Home>Discussions>PLUMBING>Water temperature requirement for hot water baseboard?
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Re: Water temperature requirement for hot water baseboard?

That's good, what von steuben, brewster and the others said---what they said.

For leslie:

Leslie says "why am I so soft in the middle"
"Why am I so damn soft in the middle"-----

My life is soooo hard, I could end up a cartoon---get these mutts away from me.

I can call you leslie, and leslie when you call me, you can call me al------

Re: Water temperature requirement for hot water baseboard?

Just to clear the air. My name is Chris and I have no clue to the Leslie person any of you speak about. Again, I see nothing in anyones arrows other than loyalty that shows any discredit to my post.

Atleat come back with some facts. I would more more than happy to take this matter of whether I speak the truth or as some have said my stupidity to sites where leading heating pros other than myself that are highly versed on the subject gather.

I never attacked Nashua. I simply voiced my opinion based on fact. Which by the way I still haven't seen any support post from anyone based on their opinion of the subject matter.

Since None of You

Could bring anything to the table and to further provide facts to my statements I started my own thread at heating help concerning the subject matter.

Each of you is more than welcome to particiapte via the link below. Hopefully I'll see you there and we can all learn something.


Re: Water temperature requirement for hot water baseboard?


Listen, don't try to ram your low opinions down the throat of the members of this board.

I think that you're just a stooge for the HVAC industry that just wants to sell product at the highest price, whether it works for the homeowner or not.

That's why people like you hate Nashua Tech so much; you know he's honest and is not out to gouge the customer.

Re: Water temperature requirement for hot water baseboard?

Wow, Pelton nailed it!

The HVAC industry has been trying to descredit Nashua since he arrived years ago.

They know he'll save people on this board thousands of dollars in many cases on a boiler purchase.

They periodically send a gnome like hvhehcca/leslie but they never will stop the man.

Molly Pitcher
Re: Water temperature requirement for hot water baseboard?

Just my 2 cents.

I can remember numerous times over the years in past winters when someone without heat & no money to call a service tech would post.

Nashua on numerous occasions intervened and got the boiler up and running to save the house from freeze-up and worse things.

And he'll no doubt be there THIS winter to do it again for some member for just a "thank you".

The HVAC shills like hvhehcca hate that to no end!

Re: Water temperature requirement for hot water baseboard?

Can we please stick to the subject matter. I didn't read anything in my posts that said Nashau has been wrong or provided bad advice in every post he has ever written. I'm sorry if all disagree because of loyalty to him but when he is wrong he is wrong. In this case his position on baseboard output and whether you can heat a home with low water temps is wrong.

I again offer all to please bring facts on the subject and leave loyalty at the table. I'm sure Nashau has helped many in the past and that's a good thing but it also doesn't mean everything he writes is fact.

I'm not welcome because I disagree and provide factual information. I could care less what you put in your homes but I do care that the right information that allows someone to make a proper decision on how and where they want to invest their money gets into their hands. It's not my decision to spend anyones money. My loyalty is not the industry but to providing consumers with proper advice. For more information on who I am please visit www.hvhehcca.org

Re: Your Plumber As Well As Nashua Are Wrong

If you are "not trying to be sarcastic" then it must come naturally to you.

I am in doubt about many of the statements made in your post and I am not here to defend Nashua, I suspect he is quite capable of defending himself. I don't know who "Leslie" is, and don't care.

1. You state "Generally and this is a fact, 95 percent of homes are over-radiated and current equipment oversized." If this is a fact, please document what study found it to be so. I have found just the opposite as far as "over-radiated", in many homes I have worked on.

2. You go on to state "The dew point which in our world generally starts when we can get return water temperatures back to our condensing boiler at 134 degrees." Is this a typo, or are you listing another "fact" which apparently I have never heard of in "my world" ?

3. You talk of rooms with R-19 insulation like it is universal, while most new homes never reach that value without 2" x 6" wall cavities. Add the best windows on the market, and you will still drop the total much lower. Since this is an existing home, I doubt that it even reaches R-14. Since your whole theory is based on this assumption, I have serious doubts about it's validity.

4. You assume that it will be fine to operate the existing convectors at 160*F. maximum temp. without knowing their type or length, as well as the heat losses of the room. You tell the OP that another Technician with a more conservative view is "wrong" and his statements are based on "myth". I have seen many convectors that could not heat a room properly at 160*F. and to make an overall judgement on this system without having any of the necessary information, is not only foolish, but could cause the OP to make a very expensive mistake.

Forums are meant to help people make decisions that in many cases are very costly and permanent. To justify your postion of using a condensing boiler you claim you have installed hundreds without a callback. We have an installer in town with the same record, the systems don't work properly, but he is so rude to the owners that they just live with the problem or call someone else. And response time is very important. If the owner has to wait three hours or more for a room to heat up after raising the stat, he is going to be unhappy. That is a very real possibility with an undersized system.

You need to think about erring on the side of the homeowner in these unknown situations, instead of telling them they will have no problems heating a warehouse with a candle, even though it can be done with enough insulation. That system might also have a "slow response time".

Re: Water temperature requirement for hot water baseboard?


I suggest you read this study which was in another of my posts.


Now concerning my use of R-19. I never said that it was the norm. I also said you do need to do a heat loss and you must measure length of emiiter and calculate output based on the water temp you design for. I even went as far as to say you must also calculate flow rate for the zone.

The difference between R14 and R19 is not substanial in the loss through an outside panel but does need to be calculated.

Ti-To divided by RV = btu loss per sqft

Where as Ti = Temperature Indoor
Where as To = temperature Outdoor
Where as RV = The R-Value of the outside panel whether it be wall, door or window.

I live in a climate that requires 0 degrees so that is what I used. You should always use you climates coldest day. I stated that in my posts. I also did state that you have to calcuate infiltration factor.

I based all my statments based on a heat loss needed to be done. Oops I forgot to add this link for your question concerning dew point.


Re: Water temperature requirement for hot water baseboard?

Thank you for the quick response. I read through the study rather quickly, and will give it more time this evening. I don't doubt that a condensing boiler can be used to save energy on existing systems designed for 180*F. water, although the savings will be somewhat reduced and the payback time will be greater. What I do have a problem with is supplying sufficient heat to keep the room comfortable.

From some parts of the study I found these statements. I may be taking them out of context, and will give them further thought when I have more time:

Conventional baseboard hydronic distribution
systems are most common and these are designed for water temperatures in the 180 F range, well above the saturation temperature. I agree.

The heating system as tested combines space heating and domestic hot water loads using an indirect, 40 gallon tank with an internal heat exchanger. Tests conducted during the summer months showed that the return water temperature from the domestic hot water tank heat exchanger is always below a temperature which will provide condensing operation of the boiler. I feel the use of the domestic water tank skews the test somewhat in favor of the condensing boiler.

The results included in Figure 26 and 27 show that the condensing boiler yields higher efficiency than the non-condensing boiler in actual use. However, the increase in efficiency achieved with the condening boiler during the heating season is smaller than might have been expected.It comes as no surprise that the condensing boiler has higer eff, but most of the savings in this study seem to be in low demand situations and operating this unit in the summer for domestic hot water is not a fair comparison in my opinion.

The primary conclusion of this work is that condensing boilers can achieve energy efficiency benefits, even when used in homes with common baseboard radiators by incorporating a reset control which modulates the water temperature supplied to the baseboards with outdoor temperature......This of course depends upon the oversizing of the baseboard convectors relative to the design load of the home and the excess air level on the burner.The report seems to indicate in several places that adding baseboard or convectors will be necessary to provide adequate heat. The study was to determine what percent of the year that savings can be obtained, not if an existing system will function without adding additional heating units.

One must keep in mind the number one primary purpose of a heating system. It is to keep the occupants comfortable. Energy savings can be a very important factor, but if you install a system that can not keep the owners comfortable, they may use any money they saved on utilites to hire a good attorney to come back and sue you.


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