Antifreeze Recommendations for Non Pressurized System

Need Help

Hi Everyone,

I am a GC, just built a new home for my family. Installed a WF 5 ton dual stage air unit. Enertech's design software said 420 vertical feet into granite would work, I have 2 wells at 230 each for a total of 460. System running all the time in winter. EWT is 30 degs , delta T is about 5-6 degs. Stage 1 kicks on, 21 mins later stage 2, 22 mins later W1 kicks on, 22 mins later W2 kicks on & runs for about 5 mins. Cycle runs for about 70 mins, off for about 5-6 mins then starts all over again. Dec power bill $ 770.00, 4400 kwh consumed. If I turn off breaker to elec heat what will happen? Any suggestions? Add a loop, can I add a horz. loop? System works fine in summer.

 

Hi,

sorry to hear about your problem. It sounds like the heat pump is undersized. May be the loop as well. If your EWT is 30° you are not out of loop capacity yet, but you are clearly about out of heat pump capacity.

If you shut off the aux heat, the unit will run in 2nd stage longer, maybe continuously with out ever reaching the set point on the tstat.

It won't hurt the heat pump and it will save you some money, but your house might not be as warm as you like.

Where do you live?

On a side note:

I didn't know that Enertech had a design program, what is it called and where did you get it?

Hope this helps

 

In a standard WF (Envision) installation, the air-handler fan
is powered from the same breaker as the electric heat --
that's so you'll still have air flow if the heat pump fails and
the compressor breaker trips.

I believe there's a DIP-switch on the processor board that
disables "emergency heat" except in the case of a true
emergency (e.g., compressor failure).

Looby

 

That's exactly where i am at using about 130KwH/day! I also have a WF 5 ton, only difference is 3000ft horizontal looping per the recommendation of EN of 600ft/ton.

I have done the above suggestion and flipped the dip switch on the board so as to not use aux, and yet my electricity consumption is still cranking the same!

So interesting - same unit, different looping - so could one do an "elminate the looping" from the equasion as we have similar results yet totally different looping and say that our issue is may with this specific model???

Out of interest, can you tell me what model thermostat from WF you are using??

 

Di2009,

I have a Geocomfort GT064 HP, it is made by WF, it is a 5 ton unit. RobertShaw 300-202 T stat. The HP is controled by an EWC EZC4 control board. I called EWC and spoke to rep who designed board, he had me check board, & I found out that the factory default setting was set up to call each stage of heating every 21 mins. That is because it is shipped for single stage heating & cooling. It was 0 degs at 8 AM, he told me to turn off the staging call. I usually keep T stats at 68 degs, no set backs. The HP now was not calling for aux heat at a predetermined time. First stage aux heat came on a few times & ran for awhile. I have since set my t stat for set back at 66 degs. I am only one at home now. HP is working great, maintaining 66 degs on 1st stage HP only for the last 4 hrs, it is 12 degs out right now. I am considering disabling the aux heat using the dip swithes. Hope this helps. Thanks to all who replied.

 

Question - as i can't access my board to see what's it's set up as, do you think I could achieve similar results to your for now by changing the "Differential" on my thermostat to 1 degree diff between Stg 1, 2 and aux calls?

 

Di2009,

I am not sure, I got advice from a number of different sources.

 

t stats

This is one of the most common install errors that I see. Todays t stats are so programable that the t stat itself can create the afore mentioned condition by doing things with the stages and auxillary heat that you are not aware of untill your first horrific electric bill.

Another common error I see is with climatemaster units being set up from the factory for open loop, and the installer not cutting the jumper when it is installed as a closed loop.

Hope this helps
Eric

 

Hi everyone. I'm new to the forum. I'm looking for some recommendations for my system.

I have a 3 ton heat pump that has been running trouble free now for 3 years, but just recently I’ve been having an issue with the coil freezing up. The system is non pressurized. It's a horizontal system consisting of three trenches w/500’ of 3/4” pipe per loop. The pipe in each trench is layered at 6' and 4'. I’m using a single 240 volt 2A B&G circulator to move the water. I have never had any antifreeze in the system and have never had any problems with it until this winter.

I live in North Carolina. This year we have had more snow than we have had in a long time. This is certainly the most we’ve had since I installed this system. I’m not sure what effect snow has on ground water temperatures, but I suspect it may be the cause of my problems. We have had colder winters, but not nearly the snow. Yesterday I measured the loop water temp at 50 degrees. This measurement was taken after the system had been shut off for about 3 hours. Then I started the system up and let it run for 15 minutes. The entering temp was around 40 degrees. The exit temp was around 34 degrees. I let the system run and within 15 minutes it was frozen.

In the previous winters, the coldest exit temp I remember measuring was around 38 degrees.

I would like some advice on what type of antifreeze to add to the system. Glycol, methanol, ethanol? Where can a diy’er buy it? How much should I need? Should I worry about fumes getting into the house because of the non pressurized system (everything is in the basement)?

I'm also open to hear any other suggestions on what my problem might be.

Thanks for any input.

 

Antifreeze is typically either:
- ethanol
- methanol
- propylene glycol

Grab methanol at an auto supplier and pg at a plumbing supplier.

The latter is probably the safest for someone to handle if that makes a difference. Freeze protect to code or to 9F below your lowest EWT. You'll have to do some fancy math to determine how much to add - and/or buy a hydrometer that measures specific gravity in the range you need.

Is your system a true non-pressurized system? Or just a system in which you don't have it pressurized?

A lot can explain what is going on with your system but we need to narrow down a few things. The snow shouldn't be an issue.

 

This may be a good time to ask. Can someone please explain a pressurized vs non-pressurized system (other than the obvious statement that one system has pressure and the other does not.)

 

Pressurized is a closed system kept under pressure.

Non-pressurized is a system open to atmospheric pressure. The pumps packs used for this have a standing column of water that allow the air to rise to the top.

The pressurized system that loses pressure (or was never pressurized) does not operate the same way as the latter; thus, my question.

 

I have a non pressurized, horizontal system about your size in N. Arkansas. My water temps are lower than they have ever been (15yrs.). I assume you're talking about ice forming on the outside of the coil and not inside. I used prop. glycol as I thought the ethanol would evaporate over time. I have not had any trouble with it. I checked it pretty often for the first few years but after no change in PH or SG, I stopped worrying about it. Mine recovered some (41 EWT) but now it's headed down again after days of teen and lower temps. and 20 mph winds. This is coldest winter here since the early 80's and most snow, too.

 

Yes, your symptoms sound very much like a lack of antifreeze.
Methanol and propylene glycol are you common options.
There are plus and minuses for both. We use methanol now,
- price
- degree of freeze protect
-thermal conductivity
-viscosity

are all in favor. Some people are intimidated by the methanol and the fact that it is flammable and explosive. Mix it outside in the absence of any potential for sparks or open flames to a 50:50 concentration before you bring it into the building and add it to the system.

 

Thanks for all the info so far.

Yes, the system is truly non-pressurized. It uses a Hydro-Temp Auto Purge, which to me is a fancy term for a reservoir, mounted at the highest point in the system, that holds make-up water for the loop. The reservoir has a top on it, but it is basically to keep debris out of the water. It is not air-tight. The water level fluctuates with the temperature of the loop water. Right now the water is at about 20% full. Does anyone think adding a few gallons would make any difference?

As for the anitfreeze, right now I'm leaning toward methenol, but I do have one big concern about it. With my system being open to the atmosphere, will the methenol evaporate or "off-gas" into the house? I don't like the idea of the methanol fumes in the house. Is my concern valid? The actual handling of the methanol itself does not really bother me.

As for glycol, I don't like the fact that it changes the viscosity of the loop water. In my previous post I said I had a 2 amp circulator pump, but I was wrong. I just checked it and its actually a 1.1 amp B & G. Is that enough of a pump?

thanks again

 

You need to be very care full here. If ice forms inside of the heat pump. It can burst the coax heat exchanger.

This will be a very costly $$$$$ repair.

 

By the way, ice will form first in the coax, since this is the coldest part of the loop.

 

I tried to post a reply earlier but I don't see it on the board. Anyway, Yes my system is truly non-pressurized. It uses a Hydro-Temp Auto-Purge set up. Basically a reservoir at the highest point in the system that holds about 5 gallons of make-up water for the sytem. The water level in the reservoir fluctuates with the temperature of the loop water. The reservoir has a lid on it to keep out debris, but it is not air-tight. So the system is exposed to the atmosphere. It has worked fine now for 3 years.

As for anitfreeze, I like all the benefits of methanol, but I have one major concern. With a loop system like mine that is open to the atmosphere, will the methanol evaporate or "off-gas" out of the system and into the house? I don't like the idea of methanol fumes in the house. Is this a valid concern? Does someone here have a definitive answer on this?

I don't like the viscosity effects of glycol based antifreeze. In my first post I stated that I have a 2A circulator pump, but I was mistaken. I just checked it and it is a 1.1A B&G pump. Is that enought of a pump if I choose to go with glycol?

thanks again

 

Yes methanol will volatilize out of solution relatively quickly. I wouldn't consider it a health or safety risk so much as an operational issue.

I'm a little too lazy, with the Olympics on, to look up your pump curve, so I can't comment on the PG viscosity effects on your system.

 

Don't worry, the only time I can really smell it is if you are right above the opening of the reservoir tank.