Saving heat by insulating the boiler pipes?

[Don2222]

Hello

We just installed a Buderus G115WS to save oil but all the pipes connected really radiate alot of heat! There is all kinds of different pipe insulation like Foam, Rubber, 1/2 " and 1" Fiberglass with white paper.


The pipes get very hot. Has anyone done this? Does it save money?


So far I tried insulating the Header Manifold with Fiberglass and Zeston2000 fittings for the 90 degree black iron fittings in the return line and using Reflextix Foil Tape I got at home depot.
See Link http://www.specjm.com/products/pvcpipeaccessories/zeston2000.asp

See pic below.

 

[in hot water]

It should be required in my opinion. It's code in many countries. The idea is to move the energy where it is needed and desired, not left behind in the mechanical room. Often times mechanical rooms have combustion air grills and that heat energy ends up outside. Or pulled up the flue with the diverter hood on the boiler.

Fiberglass is a common product. I like a melamine product called Techlite.net with the hard PVC jacket.

If you go with black rubber be sure to select a product with the proper temperature rating, usually called HT for high temperature. Stay away from the "box store" foam insulation or you may end up scraping off a sticky mess.

Hot water recirculation lines are another, often ignored, insulation potential.

hr

 

[btuser]

I like the fiberglass, but go to a supply house because HD is expensive. Like all insulation there's diminishing returns. I took my cue from my water heater and insulated 10' past the boiler, up to the flowchecks . Save money? A good piping job with heat traps and flow checks will save you more money than insulating a bad piping job. I put flowchecks on each zone, but noticed my supply header still was warm all the time. When I repiped for the new boiler I put a flowcheck on the supply and it made a huge difference. One side will read 140f and the other will read 80. Now the header is cool untill there's a call for heat.

 

[Don2222]

Hi BTuser

I have 3/4" Sweat Checks on each of the 3 zones but the supply comes out of the boiler and up to the ceiling and thru the expansion tank before it breaks off to each zone and the sweat checks.

So my question is where is your sweat check? Also can I do any better than that?

I also have a heat trap right off the top of the Indirect water heater. Plus I added a DHW Expansion tank on the cold side into the Indirect water heater so the cool water would be pushed out the bottom of the tank when the water was heated and expands.

Thanks


See Heat trap with Heat Nipple and DHW Expansion Tank below

 

[btuser]

I've got Taco 007 with intergral flow checks. I was still getting gravity flow out of the boiler and into the header before the circulators, so when I repiped my boiler I added a 1 1/4" flow check on the supply side header. It keeps the header cool when there's no call for heat.

I did all the near-boiler piping before the boiler, and in order to keep things simple on the change-over I piped my indirect as the 1st zone off my header. That way it was a simple disconnect from two unions and I could hook up the new boiler. Problem now is every time there's a call from the indirect the header will heat up. Hopefully next Summer I'm going to be tinkering with a DHW solar setup, so I have a chance to pipe directly to the boiler for back-up.

 

[DBoon]

I did this a couple of years ago on my boiler pipes. I used the dense fiberglass with the white covering - I think they were rated for R-4. I calculated that I would save about 15-20 gallons of oil a hear. The basement temperature in wintertime dropped about 2 degrees F after compared to before.

 

[Don2222]

Hello

Thanks DBoon for the numbers, that sounds great!


BTuser, I like that idea of the 1.25" Flow check. Can u post a pic of that so I can understand better?

Thanks

 

[peakbagger]

My parents switched over to a Buderus a few years back. I was surprised that the unit seems to heat up the mechanical room more than the prior furnace. The system was switched over from zone valves to zone pumps which means more piping in the area. I have insulated what I can reach but the installer wasnt very careful and some of the pipes are right up against a concrete exterior wall. The installer also installed a "hot water maker" (zoned hot water storage) and piped it so that it would thermosyphon. In general the boiler is a nice piece of equipment and their heating bill has dropped 20% but the installer compromised some of the efficiency with his installation practices.

I think the insulation I did install made a difference.

 

[dogwood]

Where are you all running down your pipe insulation. Locally? Or do you have an internet site that you go to. I've been trying to run down reasonably priced pipe insulation of either the fiberglass or black rubber type for 1.5 inch pipe. Local supplier didn't have any wide enough. Any impression on which type would do the better job or any other pluses or minuses for either type?

Mike

 

[Don2222]

Hello

My experienced boiler man said Fiberglass is still the best and I believe him. Home depot has the 1/2' thick in many sizes including 1.5". However F.W. Web contractor supply has the good 1" thick fiberglass pipe insulation in many sizes but costs 2x home depot's price. Looks like you get what you pay for in this case!

 

[dogwood]

I'll check out Home Depot. Thanks Don.

Mike