Replacement E3D Thermistor

Hello all,

I have a Taz5 with a Dual V3 head on it and recently had to replace the thermistor. I used a E3D thermistor (E-SEMITEC-50-MOLEX) that is available on Amazon. It seem to be the same encapsulated unit (Semitec 104GT) that is originally on the head, and worked well for a few prints. Then the temp reading dropped by around 8 deg when idle and cool as compared to the other head (and bed) and who knows how much lower when hot. This started causing issues with prints, so I figured I got a bad one and replaced it again. Same issue. Is there something wrong with these compared to the ones Lulzbot doesn’t appear to sell anymore? It there a bad way to install these? I soldered the molex connector to my lines and can now replace it easily using the molex connector it comes with. Clamped it in with only light force on the screw.

It appears I picked a bad time to have a printer problem. No one has used an E3D thermistor? No one at all??!??

It’s difficult to say if you got the correct one or not, I don’t think you did. This is the one you want - https://www.lulzbot.com/store/parts/100k-semitec-ntc-thermistor-235mm
As that is the one that’s used in the v3 dual print head. None are available on Lulzbot website and I couldn’t find any on Amazon or e-bay. Amongst other things yes you did pick a bad time to have printer problems. The best solution I can offer is to purchase one here: https://e3d-online.com/lulzbot-spares

Buy several and supply the community as their problems arise, help offset the increased cost from having to purchase from across the pond. Good Luck!

It is in stock at Filastruder and IT Works 3D.

https://www.filastruder.com/collections/e3d-spare-parts-and-accessories/products/e3d-thermistor-cartridge
https://itworks3d.com/product/thermistor-cartridge-e3d-v6-2/

In the past, I’ve read that soldering thermister wires are bad… something along the lines of affecting the resistance. Crimping seems to be the best way to go.

This is the exact same thermistor I got on amazon Semitec104GT in an encapsulated unit.

https://www.amazon.com/Genuine-E3D-Thermistor-Cartridge-E-SEMITEC-50-MOLEX/dp/B072HNL9MR/ref=sxts_sxwds-bia?keywords=thermistor&pd_rd_i=B072HNL9MR&pd_rd_r=c5311364-39cc-4c26-b6df-78a7a960e613&pd_rd_w=MIJNg&pd_rd_wg=nTrYD&pf_rd_p=a5491838-6a74-484e-8787-eb44c8f3b7ff&pf_rd_r=P6KYQSVWZ5BYYVQ8PYN1&psc=1&qid=1571447682

I didn’t solder the thermistor, it’s encapsulated and connectorized. Just the molex pins to my TAZ connector to make sure they were solid.

Thank you for the info though. I was considering soldering it without the connector.