Radiant floor heating setup gurgles?

[Stayouttadabunker]

Hi,
First I'd like to apologize if this is the wrong thread or forum.
I'm fairly new to this great website!
I am working on a maybe 7-10 year old 30 gal. hot water Lowboy heater
that is hooked up to a slab that covers roughly 350 square feet...
It's not sending heat up to the floor slab area.
My guess of 400 sq. ft is probably overstated -it's actually covering
less area as I haven't measured it.
It is filled with a mixture of Glycol (red anti-freeze)
and I'm having a bit of trouble trying to make sure the tank
and lines are filled with no air pockets.

Every time I open the valve on the cold water (Blue) intake to the tank
( I have a short hose running from it to a bucket) -
I get a bit of air bubbles in my bucket then a steady stream
and the pressure falls on the Temp/Press. gauge to around 0 psi depending
on how long I hold open the fresh water intake valve? I think that's what it is...

When I release the one way directional check valve to let more
cold fresh water into the hot exit side of the tank -
the pressure gauge rises and I stop it when the gauge needle
gets to around 16psi.
The red bladder air tank...I try to keep at 12psi.
However, when I turn on the circulation pump and heater -
I hear some wicked gurgling....something's not right.
Sounds like there's still air in there somewhere.
Why don't they use a short length of some heavy glass tube so you
can see if there's bubbles or pockets of air in there?

There's a heavy red valve on the outgoing hot water line
over the red bladder air canister. Is this an "automatic air release valve"?
It has a very small bottle on top of it with a plastic screw cover
similar to the ones you see on bicycle tubes and tires.
I used a small air compressor to add some air to bring the canister up to 12psi.
The "auto-air" thing on top though is different...
I don't think there's an air valve on it like
there is under the bladder air canister.
It seems like it's just an upwards-pointing tube.

How is the best way to make sure the lines are filled and the air is purged?
It's not like I actually can open the hot water faucet because this is a closed system.
I don't want to burn out the heating elements!
Also, with a hydrometer, what should be the proper mixture ratio
and how can I add red anti-freeze to the system if needed?

I tried to make a drawing for you guys to see...attached also are some photos of this setup I'm working on!
You can enlarge them if needed I think by opening up the photos in another window...
Thank you very much for any help you can give me on this little project!
I'm all ears and open to suggestions!

-mark

[paul52446m]

Radiant floor heating setup gurgles?

Hi,
First I'd like to apologize if this is the wrong thread or forum.
I'm fairly new to this great website!
I am working on a maybe 7-10 year old 30 gal. hot water Lowboy heater
that is hooked up to a slab that covers roughly 350 square feet...
It's not sending heat up to the floor slab area.
My guess of 400 sq. ft is probably overstated -it's actually covering
less area as I haven't measured it.
It is filled with a mixture of Glycol (red anti-freeze)
and I'm having a bit of trouble trying to make sure the tank
and lines are filled with no air pockets.

Every time I open the valve on the cold water (Blue) intake to the tank
( I have a short hose running from it to a bucket) -
I get a bit of air bubbles in my bucket then a steady stream
and the pressure falls on the Temp/Press. gauge to around 0 psi depending
on how long I hold open the fresh water intake valve? I think that's what it is...

When I release the one way directional check valve to let more
cold fresh water into the hot exit side of the tank -
the pressure gauge rises and I stop it when the gauge needle
gets to around 16psi.
The red bladder air tank...I try to keep at 12psi.
However, when I turn on the circulation pump and heater -
I hear some wicked gurgling....something's not right.
Sounds like there's still air in there somewhere.
Why don't they use a short length of some heavy glass tube so you
can see if there's bubbles or pockets of air in there?

There's a heavy red valve on the outgoing hot water line
over the red bladder air canister. Is this an "automatic air release valve"?
It has a very small bottle on top of it with a plastic screw cover
similar to the ones you see on bicycle tubes and tires.
I used a small air compressor to add some air to bring the canister up to 12psi.
The "auto-air" thing on top though is different...
I don't think there's an air valve on it like
there is under the bladder air canister.
It seems like it's just an upwards-pointing tube.

How is the best way to make sure the lines are filled and the air is purged?
It's not like I actually can open the hot water faucet because this is a closed system.
I don't want to burn out the heating elements!
Also, with a hydrometer, what should be the proper mixture ratio
and how can I add red anti-freeze to the system if needed?

I tried to make a drawing for you guys to see...attached also are some photos of this setup I'm working on!
You can enlarge them if needed I think by opening up the photos in another window...
Thank you very much for any help you can give me on this little project!
I'm all ears and open to suggestions!

-mark

Hi Paul here. First let learn all the parts. Pic. two is your auto feed valve,so the stop blue handle valve just before the auto feed valve should be open all the time. This auto water feed valve is what is adjusted to maintain 12 LBS. pressure on the system.
The red tank is your expansion tank. This tank is suppose to be air charged to 12 LBS. To check this you have to take all the pressure off the system then you can check the pressure in the bottom of the tank in the valve core, add air if necessary .
On top of the expansion is a red air eliminator. This is to catch the air and take it up to the auto bleeder that is on top of the air eliminator.. Make sure the cap on the top of the auto bleeder is open at all times, and never put air into the system at this point.
Try running just the pump with out the heating elemits .
Send me more pic of the tank, valves and piping.
Like i said, run the pump no heat bleeder valve cap open, feed blue handle valve open and see what your pressure goes to and see if the air works out of the system, it might take a hr. Paul

[Stayouttadabunker]

Thanks Paul !!
Okay, yes...I have the blue handle fresh water open at all times.
Thanks for explaining how to maintain pressures.
I closed the water valve to charge the air tank canister to 12psi.
I actually had to let out about 2-1/2 LBS. or psi.

The cap on top of the air eliminator was on very tight - I removed it...
That may explain why the air in the tank and lines weren't getting out huh? LOL

The only way I can run the circulator pump without heat is to undo the lead wire to the Lowboy's thermostat on the tank near the top heater element.
Both the circulator pump and heater run off the same wires in the relay switch box with the two thermostats on top of it.

One thermostat sensor runs to the outside air temp and is for an "outdoor lockout" and is set for 48 degrees.

The other thermostat sensor is taped to the hot outlet pipe on top of the Lowboy and under the circulator pump - it's set at around 72 degrees.

I drained some Glycol out of the cold pipe spout into a bucket for about 10 seconds to get the pressure gauge down to around zero psi.
Now, I am running the pump while watching the pressure and
trying to maintain the pressure by gently lifting on the auto valve handle.

I've attached a couple more pictures of the Lowboys' safety relief valve
sticker and some company labels that are on the side of it.
Open them in a new window to view larger...>>>

[paul52446m]

Radiant floor heating setup gurgles?

Thanks Paul !!
Okay, yes...I have the blue handle fresh water open at all times.
Thanks for explaining how to maintain pressures.
I closed the water valve to charge the air tank canister to 12psi.
I actually had to let out about 2-1/2 LBS. or psi.

The cap on top of the air eliminator was on very tight - I removed it...
That may explain why the air in the tank and lines weren't getting out huh? LOL

The only way I can run the circulator pump without heat is to undo the lead wire to the Lowboy's thermostat on the tank near the top heater element.
Both the circulator pump and heater run off the same wires in the relay switch box with the two thermostats on top of it.

One thermostat sensor runs to the outside air temp and is for an "outdoor lockout" and is set for 48 degrees.

The other thermostat sensor is taped to the hot outlet pipe on top of the Lowboy and under the circulator pump - it's set at around 72 degrees.

I drained some Glycol out of the cold pipe spout into a bucket for about 10 seconds to get the pressure gauge down to around zero psi.
Now, I am running the pump while watching the pressure and
trying to maintain the pressure by gently lifting on the auto valve handle.

I've attached a couple more pictures of the Lowboys' safety relief valve
sticker and some company labels that are on the side of it.
Open them in a new window to view larger...>>>

That feed valve should feed water into the system without you having to left the handle. The handle is just for a fast fill. If you just have the pump running with feed valve open, it should feed the water into the system and when the system is full it should bring the pressure up to 12 Lbs on a cold fill, so let it go and tell me what it does. It will take a while. Is it letting air out of the auto bleeder. Do not drain out any water. Paul

[Stayouttadabunker]

When I bled some water out through the hose into my bucket, I reduced the pressure to zero LBS.
But when I filled the air tank canister to 12 LBS - the pressure gauge on top of the heater ALSO showed 12LBS.

Anyways, I disconnected the red 240VAC power wire to the top element thermostat - that effectively left the elements un-powered.
I ran the circulator pump for a few minutes and added fresh cold water to the system with the directional check valve to bring the pressure to exactly 12 LBS. Didn't take much really...just a touch of the lever.

I don't hear gurgling sounds anymore and as I put my ear onto the vertical pipes - I could hear the circulator rotor turning smoothly with a faint hum.
I have pretty bad hearing but I can't really tell if it's water running through or the pump itself.
It's not loud at all.
The pressure did not change at all and remained at a steady 12 LBS.
I figured it was ready for heat!

I turned off the outdoor lockout switch and went and turned the main power off to the panel.
I re-hooked the red 220VAC wire to the element thermostat and turned on the heater again.d the cold intake remained the same temp.

After a few minutes...I could feel the output pipe from the heater being slightly warmish thinking yeah! while the cold intake felt fairly cold.
Here's the problem now as we stand:
Even after 3 hours, the hot output pipe did not get any warmer and the pressure gauge also stayed at 12LBs.

I stuck a multimeter on the two heater elements.
I get 239 for the top element but zero volts on the bottom element.
I shut the power off...pulled off the red wires to both elements and got an ohm reading of about 13.1 ohms with both of them.
So they're okay?

Maybe the heater element thermostat on top of the top element isn't kicking on?
Shouldn't both elements be fully "ON" when initially starting up a cold water heater?
There are a small temp adjustment on each element but they are both set to 110 degrees.

Or do we still have some sort of air-lock in the system somewhere?

I'm attaching more pictures I photoshopped to help with and to help describe what is happening up here.
I am hitting the sack...I'm tired.
I'll watch tomorrow and see if you can add any tips and hints as to what to try next.
Again, thank you so very much for all your help thus far!

-Mark

[Stayouttadabunker]

More pictures of the thermostats...
and also of the air eliminator unit on top of the air tank.
Click on any photo in a new window to really enlarge!...>>>

[Stayouttadabunker]

The water heater panel box...>>>

[Stayouttadabunker]

Temperature and pressure gauge when powered up
and when powered off...
Best to open>>> in a new window to get the largest views...>>>

[paul52446m]

When I bled some water out through the hose into my bucket, I reduced the pressure to zero LBS.
But when I filled the air tank canister to 12 LBS - the pressure gauge on top of the heater ALSO showed 12LBS.

Anyways, I disconnected the red 240VAC power wire to the top element thermostat - that effectively left the elements un-powered.
I ran the circulator pump for a few minutes and added fresh cold water to the system with the directional check valve to bring the pressure to exactly 12 LBS. Didn't take much really...just a touch of the lever.

I don't hear gurgling sounds anymore and as I put my ear onto the vertical pipes - I could hear the circulator rotor turning smoothly with a faint hum.
I have pretty bad hearing but I can't really tell if it's water running through or the pump itself.
It's not loud at all.
The pressure did not change at all and remained at a steady 12 LBS.
I figured it was ready for heat!

I turned off the outdoor lockout switch and went and turned the main power off to the panel.
I re-hooked the red 220VAC wire to the element thermostat and turned on the heater again.d the cold intake remained the same temp.

After a few minutes...I could feel the output pipe from the heater being slightly warmish thinking yeah! while the cold intake felt fairly cold.
Here's the problem now as we stand:
Even after 3 hours, the hot output pipe did not get any warmer and the pressure gauge also stayed at 12LBs.

I stuck a multimeter on the two heater elements.
I get 239 for the top element but zero volts on the bottom element.
I shut the power off...pulled off the red wires to both elements and got an ohm reading of about 13.1 ohms with both of them.
So they're okay?

Maybe the heater element thermostat on top of the top element isn't kicking on?
Shouldn't both elements be fully "ON" when initially starting up a cold water heater?
There are a small temp adjustment on each element but they are both set to 110 degrees.

Or do we still have some sort of air-lock in the system somewhere?

I'm attaching more pictures I photoshopped to help with and to help describe what is happening up here.
I am hitting the sack...I'm tired.
I'll watch tomorrow and see if you can add any tips and hints as to what to try next.
Again, thank you so very much for all your help thus far!

-Mark

How are you filling the expansion tank to 12 LBS? Is there place in the bottom of the tank to put the air in? Do not try to take air out of that boiler drain that you have the hose tied to. That valve is to power purge the system. We could do the power purge, but we would lose all you antifreeze.
On a water heater like yours on a cold start only the upper element comes on, then when it get up to temp the power is transferred to the lower element. It would not hurt if the elements were set at 120 degrees. Paul

[HayZee518]

where are you in Malone? Maybe I could help you. I'm in Saint Regis Falls, 'bout a half hr from Malone. I got a clamp around ammeter and several meters [ digital and analog]

[Stayouttadabunker]

Haha! That would be great!
For you Hayzee, I attached a map with directions.
Just open them in another window to enlarge them.
I used the Google maps to get the pictures.
You can see on the map that I'm on Route 37 about
6 miles north of Malone going towards Ft. Covington, NY.

As you come nearer to the house, there's a church on the left hand side of the road and you will see a bunch of very tall pine trees just before my driveway on the right.
You will an older untreated cedar ranch style home with a light colored sandstone wall
between the house and the garage.

I will try to email you so we can try to meet at your convenience.
I don't have a hard line phone and just use a cellphone out here.

Paul,
At the very bottom of the red air tank is an air valve to where I attached a small, cheap air compressor to it and added about 12 LBS of air.
The cheap air pump I have doesn't have a very accurate gauge on it but it did the job as I saw the pressure also rise to 12 LBS on the water heater gauge.

I've purged at least 20 gallons of Glycol by now by that green
garden hose that I have attached to the cold heater tank inlet spout shutoff...lol sorry Paul!
My thinking was that would be like opening the hot water faucet when filling a regular heater tank to let the air out...
Now I gotta go buy some more anti-freeze I guess.
I have to get a hydrometer too...to see what mixture ratio is left in the lines.
I wonder what that ratio would be? 50/50 or less Glycol than that?
Or should I just use red RV anti-freeze coolant?

Finally, ( boy you guys have a lot of good questions! lol )
I did set those two heat adjusters on the elements to 120 degrees but the bottom element never came on - even after 4 hrs.
The hot pipe never got warmer than...uh...warm and it got kinda cold once it went past the air eliminator about 5 feet further down the line.
Warm water never reached the slab which would be about 25- 30 feet away on the above floor.
The inlet pipe on top got slightly lukewarm as well...the pipes never ever got hot to the touch and the bottom element never turned on.
I'm wondering if the elements so be changed out?
Maybe the element heat adjustment screw is malfunctioning?
I will turn them adjusters up to like 130 degrees each and see if that changes anything before I run out an buy some new ones.

[HayZee518]

is the circulator on the outlet side or inlet side of the heater. my reason for this, is the normal cold water inlet has a poly tube that goes to the bottom of the heater. once the upper element is satisfied it switches to the lower thermostat so as you draw hot water from the top, cold water goes to the bottom and turns on the lower element. as you know hot water stratifies to the top of a heater, so as the cold is heated it rises upward to the top of the bonnet. once you've exhausted the heater of hot water, the upper element turns on and shuts off the lower element. in the case of a oil burner heater the whole tank is heated at once, again the dip tube goes to the bottom and the stat is connected to the burner relay. the circulator if it is on the cold water inlet will force the cooled water to the bottom to turn on the lower element.

[Stayouttadabunker]

Thanks for the good question Hayzee,
The blue Grundfos? (Is that the name of it? Sounds like a German make or something...lol) circulation pump is placed on the outlet line just above the Lowboy.
By the way, the point where it exits the heater tank says..."HOT"
The other pipe going into the top of the heater says "COLD"
I'm kind of surprised that the freshwater cold inlet is attached just above the "HOT" outlet and Grundfos pump.
I attached pictures of it in my earlier posts...I also made a pretty good drawing to show everyone.
I re-attached it here with some photo shopping circles pointing out what's what...>>>

[paul52446m]

Radiant floor heating setup gurgles?

Thanks for the good question Hayzee,
The blue Grundfos? (Is that the name of it? Sounds like a German make or something...lol) circulation pump is placed on the outlet line just above the Lowboy.
By the way, the point where it exits the heater tank says..."HOT"
The other pipe going into the top of the heater says "COLD"
I'm kind of surprised that the freshwater cold inlet is attached just above the "HOT" outlet and Grundfos pump.
I attached pictures of it in my earlier posts...I also made a pretty good drawing to show everyone.
I re-attached it here with some photo shopping circles pointing out what's what...>>>

I already checked out the direction flow. One thing i can't see, is both valves in the pump flange in the open position?
Have you used the heating before? You said the out going line was getting a little warm. At 110 degrees going out that slab will eat up that temp and take
all night to feel any temp coming back Takes a long time to warm a slab. Try torn it up to 140, no higher. You did not answer my question from the last post. Can't help you if you don't answer questions. Paul

[Stayouttadabunker]

... Is it letting air out of the auto bleeder. ...

Thanks Paul,
I think I answered all the other questions in post #11 but I may have
missed this one from you post earlier in which I've quoted you from above?
If I did, I apologize as I am trying my best to give you guys as best detailed answers as I can.
Can you guys see my photos zoomed in?
I took the photos with a fairly high resolution camera.

Anyways, I'm not sure if it is indeed bleeding any air out of the air eliminator unit on top of the air canister.
I had removed the cap that was on the tube ( and left it off ) but I don't think there's any air valve in it?
I did put my finger on top of the outlet tube ( I think I mentioned that earlier) but I do not really feel anything coming out of it as the circulation pump is running.
Is there a way to check this particular unit for proper functioning?

This system has been running since 1986 but the Lowboy was replaced about 7 -8 years ago as I said in my 1st post.
I certainly do understand that it takes time to get the heat out to the slab ( at about 25-30 feet away from the Lowboy ) and get any warmer temp back on the return line to the heater tank, but the pipe in the immediate area just above the "HOT" outlet of the tank and around the pump, should be a lot warmer to the touch than it is no?
I do not believe the lukewarm water is reaching any further than about 10 -15 feet up the pipe. In fact, it feels cold at about 4 feet past the air eliminator unit.

I am still puzzled as to why the bottom element isn't turning on when the water inside the tank should be fairly cold.
with the wires off of the elements, what reading should I get ( in Ohms) to verify that they are ok?

I am running downstairs now to take some more photos of the Grundfos to see if that will help answer your question about the two valves.
BTW I didn't know the Grundfos pump HAD any valves...lol
I thought it just had a circulatory pump impeller inside?