Repeated Flow Lockouts On Hydron Module - 7ish Year old system first time ever having an Issue.

I just want to preface this with that I very much appreciate any and all assistance you can offer me at this point. I realize it's a holiday time for most of you so anything you can offer as far as ideas or insight into the situation is greatly greatly appreciated.

History: My father was an incredibly talented guy who was a CPA that prepared a particular type of report that only required him to work 3-7 days a month. Back in 2004 he decided that he wanted to put in Geothermal heating in the house. We live in NJ and Dad wanted to install the unit himself but retain the full manufactures warranty.

He decided on a Hydron Module unit and completed all training, tests and received appropriate certifications so he could keep the full warranty. The installation was done around 2006 after extensive planning and work with the township. We have literally never had any issues with the system... ever. Until now.

Here is the rub, my father passed away September 5th and of his two son's I'm the only one that lives in NJ and is near enough to help. I'm good with basic electrical (running circuits, through hole soldering, moving outlets from one circuit to another) plumbing (copper and cpvc but no pex experience and only pvc for dirty water) and I've got a good analytical mind for working through problems.

Specifics: We live in NJ. The pump is the Horizontal Hydron Module H050 (Horizontal 5 ton unit). The flow center is a non-pressurized QT flow center (2-230QFC, 2 pump, Grundfos 26-99). The closed slinky loop field is at 2 depths 6ft and 9ft with 3 coils at each. 20% solution glycol and water good for down to 15F. 100% Geothermal system.

Initial Problem:About a week ago the unit slipped into a fault mode and kicked over to Aux Heat (which is not set up and just causes air to circulate through a cold system dropping the temp of the house like a stone.

I was advised to check the flow center for proper functionality, however one of the pumps was dead. I obtained two brand new replacement pumps (identical model grundfos) and had no issues putting them in, I then did the manual process to push liquid through the pumps so they wouldn't overheat. I reset the unit and everything kicked back on and happily ran for about 8 hours.

I had gone home by then get a call that it happened again.

I restarted the unit and noted that when the screws were loosened from the pumps on the flow center only the bottom pump makes a sucking noise. Unsure of if this was normal function I waited till T-Stat signaled an off, then turned off heat at T-stat then waited 15 minutes then proceeded to switch the pumps and observed the same functioning and determined that must be normal operation. I then switched in the working old pump in place of one of the new ones, and the same issues are still being seen.

Assumption: In my testing and pump install/switching I introduced significant air into the loops.
Assumed Solution: Flush the loops in the manner that they would have been filled which is one loop at a time through the flow center.
Outcome: The flow center level did not drop significantly leading me to believe that there is minimal air in the lines. However after an hour of running the system flow sensor tripped which was in the middle of the final line purging. I turned off the T-stat, waited 30 minutes, reset the system, waited another 30 minutes and then started the unit back up at the T-stat still set up to flush that final line. The system ran without issue for 20 minutes while I re-purged the first coil after the last, still with no siginificant air release.

I do not have, or cannot find a flowmeter tool I realize this is an important piece of equipment but if we could please work around this as best as possible at the moment. I also do not have a flush cart.

I do have a Pressure Gauge with Needle which, as I understand it, allows me to measure the pressure drop.

Next Steps: I plan to use an AC Clamp to measure the current flowing to each motor. If the readings are not in line with the label on the motor I will replace that motor accordingly with the new motor and re-measure.

There is no "test" jumper that I can see on the lockout board of the Hydron unit so I only have the open flow led to go from to troubleshoot this issue. I'll be calling a professional help line Monday morning but seeing as it's the 24th I don't anticipate it actually being open.

Currently two of those oil filled radiators are doing a decent job of keeping mom comfortable but the climate has been temperate so far....

Thank you all for you time. I look forward to your input.
Kind Regards,
Bryce

 

Bryce:

You can use your "pete port" pressure gauge to determine flow through the machine. There should be a chart in the I/O manual to convert delta P to gpm. It helps to lube the "needle" before insertion into the "port".

I have never worked on a Hydron Module machine, but heat transfer is heat transfer. The manufacturers build in the lock out systems to protect the expensive parts of a system. The sensors that feed the logic in the control board can go bad. You need to isolate the sensor that is shutting the system down and test it. If the sensor is a pressure switch and you have an electric multi-meter built into your amp, (clamp-on) meter you can test if the switch is open or closed by reading the ohms through the switch.

If the board is looking at temperature the ohm meter can tell you what the board is seeing. Thermisters do go bad as do pressure switches.

Now that you know what you can see with the tools that you have so far lets talk about flow.

You know that you lost a pump and the unit went down. You replaced both pumps and one mad a noise. It should not make noise. My guess is you did not get a good seal on the O-ring to the noisy pump and what you heard was the pump sucking air.

Air in a closed loop system can stop water flow better than a ball valve. In an open non-pressurized flow center the air is supposed to self-bleed, but that is not always the case. If you hear flow you usually have air. It does not take much air to stop flow.

You have the ability to pump ope loop at a time, Dad did well with his piping. I get the concept but not having boots on the ground in the mechanical room I can not tell if you got the air out. My guess is no.

If you could add a few pictures of the machine, flow center and near machine piping it would help. There are ways to "trick" the air out of a system.

I do not think frozen Moms are a good thing. You might look at our lists of local talent here on the BB for someone in NJ.

Good luck and Merry Christmas,

Mark

 

Hey Mark! Thanks for the response, especially on the holidays! I'll add in some information.

I'll look to see if I can find the service manual for the conversion. What sort of lubrication would go with this? I'm loathe to use petroleum jelly because of the propensity to degrade rubber/latex but maybe just some good old water would be a good option?

I do need to come up with some clips for my multi meter. That'll really help make things easier. I tested bypassing the flow switch by just connecting the lines and the system still trips off. A bad thermistor makes perfect sense, the Temp in was around 54 at the time and the temp out at the time was 49. If a thermistor is bad the flow switch will trip regardless of the actual temp, and regardless of if the actual flow switch is working or bypassed.

The sucking sound was only heard when I unscrewed the large screw on the pump itself that allows you to access the drive shaft to push water into the system for lubrication. The pumps make no noise when the screws are properly installed.

I will do my best to get some pictures for you. Each loop comes into the home in the basement and has its own ball valve. I'm pretty certain there isn't air in the lines as the water level in the flow center does not change when running any one loop versus running all six, but I'm sure open to the possibility that I'm misinterpreting that.
http://www.pics.and-a-half.com/geothermalheadersbasement.jpg

Very much agreed! Thankfully I've got 2 of those oil filled electric fin radiators in the home and they're doing a good job of keeping it a toasty 69 degrees. Thanks so much for all the information and ideas.

Have a very Merry Christmas!
Kind Regards,
Bryce

 

I agree it sounds like a significant amount of air causing pump to quit on overload. Did you use 3 way valves to isolate pump from loop field while performing service.
Information available is a little scant to really diagnose.
Merry Christmas Mark and others.
j

 

I will let Joe tell you what he uses for lube. I use Simple Green or Prell.

While you are looking at the I/O manual look for the wiring print. It should show if you have a thermister or a pressure switch. There should be a print on the cover panel too.

Off to find bibs, parka, and snowmobubble boots.

Living on the South shore of lake Erie I was taught as a child to keep a good compass in your fishing tackle box. If needed, believe it. I have not been to Ontario by boat yet. The same holds for test equipment. Get the good tools and become a genius among your peers. Most of the best hands on techs I know are motor heads or where motor heads. There is something about internal combustion and HVAC, I guess.

Most thermisters are Western Digital and are easy to check with an ohm meter and a good thermometer.

My help desk phone is 440.223.0840, if no one answers I am dead or asleep.

Mark

 

Hey There Joe,
The pumps were isolated with 2 ball valves (one just below and one just above). I can verify that it's not air at this point I'll detal that a few lines down where I answer Mark's question on the switch type. Thanks for the advice I am sure I will need to revisit air in the lines after I get the unit back up.

It is just a simple open/close pressure switch. Monday I did get to talk to my tech support contact and he had me bypass the flow switch (jumper). However even with that the system would instantly light the flow led on the lockout board after a power off reset. Then today we got Enertech support on the phone and they agreed that it must be something wrong with the main board. I should have that come Friday.

Sounds like a good day to enjoy being bundled up outside in the fresh air!
I'm doing my best to make sure that I'm learning as much as I can. I find all of this really fascinating, I just wish it was my own house!


Again, many thanks to both you and Joe for all your help. I'll keep this thread updated with how this gets along.

-Bryce

 

When you get Mom's system fixed you can branch out to most of NJ from what I see.

One needs to know how a system works before trying to find out why it suddenly does not work. Your Dad, did his home work and I am sure you are just looking past a point of operation he would see as a reason for a fault lock out.

My skill set has taken me 60 plus years to acquire, including the time I drove a nail into my bike tire so Grandpa would take me and it to the Sohio station to get it fixed. I wanted to know how to fix it. You have that thirst for knowledge, it becomes you.

Keep us up to date on this situation as many do not do that and we never know it a system got fixed.

Warm regards,

Mark

 

Hey all,

I've got the system back to running when the call for heat comes through the T-Stat and it's pretty easy to hear what seems to me, a significant amount of air in the last three lines. I keep trying to think of a way to flush the air out but if the flow center isn't doing it I'm at a loss.

I managed to get a pressure drop measured and it was about 3psi measured right at the hydron unit. I can't figure out how to get that to tell me something meaningful.

Here is a picture of the headers as they enter the basement:


Here is a picture of the flow center:


Here are the valves at the Hydron Unit. This is where I measured the pressure drop and take the EWT and LWT.


These are all of the valves that there are with the system. There is no valved connection between the in and out of the field which I've seen in quite a few diagrams.

When I'm looking at the loop headers all the way to the right there are threaded ends where I could (in theory) just hook a gardenhose right on and add water to the system. The last three valves at the top row of headers make a "pshhh" aerated water noise if you close them slowly and if you close them quickly they get that "thunk" sound.

I can't figure out a way to get that air to get the heck out of the system, and I certainly don't want to go willy nilly adding water to one side or another without actually knowing what I'm doing.

Any thoughts at this point? I'm currently just letting it all sink in and trying to follow the fluid and figure out what would work to either turn the big bubbles into a mobile foam or some way to get the pump to push them out.

Thanks again for all the help. I know it must be a bit painful to try and decode what I'm saying and give some sort of assistance.

Kind Regards,
Bryce


EDIT: I just thought, I have the wiring diagram so I can pull all the wires to the master contactor except for the flow center. Then depress the contactor and let that just run the pumps on the flow center. I can have it pull one loop at a time which might give it enough strength to remove the air. And I don't have to worry about the actual flow rate because the compressor/heat exchange isn't actually running or happening despite the fluid going through the hydron unit. Thoughts?

 

If that is a push pull set of 26-99s you have lots of pump. The solution in in your first picture.

With the ability to flush the loops one at a time as you tried, but failed at, you need to keep the pumps running without the heat pump. I am sure the pumps are powered through the heat pump wiring panel and are attached to lugs on a board.

Can you read wiring diagrams?

Mark

 

I can read them pretty well. To me it looks like the easiest and most straight forward way is to bring 1 & 2 into the headers where 3 and 4 currently are.


Here is the part of the wiring diagram that I'm working from (there's no de-superheater installed thus I cut out that part of the diagram.)
The section I labled 1 is the 230v out to the pumps. The two "reds" accross from it connect into the master contactor which handles the power coming in from what I labled 2 which is is from the electical panel.

 

Or you can remove the wires going to the compressor at the terminal above the blue bar. then you do not need to move things around and can control the pumps from the thermostat.

Turn the line voltage to the unit off. Tape or wirenut the removed wiring.

Mark

 

Hmm ok, that makes sense to me. I can remove Red, Yellow and black wires going to the compressor and just go to the thermostat and call for heat. Wouldn't that still kick the blower into operation though? So I'd have to also pull out the ECM motor connection on the main board as well?

 

I get used to doing water to water. Check at the compressor for a uni-plug and skip messing with the contactor. I do not think the blower will bother you as you may be at this awhile, but it might piss Mom off. Yes, there should be a molex type plug between the ECM and the board. Or go back to plan A. What ever you feel comfortable doing.

Just watch out for random electrons.

440.223.0840
Mark

 

That sounds great. I went with pulling the compressor power out of the top of the contactor, then pulled the entire ECM plug from the main board. Flipped the breaker back on and now just a 5 minute lockout delay before I turn it on at the T-stat.

Now as far as flushing the loops. Do you have any tips/tricks on that? Should I run the whole system open for 24 hours or should I run each loop for an hour or 2? I know I'm going to need to keep checking on the water level in the flow center but is there anything else to watch out for?

Thanks so much for all your help. Everything we're doing makes perfect sense to me and I'm incredibly appreciative for your help.

All the best,
Bryce

 

Brice:

I would not have given you the ability to electrocute yourself if I did not think you could fix this safely.

Here comes your purging tricks:

Dan H at heating help.com says you need to think like water. He has been telling me that for years and years, he has a great site. "Water is lazy it takes the path of least resistance.".

Now that you know that this should go well.

Pump one loop at a time. For a while. While pumping the loop slam shut the ball valve on the return side of the loop. While doing that watch the level in your flow center if it bobs up and down with the valve closed you still have air.

If you can not hit the loop valve use the ball valve on the flow center.

Air can stop flow like a valve so after testing and bobbing try varying the flow through the loop. Slamming the valve on the return can help the air move. I have also had good luck slowly opening and closing the valve.

I do not know if your pumps are push/pull, paralleled or series.

This should get you started. DO NOT let the level in the flow center expose the intake to air, or it is go to jail, do not pass go.

Mark

 

Bryce, I'm Mark's wife. He would like your phone # if you need to be talked through this. You can reply to scustis@centurytel.net.

Warm Regards

 

Oh heavens, I didn't have any fears of electrocuting myself! I'm far more paranoid about damaging any of the equipment! Dad did a great job of teaching me how to work with (and respect) household voltages.

 

NP

That's what Human beans do for each other.

If this is working as described I would get a beer and hug the flow center.

No froth and no bounce means you are done. Go to the next loop. Lather, rinse, repeat.

M

 

I certainly think you've gone above and beyond! I'll be checking on the flow center every so often making sure the levels are ok and getting the air out of those lines.

Thanks again!
Bryce

 

Ok so I'm poking around with these valves and I'm having some success getting the air out. How much "thump" and general noise should I hear from the valves. My assumption is that since it's a fluid system there should be minimal noise on open/close of valves.

I'm doing my best with trying to coax air out with some open/close of the valves on the headers.

Would playing with any of the valves on the flow center be advantageous/dangerous?

Is there an amount of air I should accept as "reasonable"

Would leaving the whole system to run be successful?

I'm certainly willing to accept any/all more specific tips/tricks here. I'll definitely be leaving it to run all night which I'm sure will help.

All The best,
Bryce