[tekgeek1]

So we currently have a Aprilarie 600 system that simply stopped working due to age. So we need to replace it - reading things indicates that the steam humidifier (Aprilaire 800) is the most efficient for getting real humidity into the house but the cost for the unit sn installation approches $2K with a higher operting cost due to the power required.

The Aprilaire 700 (automatic) can be controlled via my Nest now and we have the furnance blower always on low to circulate the air.

- If the blower is on low, will the 700 unit work or does it only kick-in with the blower is on high?
- Is a 2x in price between pad and steam a worthwhile investment?

Help and any advice please since when I ask our HVAC guys they always say steam but since that is more $$ for them....just want to make sure I choose smart.

 

[yuri]

If the 600 did a proper job and you were not too dry then the 700 is all you need in terms of capacity.

It has a G terminal to start the furnace fan but the installer can leave it disconnected as you already have the fan running thru G on the thermostat. High speed will get turned on when the heat is on by the furnace circuit board.

If you are very dry and need a lot more humidity then the steam units are awesome with the massive amount they can produce.

 

[u3b3rg33k]

the 600 is so simple, how did it just "stop working"? either the solenoid is dead/clogged, or the pad needs changing. it only has one moving part (the solenoid).

 

[user_12345a]

steam can burn up a lot of electricity and may need more maintenance due to scale buildup.

 

[1984babybenz]

If your 600 worked than the 700 should do just fine, no use spending twice as much. I have my 700 set to only go on when the furnace is on, and it still makes the house comfortable. No issues with wood shrinkage or expansion

 

[u3b3rg33k]

I've had good luck with steam systems (resistance, not electrode, haven't tried those) and RO water. after two years they have a barely noticeable white dust. I wouldn't install steam without RO.

I currently have an Aprilarie 600. I can't say I'm impressed with it, but it is useful. I may be happier once I finally fix some drafts and bad windows. I have tried it with fan only and heat, and with fan only there is no measurable humidity output. I can't imagine the 700 does much better without heat.

remember, their "up to" output numbers mean 24/7 operation, so take that with a grain of salt.

 

[supers05]

Steam can work without the running heating. Pads require warm and fairly dry air to work effectively, even with hot water running through them. (most people use cold water.)

I haven't tried the residential versions, but the commercial versions manage scale buildup quite nicely. They will occasionally purge water down the drain to flush the highly concentrated water. Sizing is fairly critical, as they can keep pumping plenty of steam even as the humidity climbs. You can end up with large swings in humidity. Worse case is that you have a rainforest in your house,

For pads, my preference is the bypass versions, or the fan powered versions that recirculate supply air. Like I said, they require heating to be running or they don't do so well. They are less efficient as humidity climbs, so you have to consider that too. (Their "up to" numbers are not just 24/7 but also with very low humidity and hot water supply.) The good side of that is that it reduces the swing in humidity, causing it to run longer, and giving more comfort. If the 600 was working mostly fine, you don't need the steam.

Cheers!

 

[beenthere]

If the 600 did a good job, I'd stay with a 600.