How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Phil Your Own Question
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
Type Your HVAC Question Here...
Phil is online now
A new question is answered every 9 seconds

How and when do I change the nicad battery in an Alerton

Customer Question

How and when do I change the nicad battery in an Alerton BCM
Submitted: 2 years ago.
Category: HVAC
Expert:  MattR757 replied 2 years ago.
Officially, according to Alerton (and ALC for their controls) the on board button cell does not ever need replacing - because the battery should last longer than the expected service life of the control - The battery is supposed to have near 0 drain and is only there to provide voltage to the flash memory chips. We have a controls company locally who does battery replacement every 5 years. If the battery is not soldered in, you can just replace it without losing any settings or programming in memory. If it is soldered in, it's considered non-replaceable.
Customer: replied 2 years ago.
The controllers were installed in 1998 and the owner is concerned the batteries will fail.
Your answer suggests we can just remove the battery and replace it and the controller will continue as if nothing happened. I assume this is OK as long as we don't lose power during the changeover process.
Expert:  MattR757 replied 2 years ago.
Correct. The settings and addressing are stored in on board flash memory - kind of like a flash drive - that typically doesn't lose its memory even if powered off for a short time - Our controls guys just remove the old one and put in a new one without having to do anything to the programming or anything. I wouldn't be too concerned about the batteries going bad though. I've been told that the batteries are there mainly to protect on board factory programming during shelf time before install. I have ALC controls from Climatemaster equipment that are over 15 years old. I took the batteries out of the old controls and I use them in a small electric multimeter that takes the same size and I found they were still good for re-use.
Expert:  MattR757 replied 2 years ago.
Just to clarify, - Alerton states the battery is 10 year standby and 1.5 year service life - my experience is somewhat longer than that - but the battery is easily replaceable
Customer: replied 2 years ago.
Thank you.