Water source heat pump

We do not have too many water source heat pump systems here, but the ones I’ve seen use a closed system with looped pipe or a vertical well and get their heat from surrounding ground. The system I looked at today used the potable chlorinated water system (county rural water provided for ranch use) and then dumped the used water into a stream. Other than being a waste of water, I’m concerned that the chlorine and fluoride will eventually damage the pipes in the heat pump. Any thoughts?

I bought a used water cooled AC which I used for years and it just wouldn’t die. It used chlorinated city water. The person sold it because he was paying for water and water rates tripled in his area.

I concur. Water cooled. Plus 20 years on average. Seen >30 year old models.
Likely refrigerant has been boosted.

Chlorinated water can effect plumbing pipes and fittings. For example high levels of calcium in water leads to a calcification build-up in pipes and fittings and chlorine introduced into the water supply has been known to accelerate the corrosive action of both metal and plastic plumbing fixtures.

Heat is the answer, Marcel.
Air cooled. Ambient temp fluctuates. Seasonal. Average ><20 - 100 F…
Municipal Potable water temp. Seasonal. Average >< 58 - 70F.

As a general rule of thumb, a minimum flow of about 2.5 to 3 gpm for every 12,000 Btu per hour (ton) of heating and cooling will be needed (though some units specify flows as low as 1.5 gpm/ton for open-loop systems and 3 gpm/ton for closed-loop systems).
https://wellowner.org/geothermal-heat-pumps/q-how-much-water-does-an-open-loop-geothermal-heat-pump-system-require/

Water source heat pumps all have the same issue. They are subject to the affects of the water you use (which is the biggest problem for this system).

The type of water system you use is based upon what is available on site. You can’t use a closed loop in the yard, if you don’t have a yard. You don’t go vertical if you have to drill through 300 ft. of solid rock. And unlike places such as California where you can’t trap water from your roof, Using and dumping domestic water is not a waste because your putting the water back where it came from. If it is cost effective, use it.

The water system must be properly designed to handle what you put through it. Wells are more problematic than treated city water in almost every case. If domestic water is excessively high in any adverse substance it must be treated on a case by case basis.

I have worked on well systems in New England that had high mineral content which would restrict the flow in the condenser. The system detected the reduced flow and reversed cycle with no water flow through the condenser which froze, removing the scale on the inside of the pipes. It sounded like a popcorn machine!

No system uses DI water because of expense. You use what is available and redesign the system as required.

As a HI you are not qualified (lack of proper tools) to assess if the water used is sufficient for a particular system, but hope this provides a little insight of how we handle this. Without testing your water, I would venture to say that domestic water is safer than unprocessed water in the system.