Indirect on steam. Purge required every day.

1890ish

I have single-pipe steam heat and an indirect hot water tank.

I've been purging excess water every day and I've been trying to diagnose it over several days. Calling in a repair person has always been hit or miss for me. That's why I appreciate this wall. I will call a pro if we need to replace the indirect tank.

Last week, I serviced the feeder myself with a VXT service kit. And yet I am still purging 1-2 gallons of water from the boiler daily!

I created a simple diagram of my system. I think it may be a problem with the indirect tank. The boiler is a weil-mclain, and the tank is a superstor 60-gallon from 2004.

I've been messing around with the honeywell pressuretrol to see if changing the cut-in/cut-out has any effect, but I see no difference over 3-4 days, making one adjustment per day and measuring after 24 hours.

How could I diagnose whether it's a problem with the indirect tank? Would cutting off water to the Superstor or shutting off the main house supply be an effective way to test for leaks in the tank? I can live without water overnight or for 24+ hours while traveling.

mattmia2

Turn off the potable supply to the indirect and relieve the pressure in the hot water and see if you still are gaining water. I assume you confirmed the manual valves are holding when you serviced the auto feeder and you have all the valves to that off, both the manual bypass and the valve to the solenoid valve.

EBEBRATT-Ed

You have 3 places water can get in the boiler:

The indirect coil is leaking or

the auto feed is leaking or

the manual bypass is leaking

The pressure control has nothing to do with this.

First shut the cold water inlet to the indirect and open a HW faucet to relieve the pressure. Mark the water level in the gauge glass then let it sit over night and check the water level.

The other two places are the manual bypass or the water feeder. Those pipes chould rise to room temp with the boiler not running. If you check them in the morning and they are cold they could be leaking by.

20 years out of an indirect is pretty good.

1890ish

Ah, good advice!

Question about relieving the pressure by keeping the HW tap open. Do I leave it open all night?

The problem I have with checking the feeder is that there is no isolated shutoff for the feeder, as I illustrated. I had to shutoff water for the entire house to service the feeder.

I thought I'd be able to do this tonight but everyone is freaking out about travel tomorrow, so I'm going to wait until after Thanksgiving, because I want to be sure everything is as normal as possible in the morning.

mattmia2

I'd add the missing valve to the feeder. It could be calling for water because the level is dropping sometimes for some reason.

1890ish

I turned off the cold water feed to the indirect tank and relieved the pressure by opening a hot water tap and leaving it open. Still had to purge a lot of water from the boiler the next day.

? What does this mean ?

109A_5

Hello 1890ish,

I'm assuming the VXT is not logging any new water.

If the coil in the indirect is leaking and the water level is higher in the tank than the boiler water level it still may migrate to the boiler, although probably at a slower rate.

Disable the DHW so the boiler won't start with a DHW call, disable the circulator too, so it can't pump into closed valves.

Close the two Red circled valves, see what happens. Assuming your valves are good, if it still over fills the boiler your feeder or feeder bypass is leaking. For maintenance and diagnostic purposes and also previously recommended, add a shut off valve at the Red arrow.