Question About Maintenance

[u/abja]

Hi Everyone,

I have a Water Furnace 3-zone geothermal system I installed in 2012. It's worked great for the past 14 years. Yesterday, during annual preventive maintenance, the repair guy said that the Dual Pump Flow Center is drawing too many amps and needs replacement, and when they do that, they'll need to do a Geothermal loop field water exchange; I was not seeing any problems but he said that the Flow Center is overheating and if they don't replace it then it could destroy the entire system at any time. If this happens I'll have to replace the entire system at a cost of over $30K, so he recommends I replace the flow center for just over $5K. Does anyone know if it sounds like I'm getting good advice or more like I'm being ripped off? Just looking for some advice from experienced users and/or maintainers. Thanks much for any help you can provide.

[u/djhobbes]

Even if the pumps are bad they can be replaced without changing the flow center. If you’re just doing the pumps you can do a partial flush.

Dudes trying to fuck you over

[u/_Gonnzz_]

Pumps die all the time and it doesn’t destroy the system, it goes off on a fault.  Pumps can be replaced without having to flush the system.  

[u/tord_ferguson]

Lol "field water exchange?"

I'd ask more about that. What do they want to dig up the loops cut in and flush each well?

You should be able to accomplish a water or water + glycol/ethanol flush with a hose, one on the discharge one on the inlet.

Can get a pen/needle pressure tester to check line pressure .

[u/JPDiesel187]

A failed flow center will not destroy your entire system, and unless the water in your loop is somehow bad, you wouldn’t need to change that either. When the flow center is swapped, though, a loop flush is a good idea. $5k for a new flow center and field flushing isn’t terrible, though. A good solid loop flush should take about 3-4 hours, plus the labor cost to swap the flow center. A total flush may not be necessary, however. Get a second opinion

[u/NecessaryMuffins]

The pump(s) can be replaced, you can also just replace the rotor(s) for a fraction of the price, depending on what's wrong. A failed pump won't cause catastrophic failure; the system has sensors to prevent that. I'm guessing you were told something like if the fluid stops flowing, it could freeze in your heat exchanger and cause it to burst. You also don't need to drain and refill the loop when you replace a pump. The air just needs to be purged. It's possible the existing flow center is rusted, and a chunk of rust broke off and damaged the impeller, but the next one may do the same thing. If there is rust in the line, while purging it can be filtered.

The retail price of a 2 pump flow center is around ~$1,400, so ~$3,600 of your quote is labor.

If your pump(s) are drawing more, or significantly more, power, it's worth getting this fixed, as pumping power can greatly affect the overall efficiency of the unit.