VXT-24 keeps filling

Kjmass1

Brand new steam install last fall, highly regarding installer. We drained the boiler for some basement work, new gas line. I turned on the power switch and LWCO light turned on and it started auto feeding. After 5 gallons I hit the sight glass line and it won't stop. Looks like the dip switch is set to LWCO. We'd like to test the new gas plumbing but every time I turn on the power switch it keeps trying to fill. Anything I can look in to or bypass?

EBEBRATT-Ed

Its one of a few things. Either the Low water control is telling the feeder to feed when it shouldn't or the feeder is defective, valve leaking by or feeder relay stuck. Low water probe could be dirty.

Kjmass1

https://forum.heatinghelp.com/discussion/comment/1862908#Comment_1862908

If I shutoff the isolation valves for the feeder will it fire even if it's attempting to feed? Or will it not fire until it's stopped running? Just trying to test the boiler at this point.

Jamie Hall

Maybe. It depends on whether the problem is in the feeder or the LWCO. If the LWCO thinks the water is low — even if it isn't — the boiler shouldn't fire. In fact, you rather hope it doesn't — much better to have the boiler shut off due to a faulty LWCO than keep running dry due to a faulty LWCO!

On the other hand, if the LWCO isn't lying but there is something amiss with the automatic feeder, the boiler should run just fine. Just remember that you don't have any automatic feed…

Kjmass1

https://forum.heatinghelp.com/discussion/comment/1862915#Comment_1862915

Is there a preferred setting for finished basements? This certainly doesn't make me sleep well at night that it could potentially just keep filling endlessly. Boiler barely uses any water in the first place after last winter, has a nice drop header.

Jamie Hall

Preferred setting? No different for finished basements vs. unfinished — a dry fired boiler is a catastrophe wherever it is. But there is a preferred water level setting. For most boilers it is in the middle third of the gauge glass. There are a few where it may be higher, but never lower — and always in the gauge glass.

Many people don't have automatic feeders at all — though they are rather handy if there is no one who checks the boiler regularly.

109A_5

For example if these two valves are present and functional and closed no water will go to the boiler (even if it needs water).

You need to figure out which device is the problem. The LWCO (Low Water Cut Off) or the VXT feeder (electrical) or its valve (mechanical). Disconnecting the 'Feed' wire may help isolate between the two devices. An example;

https://hydrolevel.com/wp-content/uploads/2021/06/VXT-24-Instructions-web-0321.pdf

mattmia2

can you take some pictures of where the i'm assuming probe for the lwco is installed (i assume it is a probe type and not a float type)