Final (?) configuration of my system upgrade

Harold

A way too long post, but an overview as best I can provide for my (hopefully) final configuration plan for my system. Across various posts of mine, there have been questions from helpers here. In this quite long post I have tried to cover the likely questions in one place. And I am attaching some pictures. The whole enchilada. I apologize for the length, but please go through it.

I have finally, with significant help from this forum, settled on what I am going to do when replacing the leaking WM Ultra boiler with a Weil-Mclain EVG 110 (CSA output 101,000 Btu) with a stainless heat exchanger. I would also like to note that WM has been very helpful, and has excellent customer support. I was concerned about the capacity. I have always thought (wrongly) my existing boiler was the Ultra 105. I recently realized it was really the smaller one. I became concerned with short cycling since I had already purchased the EVG 110. The numbers below show the EVG 110 is not oversized for full implementation of the system. May even be too small; but I am not going there.

Total Flow Rate: 12.2 USGPM
Maximum Head Loss: 6.8 ft(H2O)
Total Loops: 38
Total Manifolds: 5
Total Zones: 2
Min. Tubing Required: 6058 ft
Total Load: 55,139 Btu/hr
Total Radiant Load: 42,548 Btu/hr

Total Unit Heat 319.0 From original design

Areas I don't think are covered in original calculations
Garage Floor 840.0 sq ft insulated everywhere but doors
Greenhouse 288 sq ft 16 KBtu minimum delivered heat
Pool 2600 Gal
At 74 F - Embedded heat Btu 160 Mbtu
Pool 5 Degree change 108 Kbtu
Pool Ventilation ???

Please, anyone, provide any suggestions, critiques, alternatives, or "wow, that's really stupid"; responses. You can't hurt my feelings. From the amount of research and reading I have done, I almost think I can do this. Sigie and Caleffi tutorials have been a massive help. I am an old engineer; but hydronics was never something I was interested in.

Assorted information.

There is an 80 gallon buffer tank between the primary and secondary loop. As piped, the buffer is actually part of the primary loop with a circulator in-line. On heating demand, the circulators for buffer, secondary loop. and boiler are activated. That might get changed. There are other potential loads, which probably drove this configuration.

The boiler can modulate down to 20 KBtu.

Piping will change.

I will replace 2 of the Grundfos UPS 15-58 circulators in the system with 2 AquaMotion AM55 smart variable speed pumps for DHW and buffer. The third current Grundfos UPS 15-58 in the primary loop will be replaced by a Taco pump that is included with the boiler to handle the primary loop.

For the secondary loop, a Grundfos UP 26-64 will be replaced by another AM55. This circulator was over sized. I will put stubs around the secondary loop pump to allow a second pump to be used in parallel. This is for the supply if the larger loads are ever activated. There is also a larger version of the AM pump. All the new pumps have selectable internal check valves.

The DHW pump will be moved from the primary loop to a direct connection to the boiler; before the boiler pump (per WM recommendations). It will have a variable speed pump supplying water to the DHW tank. The tank is around 60 - 80 gallons. I can't see the label because of a safety strap. My thinking is that by adjusting the fixed speed of the pump I can avoid any short cycling caused by DHW demand if it occurs.

Possibly reroute piping from primary loop to buffer tank to do closely spaced Ts on the primary. The current configuration makes the buffer tank coil part of the primary loop. It uses one of the circulators to control flow. It feels like that is the wrong approach. I think closely spaced Ts on the primary and a circulator would be the best way to get water to the buffer tank.Comments really appreciated on this point.

I have attached a couple of photos. The buffer tank is on the left. The piping to the bottom of the tank is essentially part of the primary loop. In the left photo, pumps you see on top near the ceiling, are for an unused heating coil in the range hood and the one on the right is DHW. Stubs are for various circuits not in use. The lower pump is the buffer pump. Input (top) is the primary loop. In another photo you can see that the pump feeds the input of the buffer tank and the return goes through a Y screen and then completes the primary circuit.

Add isolation valves as needed for maintenance.

Review isolation, drains, and bypass.

Existing bypass between supply and return in the secondary loop will be reconfigured with a valve in series with the bypass device. I am not convinced the bypass is needed with the new circulator. Sources vary on this point. But I will have options. The secondary loop source will not have another direct bypass connection to return flow. Only returns are from the zone loops.

Add a Caleffi Dirtmag at boiler. Refurbish existing air extractors. Pipe the output vents of selected air extractors to avoid dripping water on equipment.

Tekmar 262 controller will be replaced by the computer in the boiler. Three Tekmar 369 zone controllers will continue to be used with the boiler computer. There may still be a useful function for the 262; but I am having difficulty figuring out if that is true.

New WM sensors will be used for the buffer tank and the DHW tank. All provided and specified boiler functions, safety devices, and supplied accessories will be installed.

Before new boiler installation, system will be flushed with fresh water. After reworking, the system will be filled with protective additive. pH tested. I have an in-depth spectrographic analysis of my water. It seems to be fine for content and pH. No antifreeze. If an outside zone is activated later, I will install a heat exchanger for the specific loop with antifreeze. Pool will also have a heat exchanger.

I am still debating on using CrossManifold manifolds to replace two of the existing manifolds. I would have to buy two manifolds for each manifold I would replace. This is because of the much greater width of the CrossManifold. It adds significant cost and makes re-piping a bit trickier.

Thanks for your support guys.

kcopp

I would certainly hit the system w cleaner like Fernox or Rhomar.
Water alone will not do....
May be best to flush the system first add the cleaner, Let it run for a few days then flush again.
Looks like it attacked the Press O-rings pretty hard.

Harold

After trying to cover everything, I seem to have lost a piece about flushing. The water in there is not the antifreeze polluted water that caused the leakage. I am on my second leaking boiler core and moving to a new boiler rather than replacing the core again.

I have the cleaner here. I intend to drain the system. Refill with water and the cleaner. Run for a couple of days. Drain and flush with clean water before replacing the boiler. Drain for repiping. Then do a final fill with clean water and the chemical WM recommends for the operating system. Perhaps a bit of overkill, but I want to be sure any residual gunk is gone.

Harold

Does the relative lack of comments mean I have finally gotten it fairly right?

Harold

I have discovered a serious stupid move in my system upgrade. My fault for lack of rigor.

I am replacing a broken Wiel-Mclain Ultra. My original target was a Weil-Mclain EVG 110. Inadvertently, I actually had an existing Ultra 70 instead of the Ultra 105 I thought I had for the last 10 years. When I re-evaluated heat loads, The 110 actually seemed to be the way to go. I found significant heat loads not included in the original design.

Now, the stupid mistake.

I intended to use the EVG 110 and had initially downloaded the PDF manuals for the EVG 110, and used the documentation throughout the redesign. At the end of the design process, I did an examination of the piping and other devices that would need to be changed. I have essentially replaced all of the existing pumps, piping and non-WM controls in the area that would have to accommodate the boiler. The EVG with stand was a fitment issue with reconfiguration.

Result: Shortly before buying, I switched to buying an ECO instead of the EVG. I thought the only differences were the wall mount vs stand. Very very wrong. I don't really understand why this should be that way; but what is -is.

I took a look at the ECO documents, but everything I looked at seemed to be the same. So I just continued using the documentation for the EVG. Because I had made a lot of notes and highlighting on the WM documents. Really, really, bad move.

So. I have an installed ECO 110 that can not provide the necessary input and output control functions. Turns out there are quite significant differences. I have tried to find a replacement controller, but things WM are really quite hidden.

I need the control module for the EVG 110 to replace the ECO 110 control module. My guess (looking at inputs and outputs of both) and functions, is that the only difference is firmware. I find it unlikely that they have multiple versions with significant differences. Not worth multiple variants sitting on a hardware device. I have had no success finding an EVG controller. And I suspect if I could find one, it would not work on the ECO because a bit somewhere in the hardware has to define the model/version to the firmware.

I really really need the EVG control interfaces that do not exist in an ECO boiler. I would be happy (well not real happy) to buy an upgrade. But I have found no way.

Is there anyone out there that can help me with this dilemma? As installed; it does not work. A rather expensive screw up on my part.