Air locked zone?

docjone5

Hello I am a homeowner who had service done on my heating system. I have a Lochinvar KBN151 Knight system with 6 zones. After the tech left, a few days later my number 1 zone stopped working. Each zone has a Grundfos pump on it. I tried to bleed each register at the bleeders and would get a little bit of water then nothing and now nothing at all.

Is there a way to bleed the whole zone at the pump?

Thanks,
Dan

icesailor

If what you describe happened, you need more water pressure in the system. It probably needs to be at least 15# to 18# to fill the system properly.

Gordy

What work was performed on your system?

What's the system pressure read?

If your not getting water, or air when bleeding then the pressure is to low. Should be around 12-15psi. If the pressure is low turn on the make up water valve if it's off to the pressure reducing valve you should hear water flowing into the system.

If system pressure was to low then you will have to keep the pressure up while you bleed the loop until your rid of all the air. Then get pressure in range.

docjone5

I'm no pro on any of this but this is what the system gauge is showing and looks like the temp and the pressure is low.

docjone5

The part which was replaced is the white PVC thingy in this picture. Not sure what it is or does but the guy said it was cracked and leaking water. Not sure it is related to the overall problem I am having with the zone not heating though.

icesailor

The white thing is a separate issue.

You have less than 10# showing on the gauge. It needs to be more with a Gianonni heat exchanger and system.

Paul48

The pressure is too low. It takes a certain amount of pressure to keep the system filled to the highest point of radiation. The fresh water supply to the boiler should have an auto-fill regulator on it. It should maintain pressure on the system of around 15 psi.

docjone5

Thanks for the info and replies, what would the auto-fill regulator look like? If the system is not getting enough water how do I add more/ increase the pressure? My other question is how would the system lose pressure? Leaking pipe somewhere in a wall (I hope not)?

Gordy

That pvc is a,condensate neutralizer. Should of had nothing to do with effecting system pressure by being replaced. Can't believe the tech did not even check things like that in a look around the boiler.

Gordy

There should be a cold dhw pipe to the boiler with a **** off valve then the PRV with a lever on top. If the the domestic valve is off turn it on. Should be able to hear water flowing into the system. If not, and the pressure does not rise flip the lever open on the prv until you get the pressure up.

Paul48

Here's one of Watts's....http://media.wattswater.com/1910265.pdf
Systems will lose water, with no apparent leaks, over time. Systems that are low in pressure, and don't have proper air elimination in place will become air-bound. The air will always work its way to the highest point in the system.

docjone5

I'm out here in the Buffalo NY area and there is no one that really knows this Lochinvar setup. The "authorized" service provider Lochinvar gave me out here did not seem to have too much of a clue. I originally called because the LCD on the Lochinvar said to get maintenance and the guy didn't even know how to reset the maintenance service message.
He did know how to charge six hundred dollars for the condensate neutralizer parts and labor though....

docjone5

Ah I know where that PRV valve is! I am heading into the basement now to see what I can do (break)....so, where did the pressure (and water) go to cause the pressure in the system to drop? Also why are other zones not affected?

docjone5

So flip that valve on the PRV and then back down? Then bleed the registers?

Paul48

No...that's city pressure. Is there a closed valve feeding the PRV?

docjone5

Ok here is what the guage reads now, which to me looks like 15. Do I add more water?

docjone5

Guage pressure

Paul48

How did you get it to 15?

docjone5

Also no closed valves seem to be leading to the PRV. I flipped the lever on the top of the PRV and I heard water going into the system.

Paul48

The PRV has to be adjusted, or when you go upstairs to bleed, it will just go back to where it was before. It is about 17 or so now. Go ahead and bleed it, then check the pressure.

docjone5

To get it to 15 all I did was flip the PRV lever up for a few seconds and then back down.

Paul48

That's a bypass lever. You have to be careful with that. It allows city water pressure into the system. As soon as you put it back down, it is then regulating pressure( in your case) incorrectly. Go ahead and bleed the affect zone. The pressure will go low again, then you need to adjust the regulator.

docjone5

So far I'm bleeding the registers. There are 6 is this darn room. Will I eventually feel hot water come out of these bleeders?

Paul48

If you've let that blast of pressure you put in there out, you won't get anything more out. Check the pressure again.

docjone5

Pressure dropped down to around 10 again so I got it back up to 15 again. No hot water still from the bleeders though

Paul48

Have you read any of my posts?

docjone5

Sorry to sound dumb. I am trying to understand and I do VERY much appreciate your help and guidance. Pressure is still at 15 and I am still bleeding registers. One thing I noticed is now that the pressure is up the grundfos pump on this zone sounds noisy.

Paul48

Did you adjust the pressure on the PRV, as opposed to just flipping the lever again? Read the directions on the watts link I posted.

docjone5

So when you say adjust, do you mean follow the directions to reset the regulator?

Gordy

Yes.

Also do your bleeding with the pumps OFF. Start at the farthest emitter, and work your way back.

Bleed until you get water then move to the next. Making sure the whole time the psi is up at 15. Every time you bleed your letting pressure out of the system sometimes faster than the prv can keep up.

Once everything is bled turn on the system, and see what happens. If you hear gurgling in a zone bleed again.

Once you are done I would keep an eye on the pressure for a week or so. If the water is on to the system all the time you may have a small leak some where. A way to tell is once everything is going good shut the supply valve for the water off. If you lose pressure there is a leak somewhere.

docjone5

Ah ok. I was bleeding with the zone 1 pump on.
The other 5 of my zones are working fine I have heat in them. Is it ok to do this with the system running and just zone 1 pump off? (Zone 1 is far left)

icesailor

IMO. hold the lever up on the PRV until the pressure on the gauge shows 25+ #. Turn on the system and the zone that isn't working. Watch the pressure. If it drops to below 15# while trying to get the zone to work, lift the lever again and raise the pressure to 25# again. Often, just raising the pressure in the system will cause the zone to flow. If the system won't hold 25# and drops immediately, look for a leak on the upstairs. If it has been cold, and the upstairs pressure isn't high enough or the upstairs zone isn't used, a pipe may have frozen.

Check for leaks.

Get the zone working before you try to adjust the pressure if you don't know how.

docjone5

Thank you all for you knowledge and advice. I am wondering if indeed I could have a froze pipe in that zone (whole place is PEX). While we do use that zone often the thermostat is set to go down during the day so I guess since here in Buffalo it's been below freezing for at least 3 weeks it could be possible.
As of now the pressure is at 15. I bled all 6 registers in zone 1 and am getting water out of each. I'm gonna knock off for tonight, I have been beaten for now.
Thanks again for your brain power!

docjone5

I woke up this morning and checked the pressure in the heating system. It has not changed from 15psi that it was last night.

The thermostat was left on set to 70 and the room was down to 62 degrees this morning. The Grundfos pump for this zone has been noisy now ever since I upped the system pressure from 10 psi to 15 last night. I am getting cold water out of all 6 radiator bleeders in this zone so I am not sure if I have a problem with something else.

When I set the thermostat in that room to heat I can see it is "talking" to the Argo relay (or at least the green LED is lit) so I think everything is ok up to that point (I also swapped that zones relay with one of the other zones to make sure the relay was ok).

Also if I put my hand on the Grundfos pump for this zone it is hot to the touch but the feed and return for this zone are not hot.

If there was a frozen pipe on this zone would I still be able to get water from the radiator bleeders?

Thanks.
Dan

Hilly

The install seems like some level of care and professionalism went into the install judging by the few pictures you have up. Is the originally installer not available to do your service for you?

icesailor

The supply r return pipe can be frozen and you will get cold water out of the emitters.

The colder it gets,, the less you want to turn your thermostats down. Especially in unused zones or second floor zones.

If the circulator is hot and making noise, it is cavitating but not moving water Get out the hair dryer or paint removal heat gun and start following he pipes. Don't overheat and melt paint. Especially where they get to an outside wall. Warm the pipes so you can feel the warmth after you take the heat gun away. If it gets cold immediately, it is/was frozen. If you have baseboard on the second floor on an outside wall, put the hair dryer on the bottom so the air blows UP into the cabinet.

Because we can't see all around the boiler, it just might need to be purged. Try heating it first. Purging can be complicated.

docjone5

Thanks for the replies. As for the original installer, I called him several times and always get the "call ya back later to setup an appointment"...and never a call back.

I tried a few things with heating the pipes. I have 2 infrared space heater and ran one in the room that is not getting heat to get the room up to 72. I ran the second in a (cold) back hall where the feed line goes up and then ran a 3rd small space heater blowing on the pex in the basement where it goes up into the wall with no luck.

A new thought I had is perhaps the Argo 6 zone switch relay has a bad board? I was wondering if I was able to take the wires powering a different pump zone and attach them to the non working zone maybe that would tell me if the Argo board was messed up for that zone if it then began to work.

icesailor

Hot air rises. Some might say that is me. You can heat the room to any temperature you can. Its still cold on the floor. Put the heat gun directly on the pipes on the floor.

As far as the pump running, if it is vibrating, and stops when you turn off the power, the pump is working. You may need to purge it. You will have to purge it through that complicated and un-needed by-pass.