Ultra Aire 155 dehumidifier died - need opinion

[wxperson]

Hi,

I have had two Ultra Air 155xt dehumidifier.. THe first one died after about 1 year and was replaced. The replacement died in 9 months. Thermistor company has replaced both units under warranty.

I am trying to figure out was happened with the 2nd unit and have some temperature and dew point charts during its death as an analysis tool.

Note.... I am a meteorologist and have sensors around the house, crawl space and near the output from the dehumidifier. These charts are readings taken near the output. The input temperatures in the house were in the 65-70 degree range.

The charts should appear at the bottom of this post (if I am doing this right).

The first chart shows the output dewpoints over a 3 day period. Around noon on the 18th... things start to get interesting with the unit apparently cycling for about 24 hours before it stops cycling and also stops removing moisture.

The temperature and humidity charts support the same behavior.

I am hoping someone here might be able to speculate what went wrong? Ultra aire support seems to think that it is a refrigerant leak or compressor issue. I am wondering if the cycling caused a problem or the cycling was a result of the problem.

We have another new unit (3rd) but remain concerned over the quality of the equipment. Any ideas would be appreciated.

Thanks,

George

[wxperson]

Teddy Bear... Do you have any ideas on this? Thanks.

[ksefan]

Refrigerant leaks are common on dehumidifiers in my area. We have condos that need the Honeywell Dehus replaced every 2 years.

[wxperson]

Refrigerant leaks are common on dehumidifiers in my area. We have condos that need the Honeywell Dehus replaced every 2 years.

Thanks... makes you wonder why anyone would pay thousands of dollars for these higher end units.

[ksefan]

Better off buying a window ac, set it in the crawl space or basement and let it recirculate.

[wxperson]

Teddy Bear.... Do you have any thoughts on this? Thanks... George

[teddy bear]

All have had fun with cooling coil refrigerant leaks. All Therma-Stor coils are epoxy coated and baked. This has dramatically reduced the leaks, but still have occasional leak. Probably chemicals in the conditioned air.
The longer running cycles appear to indicate slow refrigerant leak.
Most Therma-Stor units have 6 year coil warranty plus steady improvements is manufacturing and design of the coils.
20 years ago we had much less coil problems???? The old units are still running.
Thanks for the support and we will do our best.
Regards Teddy Bear

[wxperson]

All have had fun with cooling coil refrigerant leaks. All Therma-Stor coils are epoxy coated and baked. This has dramatically reduced the leaks, but still have occasional leak. Probably chemicals in the conditioned air.
The longer running cycles appear to indicate slow refrigerant leak.
Most Therma-Stor units have 6 year coil warranty plus steady improvements is manufacturing and design of the coils.
20 years ago we had much less coil problems???? The old units are still running.
Thanks for the support and we will do our best.
Regards Teddy Bear

Thanks for the reply. The one curious thing on the dewpoint chart was the sudden drop at noon on the 18th where it went down to 33... then the cycling started.

Does that indicate anything interesting?

George

[teddy bear]

Probably a freeze-up of coil as the unit died. Or could have been an strong dip in outdoor dew point?
Regards Teddy Bear

[wxperson]

Probably a freeze-up of coil as the unit died. Or could have been an strong dip in outdoor dew point?
Regards Teddy Bear

Hi... probably the freeze-up was due to unit dying. outdoor DP was steady in low/mid 40s at the time.

[hvacvegas]

If it means anything, we've been burning through aprilaire dehums.

[wxperson]

That's what I have heard.. that this seems to be a universal issue. Certainly there is a solution to this problem... or do the manufacturers see it as a opportunity for continued/renewed sales.

Good reason to make sure you get a decent warranty.

[teddy bear]

That's what I have heard.. that this seems to be a universal issue. Certainly there is a solution to this problem... or do the manufacturers see it as a opportunity for continued/renewed sales.

Good reason to make sure you get a decent warranty.

20 years ago we had <2% failure rate without any special treating or coatings.
We are currently struggling to get that low with the best of coatings and details. The failure rate has declined significantly in the last 2-3 years.

Thanks for your tolerance.
Regards Teddy Bear

[wxperson]

maybe a dumb question but why don't we see the same issues with Central AC units? Is it because they are outside of the home?

[teddy bear]

Good question. Maybe the difference in running hours and dehu coils may be colder. A/cs have plenty of failures also.
We will keep on trying to improve.
Large coils have thicker copper tubing?
Regards Teddy Bear