[Robie]

I have a Peerless, oil-fired boiler that supplies both heat and hot water to a 2 bedroom ranch.
Since the boiler has to run to keep hot water for daily use, even when home heating is not required, I have been investigating having a propane-fired Rinnai tankless system installed. I could shut down the boiler during the months when no home heat is needed (probably 8 months out of a year) and just use the Rinnai for daily hot water needs. I was ready to give the go-ahead for this installation until the guy who did the service/maintenance on the boiler came the other day.
He mentioned something I have never heard of...a "Triangle Tube Indirect Fired Water Heater" http://www.triangletube.com/TriangleTubeProduct.aspx?CatID=6&PID=2
He said he uses one with his oil furnace and has seen a 25% reduction in oil use.
What to do? Anyone familiar with these Indirect Fired Water Heaters?
Just looking to save some money in the years ahead and would appreciate any feedback.

 

[beenthere]

Indirects are nice. And can save you on your fuel bill. 25% is questionable. Since it depends on your actual usage.

Probably more then a propane tankless, because propane isn't cheap either.

 

[naptown CR]

Triangle Tube makes a good boiler I am familiar with their gas units.
However the indirect water heater does not preclude you from firing your boiler during the non heating months and costs about 4-6 grand to install.
The more important thing to ask is if your boiler is a cold start meanng it only fires when there is demand for heat or hot water or does it stay hot at the preset temp all year. A cold start will only fire if there is a need for heat or hot water. With the heat in the off position and no one running hot water turn the teermostat up on the boiler if it fires up it is not a cold start. change the control and you will save solme money or install some solar that will save you even more PM me if you want more info and go to
www. dsireusa.org for more info on the solar part.

 

[Robie]

Thanks for the replies. The boiler I have now comes on to maintain water temps. Though he didn't give an actual figure, he said probably around $2000 for the tank installation.
The company installing the Rinnai wants $2300.
I'm just now reading a review of this Triangle Tube heater and it says that it's not meant for single family dwellings...only multi dwelling and commercial. There have been 3 people ask why, but no responses.
One of the reasons this interested me is that years ago, I shut down the furnace (boiler) because of an extended vacation only to come back to a flooded basement. Apparently the gaskets between the cast iron "radiators" cooled and shrunk, causing the leak.
I'm leaning towards the tankless but don't want a flood on my hands either.
Any comments on that part of the equation?

 

[beenthere]

Well, since he said his boiler supplies his hot water. And he is only hearing of an indirect now. Most likely it is not a cold start.

After an indirect is installed. Hos low limit can be set very low, that the boiler seldom fires up except for heat, or indirect regeneration.

Or, if its a low water content, he can ask his contractor to convert it to a cold start, using the existing control, and save money by not buying another control.

 

[beenthere]

Common for the push nipples of a boiler to leak when it gets cold.
Your contractor can set the aquastat to maintain a min temp, so that doesn't happen after the indirect is installed.

Indirects are used commonly on homes with just 2 people. Not sure what section you read that said they aren't good for small families.

 

[naptown CR]

Triangle tube makes a variety of boilers.
I would seriously look into a solar option and change the controls on the existing boiler to create a cold start situation. This will not cost much more at the end of the day with current incentives and will save you in the long run.

 

[tgeb]

I looked into the indirect fired water heaters, and for me at the time, could not justify the cost. (still can't with this economy) :sad:

I ended up getting a new aqua stat that is better suited for a boiler with domestic hot water.

Essentially it allows you to set a lower limit for domestic hot water, and the boiler runs way less when heat is not needed. I have not monitored the usage to be able to tell you how much less oil I use but I do know it has made a difference.

Honeywell 7224

I bought mine here
https://keithspecialty.com/k/67-143.htm

Probably not the best option, but it can save you money in the short run.

 

[ciws14]

"Cold Start"???

Is this boiler even able to condense? It's oil fired right? I don't think allowing the boiler to come on only for DHW would be wise as it would cause your boiler to condensate for which it is not designed. Maintaining a 140 degree boiler loop temp is crucial for equipment protection. If you want to cut energy costs, have your combustion checked with an analyzer along with a good cleaning if you haven't already done so. Around here our #2 fuel oil can vary in blend according to the season, so it is common to have anything oil fired checked out at least twice a year during the season change. Another option is to have the boiler "isolated" from the rest of the system with some electric zoning valves. So if there is no call for heat nor DHW, the valves could isolate the boiler loop and allow it to maintain 140 degrees without heating up a lot of water unnecessarily. Beenthere is on the money, the indirects sized properly will be fine for 2 people and many more. Again, proper installation is critical. Bear in mind that when you go indirect, an outdoor reset is no longer used.

 

[George.hicks]

I would keep it simple if I were you. Buy a 30 or 40 gallon propane hot water heater and turn it down when you are not going to be there. If your hot water usage is low, you might even consider electric and turn the power off to it when not in use. Why spend thousands of dollars on fancy equipment to save a hundred dollars a year?

 

[mrmike]

I would keep it simple if I were you. Buy a 30 or 40 gallon propane hot water heater and turn it down when you are not going to be there. If your hot water usage is low, you might even consider electric and turn the power off to it when not in use. Why spend thousands of dollars on fancy equipment to save a hundred dollars a year?

I totally agree here- how long would it take to recuperate the initial investment? I have the same set-up as you have-& originally I went to an electric on demand - which was really reasonable & I installed it myself- to use in the "non-heating" season. I liked it so much- I now use it year-round............ I know on-demand is a stickler here-- but for me it was the way to go & saved me a lot of money- but like I stated my investment was low............................