the tub, wait 5-10 minutes, then draw another gallon or 2 of hot water for 2-3 minutes from the hot tap, then mix with enough cold water to get enough bath water at the right temp.


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