Weil-McLain EG (steam) with indirect water heater?

JohnNY

The EG I&O manual only refers to using the tankless coil under its "optional indirect water heater". To use an indirect water heater means using 2 heat exchangers. Yes, I could go with a storage tank...if I could find one on the quick.
I don't feel my artistic vision for DHW is being accommodated with these tappings:

EBEBRATT-Ed

Guess I don't understand the question. Are you looking for boiler tappings for an indirect?? With an EG on steam how about the skim tapping for the supply and the return could go in where the steam return goes in. Use a tee and a double tapped bushing to extend it inside the boiler if you need to.

EdTheHeaterMan

I prefer the tankless coil idea for a steam boiler to heat ANY water zone. I used that idea when replacing an 85-year-old MILLS with a new WM series 80. The 3 offices and 2 restrooms were on the same zone as the Sanctuary. Sanctuary used 1 say a week while the offices were used multiple days per week. There are 3 large 4" zone valves on the 3 different sections of the building, and heating such a large zone 1600 SqFt to 70° was inefficient for just 400 SqFt of office space/restroom.

The new boiler will provide a separate 400 sq ft zone of baseboard with the thermostat in the secretary's office. That baseboard would be connected to the optional tankless water jacket in the steam boiler. The zone would operate a circulator and the burner to heat the smallest zone in the building complex. The burner would operate thru an additional high limit set at 180°F this would keep the burner from steaming if only the offices were in use.

I believe this is more efficient than steaming the entire Sancturay and it substantially increased the comfort in the winter months (since they were only heating those rooms to 55° except on Sunday. By using the "Tankless Coil" as the source for the baseboard heat, it also included an expansion tank, circulator, 30 PSI boiler relief valve, water feeder, and air separator. Now all the malarkey needed to keep the steam boiler water in the baseboard loop from becoming air bound is unnecessary.

I believe this will work for you with the indirect water heater zone. You will need to order the optional tankless coil and a few more components for that zone. If you want to go cheap economy you could try to follow the other method. and using the D and C tappings to feed the indirect.

Just my thoughts.

Yours truly,
Mr.Ed

JohnNY

EBEBRATT-Ed said:

how about the skim tapping for the supply

The skim tapping is too high.

@EdTheHeaterMan I generally agree with you and much prefer to use the clean BTU exchange of the tankless coil but Lochinvar offers a Lifetime Limited Warranty with their indirects and so I'm inclined to sell it as a DHW option with a new boiler installation. That leaves me with having to use either two heat exchangers or abandoning the coil in the indirect and just piping the tankless into the domestic side of the tank. Annoying.

fricard

Does it have to be a Weil McClain?

Steamhead

Take your supply for the indirect off tapping P, then run the return into the main return tapping between the boiler and the Hartford Loop. Be sure to use an aquastat to keep the boiler from making steam when only the indirect is calling. I like the White-Rodgers 1145-33 with its 11-inch probe, which can reach all the way into the boiler section if you mount it on a tee and nipple in tapping P.

mattmia2

JohnNY said:

EBEBRATT-Ed said:

how about the skim tapping for the supply

The skim tapping is too high.

@EdTheHeaterMan I generally agree with you and much prefer to use the clean BTU exchange of the tankless coil but Lochinvar offers a Lifetime Limited Warranty with their indirects and so I'm inclined to sell it as a DHW option with a new boiler installation. That leaves me with having to use either two heat exchangers or abandoning the coil in the indirect and just piping the tankless into the domestic side of the tank. Annoying.

You could just get a storage tank and use the tankless coil to heat it.

JohnNY

Steamhead said:

Take your supply for the indirect off tapping P

Unfortunately that P tapping is only on the EGH. This is not the first time I've been tripped up by the differences between EG and H.

JohnNY

mattmia2 said:

JohnNY said:

EBEBRATT-Ed said:

how about the skim tapping for the supply

The skim tapping is too high.

You could just get a storage tank and use the tankless coil to heat it.

Yes. It's what I frequently do, but I've been trying to take advantage of Lochinvar's "Lifetime Warranty" as advertised in their literature as a selling point. As it turns out, they have loose definitions of "lifetime" and "warranty" anyway. So, I'm retooling.