Hi, I have a 6 year old Envision WaterFurnce model NDV049A111CBR. Closed loop system with long runs in ditch, not drilled. Dual pumps are 230 volt. Current (normal) draw is about 1.2 amps each. Both fuses in the 230v source are 10 amps each. Both fuses blew the 6th of Jan. No a good sign so I called the service tech (Furnace still in warranty). I thought there was an extremely good chance one of the pumps was shorted or just locked up. The service tech replaced both fuses and the pumps started and ran OK. I was surprise but not convinced anything was fixed. This past Sunday, both fuses blew again. The tech had installed 10 amp glass fuses instead of the original ceramic, I don't have reason to believe that's why they blew again but it was sure easy to tell they were blown without anything more than a look. Both were very well burnt inside the glass. I bought some 10 amp ceramics after the Jan problem so I installed them last night and all is well again. I expect need shut down to occur even sooner. I apologize if my explanation is too long, just wonder if anyone with experience see's this as a trend and have an idea of what the real problem is? FYI, The DHW pump was and had been turned off before the fuses blew this second time. Is this not surely a sign of a bad pump/s? Thanks for any help!
Thanks Chris. I just wish it would short and stay that way. Then my dealer would have to replace the shorted pump. One of the pumps may be locking up some times - not a permanent problem yet but obviously it will get worse. Again, thank you for the reply!
Mike do you know what type or model number of pumps you have? I remember a pro here talking about seeing more failures in "wet rotor" type pumps as small debris from the loop gets in there and causes issues.
Yes, The Geolink Flo- Center itself is type FC2-FPT (dated Aug,2008) and both pumps are Grundfas PN 52722366 P1. I could not find that exact part number anywhere on the web including the Grundfas site. Those are definitely the numbers on each of the pumps I have on my system. For now it as a temp. problem but it's sure not gonna get better on it's own. It would be great to know (at least) if it's a known problem on particular pumps. Thank you for your help! Mike
Had this reoccurring problem on one system. Pumps were mounted with elec boxes on bottom. Condensation getting into electrical connections? Rotated pumps so boxes were on top and problem dissappeared....
Interesting. My pumps are also mounted that way. They are above the floor though in a heated room next to the geo furnace. I would guess too? that even a small leak in a pump seal would let a bit of loop water to accumulate in one of these boxes?
Mike: I would suspect condensation not a leak. The pumps are on the cold side of the unit in heating. Go find your allen wrench set and turn the motors at least 90* or better yet 180*. Read your I/O on the flow first. You do not want to need a re-purge. Mark
Thank you for the reply Mark, I haven't looked at it yet but will. I do have a related question. The manual says to refer to the Flow Center installation manual (IM1961) and Flush cart manual (WFS302). Does anyone know a link where I can download those? I tried Google and it just refers me back to the Geo Manual.
This one covers your FC2-FPT flow center. Not sure if the vintage is right. http://www.waterfurnace.com/literature/geolink/IM1547EW.pdf
Thank you! for the pdf. I just wanted some basic info and this is close enough if not the right vintage.
One other note. The problem pump was a grundfoss with the spring clip style wire connections. Was wiggling wires at that pump when I got it to blow fuses again so changed it out to a pump with wire nut connections at the same time both were rotated. (Two pump flow center)
I still need to check on the wire /short problem. I appreciate all the suggestions from everyone! All good things to look for!
Mike I noticed you mentioned your loops are buried in a ditch. Do you know if this reduced the length of trench needed as I assume the ditch is wet?
Actually I used the term Ditch sort of loosely just to I.D. it as not a series of wells. It was installed trench that was dug by the installers and refilled with thedirt removed. We live on a 4 acre plot, no trees (at the time) so plenty of room. I did check the input loop temp when the fuses blew and temp was 36 F. Likely OK? considering we've had a very cold Feb here in central Indiana. Pumps are still running (borrowed time I'm sure). I need to check this out and believe me I'm not at all lazy. - Just recovering from eye surgery for double vision. I appreciate all help very much and will absolutely reply if I find the problem! Thanks to all again! Mike
