System Temperatures

Thursday, November 26, 2009

4 PEX Fittings and the $10K Expander Tool

Well, it is the morning of Thanksgiving 2009, and I am putting the fittings on My 1.25" PEX. As most know, any PEX above an 1" id requires special tools to expand the tubing to allow the fittings to be inserted. I planned for this in advance, but we all know about best laid plans and murphy.

So far the majority of my plumbing supplies have been purchased through our local supply house Weinstien Supply. Since I purchased my PEX there, they also were able to locate and rent me the WIRSBO expander tool required to install the fittings. The tool rents for $100/week and came in 2 weeks ago, but I was travelling on business, and was not able to pick it up. So....they rented it out to another customer of course. I had to wait until last night for it to be returned so I could get it before the holiday weekend shut-down. I really wanted to get this step done before now, but as someone smater than I said(Bill Clinton I think) "It is what it is". Fortunately, the sales rep, Ed got me the tool, and even dropped it off on his way home so I could get the fittings done this weekend.

The tool is really slick. It is a battery operated hydralic expander that takes all of 1 minute to expand the PEX enough to insert the fitting. I had 4 fittings to install 2 in the Garn Barn, and 2 in the basement. It took me all of 20 minuts to square cut the tubing, and install the fittings. I'm glad that is now done. The cost for 4 fittings installed, including the fittings, ProPex rings and tool rental was $40/fitting. Not much I can do about that, just pay up and move on!

Sunday, November 22, 2009

The Garn Barn siding is done! ;-)

The GARN BARN is now sided, with a window and a door. This is a major milestone.

We decided to use T-111 siding on the building, and stain the siding to match our house. We we fortunate that Global Warming has given us a mild November here in eastern PA, so we were able to stain our T-111 with 2 coats BEFORE is was nailed up. After the T-111 is up, I will go back over and seal a paint the nail holes.

Now that the shed construction is complete for the most part, the final phases of our project can move forward. They include:
  • Rough-in and complete the electric and control lines.
  • Finish the installation of the GARN Blower, controller, exhaust,vent.
  • Complete the plumbing of the Primary Garn Loop, and The Secondary Loop for the House.
  • Complete the House Plumbing which includes installing a 50 Plate Heat Exchange
We took advantage of another mild day to finish the rough-in of the Electric Service, and the Data lines. We ran 4 - 6ga USE direct bury lines for electric service to the GARN BARN, and ran 4 - CAT5 lines in conduit for data and control. The CAT5 cables will be a foot higher in the trench to provide some noise isolation from the 60 Hz electric lines. We brought both cable runs into the basement through the floor joist above the foundation to avoid another 12" hole in the foundation. Life is a lot easier drilling brick and 2x12s then 12" of concrete. But, I still had to rent the drill and bits from Action Rental in Allentown,PA. We had a 15% off coupon that eased the pain.

Sunday, November 15, 2009

Insulating the GARN

With the PEX tubing done, I now had to insulate the GARN before the siding could be finished. We decided to use rock wool which has an R-value of almost R-4/inch. Our local supplier in Lancaster,PA, Specialty Products and Insulation sells a product they manufacture called RidgidFlex-1000.

They take rock wool and attach it to a Foil backing to form 2" thick X 3' wide batts that come in 20' lengths. That is the perfect length to wrap the GARN. My goal was to insulate the GARN with approximately an R-32 Value. That meant 8" thick, or 4 wraps with the Ridgidflex. After each wrap the seams were taped, and the next pass would overlap the seams from the previous wrap. Once the final wrap was completed, I anchored a 2x4x10' along each edge and secured the facing under the 2x4 to keep the entire wrap tight.

There was enough of the insulation left after cutting batts to length to insulate both ends of the GARN to the same 8" thickness. That step will be finished when the building is completed, and the system plumbing has been completed. Access to both ends of the boiler will be much easier without the insulation in place.

Thursday, November 12, 2009

Spray Foam Insulating the PEX

Well, it is the final week of Bow season in eastern PA, and the bucks are running around like idiots trying to "Hook-up". I had to make a choice hunt or check items off the GARN Install list. I chose to do a little of both.

The PEX requires waterproof insulation in the trench, so after some research, and recommendations from a fellow GARN enthusiast Jim K. I chose to spray foam my PEX lines. The contractor, Terry, of Spray Foam Insulators in Tannersville,PA did a great job.

We had everything ready, with foam board down the entire length of the PEX andTar paper underneath the tubing. All he had to do is connect his sprayer to the 220V line in the barn, and he was up and running. The sprayer sprays the 2-part liquid at approximately 120F and on contact with air and the surface it expand to 30X the liquid volume! The foam hardens in about 10 Seconds and is completely waterproof,airtight and soild as a rock.

Terry said he spayed approximately an R-30 coating. That is far better then any pre-fab insulated PEX you will find on the market. The cost of the spray foam was roughly $6/foot, and the PEX was $2.90/foot, or $5.80/foot for supply and return. So our cost for the complete job worked out to $12/foot for dual PEX insulated. Significantly cheaper with a higher R value than any pre fab solution on the market. Time will tell, but I feel this is the best way to do this phase of the job. After we are up in running the tru test will be if there is any temperature drop from the GARN BARN to the house. The goal is 1 degree or less.

Monday, November 9, 2009

Core Drilling the Foundation for the PEX

The next day we rented a diamond tipped core drill and drilled two entry holes in the house foundation. The drill did a very nice job, and we were done with both holes in about an hour. Fortunately our local rental store rented the unit at a 4 hour rate, so we could save a little.

We bored 2 - 2.5" diameter holes. One for supply, one for return. The extra area between the PEX and the foundation will be filled later with insulation.

The core drill was worth every penny to get the job done quickly. Our foundation is poured, and 12" thick. The only difficulty I had was getting the hole started, and keeping the hole on a level plane. If keep the hole level was important, you can rent a drill that mounts to the wall. Of course for a higher fee! Since we a filling the hole with water tight spray foam insulation, level was not a big issue.

Sunday, November 8, 2009

Putting the Pex in the trench.

The weather today was perfect for working with the PEX so we decided to get the tubing in the trench. We designed the Primary and Secondary hydronic loops with TACO's HSS program, and determined 1.25" PEX would supply sufficient BTUs to the house load, with minimal head loss, and reasonable cost per foot.

We used WIRSBO hePex, since the boiler manufacture requires Oxygen Barrier PEX for the installation. The 1.25" is a stiff to work with, so the 70F degree day we got on November 8th was perfect to warm the tubing up, and make it easier to uncoil and lay out.

Once we had the 2 pieces cut and marked as supply and return, we fished them through the conduit into the shed. I used a corrugated drain tube
to provide access into the shed for the PEX once the pad was poured.

We put 2" pink board foam insulation in between the supply and return tubes the entire length of the run. This was done to minimize parasitic heat loss between the supply and return water.

Thursday, November 5, 2009

Framing and Trenching

Now that the GARN is on the pad the framing can begin. The Shed portion is framed with 2x4s on 16" centers. Most likely we will fill the bays with R-13 batts to help minimize the standby losses. We will wait to side the building until the length of the GARN in insulated.

We can now finish our trench between the shed and the house. The length of the trench is about 90 feet. We trenched down 3 feet to put the supply and return lines below the frost line.

The trench will also have the electric for the shed service, and a conduit for data and control lines.

At one point we did only go down about 2'6" where the trench crossed the cable and electric service. I will add 2" of blue board insulation at that point to ensure we are well insulated from freezing.
The next day the weather held up, and we were able to get the roof on the shed side of the building.