Replies

1. 
   TLRice | May 16, 2002 02:23pm | #1

   In an installation that uses radiation, you will add 15% for "pickup" and piping losses. This would be in addition to the heat losses but not added on to the DHW, which will have to be added, as well. If using the Burnham Alliance indirect water heater, like the AL40A, add 133,000 to the adjusted heat loss (245 MBH total). This establishes the minimum, pick the boiler that meets this.

   I am not familiar with the V8 series, this is a cast iron, oil fired boiler? I have info on the V7, and in that series, you would use the V77. This would be conservative, and there is room to downsize based on "diversification".

1. 
   Wet_Head | May 17, 2002 11:17pm | #2

   Tim, buddy, please learn how to size boilers before you give advice.  You are so wrong...  somehow I think you are not a fan of hot water heat... I base that on all the misinformation I see you give out on heating issues.

   This is not meant as a personal attack... rather an encouragement to get your facts straight.

   For the record, your DHW add on is totally wrong.  If you want to know why just ask.  If you simply want to argue... I won't respond.

1. 
   KCPLG | May 18, 2002 02:56am | #3

   Wet Head

   I read Tims post and wondered how I've been putting in all these undersized boilers (according to his formula) and haven't got any callbacks from my customers shivering in their underheated homes.

   Kevin

1. 
   Wet_Head | May 18, 2002 09:20am | #4

   Thanks...

2. 
   TLRice | May 20, 2002 03:35pm | #5

   That info came straight out of the manufacturer's literature. The 15% adder for radiant is also straight out of the Burnham boiler data, (DOE heating capacity + 15% is the I=B=R net rating) and is standard practice, has been done longer than I've been doing this stuff. How do you size boilers? I am always open to listen to someone that knows more than I. So, I'm asking.

1. 
   Wet_Head | May 20, 2002 10:23pm | #6

   I use Burnham's software.  I also have software from Wirsbo, Rehau, Slant Fin, and 3 others!

   I always put DHW on a priority circuit leaving it free to devote itself 100% to DHW as long as that takes.

   I like the way you came back and would love to discuss it further but gotta run right now...

1. 
   TLRice | May 21, 2002 02:55pm | #7

   You were right in you observation that I am not a great fan of hot water heat, at least not in residences. I like forced air, mainly because that is what I learned first and deal with the most. Also, having lived in warm and humid climates all of my life, AC is not usually considered an option. Two systems are more complicated and expensive than one. I like and use hot water and hot water/chilled water systems in larger buildings.

   I believe, as it seems you do, that the flaming and confrontational posts are best left to the Tavern. I bet I know stuff that you don't and I am certain that you know stuff that I don't.

2. 
   Wet_Head | May 21, 2002 06:25pm | #8

   Yeah... but maybe I don't want to know about furnasties vomiting out scorched air!  LOL

   Just kidding.

   Seriously... I hope we can learn a lot from each other.  I am highly prejudiced for the gentle comfort and increased health hot water can give.  But I will be the first to say it is not always the best solution.

3. 
   TLRice | May 22, 2002 03:15pm | #9

   I love my warm floors (I have heat under tile in all bathrooms) but on a 90/90 (that would be 90 degrees and 90% relative humidity) day my furnasty is "vomiting" out nice cool, dry air. I understand the prejudice against forced air because I have seen many poorly designed/installed systems.

   You'll have to explain the increased health that hot water (heat) can give.

   IF I were building new, and money was not limited, my ideal home would have radiant floors, an indirect DHW and forced air for ventilation and cooling/dehumidifying/humidifying.

4. 
   ahneedhelp | May 22, 2002 06:44pm | #10

   After several years of being stubborn against installing any type of ductwork in our house, we bit the bullet and went for a properly sized and configured central A/C, mainly to handle the very short period of high humidity and heat that hits us maybe 2-3 months every year.

   We have hotwater baseboards. Although in theory inferior to infloor radiant, we wouldn't trade it for anything else.

   As for the central A/C, it's been a very nice compliment to the heating system and the contractor did an excellent job. We can barely hear it when it's running and the grandparents visit more often.

   More folks could consider dedicated systems for handling heat and cooling/dehumidification separately.

   We opted against going with a heatpump as a backup heatsource in case the gas boiler setup has problems.

   I try to stay on top of things and make sure it's in good working order.

5. 
   TLRice | May 23, 2002 03:24pm | #11

   When I bought the house I now live in, there was only electric baseboard heat and a few window units. My electric bills were obscene (one January the electric bill was almost $400). Mold would grow on just about anything that did not move. I had a 90+ furnace with 4-ton AC installed for $10,000 and now heat for about $40-50/month (depending on the price of LP) and can dehumidify the whole house, when necessary.

   As long as the ductwork and registers are sized conservatively and the furnace/blower are enclosed/isolated from the living space, a good forced air system is unnoticeable. At least mine is. I really liked and planned on radiant floors, but as a practical matter in a "live-in" retrofit, and renovating a house room by room, (plus the cost of 2 separate systems) I took the easy way out.

6. 
   ahneedhelp | May 23, 2002 04:01pm | #12

   I'm with you.

   We can all agree with Wethead that it all depends on each situation.

   Personally, the whole hydronics thing is like playing with a grown-up toy set and I love studying the distribution piping schemes around the boiler. Some installations look like an engine room in a luxury yacht.