Whole house electrostatic air cleaner

[bsudbrink]

Actually, this is a "possibly needs repair" issue.  The story:

I have a GAPA whole house air cleaner, attached to my HVAC system.  To be precise, it has the Bryant badge (but is identical to the Carrier unit), full product is GAPAAXBB1625.

Last summer, we had a slight flood (less than an inch of water) in the basement and the cardboard filter was dampened/ruined.  When discovered, the HVAC system was still running, but the light on the air cleaner front panel was out.  I turned everything off, cleaned everything up and dried everything.  When reassembled, the HVAC system ran (no surprise, really) but, much to my disappointment, the light on the air cleaner stayed off.  I pulled the air cleaner main unit again and decided to take a peak in the KIT62000 power supply.  It is closed with security TORX but that was no problem, I have a full set.  Anyway, there was no smell and nothing visually to indicate any problem.  Everything is lightly potted.  No apparent fuse.  Seeing nothing to do and needing air conditioning more than air cleaning, I put everything together again, turned it on and "lo and behold" the light came on.

So, why do I think it might not be working anyway?  We've had the cleaner for several years and I clean it and replace the filter every six months.  I've just finished doing it again and I noticed that the distinctive pattern of dirt on the filter, that has always been there before and seems to be related to the metal "points" on the "rails" in the unit, was missing.  The dirt was simply evenly distributed across the filter.

So I'm wondering how to test it.  I'm considering running a wire into the unit and testing it in place.  Some of the parts inside indicated that they were rated for 22KV.  My "best" meter has a 4.1 digit DC volt range, so I can't test it directly.

Finally, in addition to the service call, I'm reliably informed that a replacement power unit (it's non-repairable) is a couple of thousand dollars US.

[Armadillo]

To test it, a high voltage probe [example fluke 80k-40] can be use to measure the voltage, Yeah!, running a temporary wire in and maintaining it in Safety interlocked state [door switch] would be a good idea.
The circuit isn't that difficult, a step-up high impedance voltage source. That's about it.

I think the bulk of the cost is travelling long distance in the US, and cost associated with dismantling the unit from the ductworks and manhours charges etc.
But if you are handy with electronic and DIY, you can save alot of money with it.
Still, measuring 1KV or 2KV or 3KV....feel good for you? Don't know, but maybe a fluke 80K-6 would come in handy as well.

IMHO, Any products that do not have a testing and commissioning parameters and performance verification procedures in the manual, is just a marketing hype, Pseudo “Feel-Goods” device for the non-technical people. I mean, I will not believe in such product anyway.

I am not alone.

[james_s]

I've repaired several of the popular Honeywell electrostatic cleaners from the 80s, those usually tend to blow the power transistor. If you want to test the power supply it would be easy enough to bench test it. Supply power of the correct voltage and use a wire taped to the end of a plastic stick to see if you can draw a spark between the output terminals. Since they regularly arc in operation this shouldn't hurt anything.

[NiHaoMike]

If you can't fix the module, you can replace it with a bunch of X rated capacitors and 4007 diodes, as Big Clive has done. Simple and very reliable.

[Armadillo]

These modules are cheaply available nowadays;

https://www.ebay.com.sg/itm/DC-12V-to-20000V-High-Voltage-Electrostatic-Generator-Negative-Ion-Generator/201765577659?hash=item2efa2a63bb:g:d~kAAOSwUKxYZSNL:rk:2:pf:0

https://www.ebay.com.sg/itm/High-Voltage-Drive-Board-Electrostatic-Generator-Inverter-Module-Regulators/202298606739?hash=item2f19efc493:g:KwsAAOSwkela4Ojv:rk:4:pf:0

But when its cheap, somehow the voodoo "feel good" magic is no longer there until you part with couple of thousands... ..... Sshhhhhh..... just don't tell them the actual cost.

I have not tried those though.

[bsudbrink]

Ok, at james_s's suggestion (and I double checked the manual and the troubleshooting section said that the sound of arcing was normal), I ran a piece of heavily insulated wire from the "grid" to outside of the cleaner and taped it to a piece of broomstick.  The system is capable of generating a spark of a little more than a centimeter so I guess that's good.

While I was running the wire, I think I found the actual problem.  The air filter cartridges are laced through with a conductive material and there are a couple of foil contact pads on each side of them.  In the "slot" that the cartridge fits into, there are corresponding spring loaded contacts to ground the cartridge.  These contacts were tarnished and a bit rusted.  I cleaned them off with a combination of emery cloth and pink rubber eraser.  Hopefully, that will restore operation as I am used to it.  I'll report back in six months when I change the filter again.