Converting open loop to closed loop - what should I worry about
Last Post 15 Nov 2022 12:19 AM by sailawayrb. 5 Replies.
Author Messages
mssusr9501User is Offline
New Member
New Member
Send Private Message
Posts:2

--
16 Oct 2022 11:30 PM
How do I make sure a closed loop will meet the (primarily) heating requirements for the home?

Currently running a Bard 3 ton 3GV38S2AANwith an open loop from well, discharging to nearby river.
Unit appears to have been installed in 2015 and has two stages if I understand correctly
In last few years PFAS contamination of ground water has been discovered.
Now private wells are being condemned, city water being run.
Need to look at converting to closed loop.

I reviewed the "what to consider before buying" list but not sure if all factors apply to conversion.
We are in western Michigan  a few miles north of Grand Rapids.

Home is about 1800SF with walkout finished basement adding another 1500 SF.
Walls and roof deck insulated with spray foam, windows are Andersen 400 series and only a couple years old.

As I understand it, changing from open to closed loop has a built in efficiency loss.
The incoming fluid temps won't be as stable with closed loop.
Flow will also need to be higher, Bard suggests current setup is probably running 6 GPM, closed loop will need 9 GPM.

Have a quote to drill horizontal loops (angled down actually), a bunch of money.
Our property is heavily wooded and trenching would be challenging.
Still waiting for HVAC guy to respond with info on heat loads, alternatives and answers to questions such as "Is current Bard sized appropriately".

House is all electric, no gas on the property.
Options are limited.

newbostonconstUser is Offline
Advanced Member
Advanced Member
Send Private Message
Posts:735

--
17 Oct 2022 11:29 AM
PFAS thing is the new global warming....I am near ann arbor and that is all they talk about.

I have had two houses, one open loop and one closed loop....didn't see much in efficiency difference but for your setup I would measure your temp drop across the unit now for reference and then put in a rightsized variable pump and change the speed to target similar temp drop values. In my experience most aim for a 10 degree temp difference.

You are looking at a big expense....can you keep the well for heating and city water for drinking(I know they don't like this but ask them for formal paperwork as to why not - they are liers in normal conversation)....has your property tested positive?
"Never argue with an idiot. They will only bring you down to their level and beat you with experience." George Carlins
mssusr9501User is Offline
New Member
New Member
Send Private Message
Posts:2

--
17 Oct 2022 10:36 PM
Yeah, I've been seeing the articles about AA PFAS.
It sounds as though wells will be condemned for all purposes once city water is available.
Even if they let us keep the well for geothermal, they won't approve permits for new wells when the old well fails.
Our choice at the moment is 20K+ to convert and run loops or 20K+ to bring gas to the house.
Been a real cluster for the last couple of years waiting for bureaucracy to figure out what they are going to do.
newbostonconstUser is Offline
Advanced Member
Advanced Member
Send Private Message
Posts:735

--
18 Oct 2022 05:49 PM
Have you ever thought of doing an air source heat pump? or mini splits...?

They have come a long way on efficiency and quality....plus with your savings you could put some solar up to offset electrical costs.

Do you have a wood burner, it would help on the cold days....
"Never argue with an idiot. They will only bring you down to their level and beat you with experience." George Carlins
newbostonconstUser is Offline
Advanced Member
Advanced Member
Send Private Message
Posts:735

--
18 Oct 2022 05:49 PM
duplicate...
"Never argue with an idiot. They will only bring you down to their level and beat you with experience." George Carlins
sailawayrbUser is Offline
Veteran Member
Veteran Member
Send Private Message
Posts:2270
Avatar

--
15 Nov 2022 12:19 AM
PFAS appears to be becoming more problematic around the country. Here's the PFAS "forever chemical" map:

Interactive PFAS Map

Thankfully, we don't have a PFAS problem in Southern Oregon yet, but we do have other well water quality issues like Arsenic.

We had a neighbor die from multiple cancers several years ago...likely because the family just drank their well water without removing the Arsenic. We primarily use our creek water as our primary source of our domestic water (and for our irrigation and fire suppression water), which has tested pristine with the only potential risk being biological which we address with multiple sources of UV light treatment. Nevertheless, we did recently construct a well water filtration pump house to remove high levels of Arsenic, Boron, Chloride and Sodium and enable us to use this well water as a backup water source should it be needed. Here's some info on how this was accomplished which I hope others may find helpful and useful:

Well Water Arsenic Removal
Borst Engineering & Construction LLC - Competence, Integrity and Professionalism are integral to all that we do!


---
Active Forums 4.1