steam

paul_91

where is the best place to install your aquastat on a hot water zone off of a steam boiler using a plated heat exchanger?

chris_69

Related question: What kind of Aquastat?

I've got the same setup (hot water loop off a steam boiler, plumbed per Dan H's instructions). Right now there's one thermostat that runs the boiler when the steam zone calls for heat; the hot water zone circulators are on an outdoor reset control so they run whenever the outdoor temp is below the set point.

The house is comfortable everywhere. But, the duty cycle on the boiler is very light (old house; over-radiated). So, the circulators on the hot water loop spend most of their time running pointlessly - circulating cool water from the idle boiler through the zone.

What I'd like to do is add a thermostat in the hot water zone, and an aquastat to the boiler. I think what I want is this:

Burner is on whenever the steam zone is calling for heat AND when the hw zone is calling for heat AND the boiler water is below high limit. Circulators are on whenever HW zone is calling for heat AND the boiler water is above low limit.

So I think this means I need to put -- in parallel with the existing thermostat -- the new HW zone thermostat and the high limit switch (open on rise) on the aquastat. And I need to ditch the outdoor reset controller, and wire the circulators to the low limit switch (close on rise).... oops, but I only want the circulators on while the HW thermostat is calling for heat....

There must be a control for this - this is just like domestic hot water run off a steam boiler, isn't it?

JohnNY

Paul,

The aquastat goes directly into the boiler.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"