Humidifier model question

[MurisonC]

I just had a contrator over to give an estimate for installing a humidifier in my home (suburbs of Denver and very dry). I've done some research including reading many forum posts here.

House: Built 2003, 2400 sq ft, gas furnace with central air, unfinished basement ~700 sq ft.

The contractor gave me a quote for an Aprilaire 700. I mentioned that I've read the 600 would be sufficient but he dismissed that outright. I also asked if the 700 would have an outdoor thermometer. He said no because it would also need a controller board and IAQ thermostat.

Based on what I've read, that doesn't sound right but I'm not an HVAC person (I was an electrician in a previous life). I'd like to hear what you all think and yes I'll be getting a second estimate.

Thanks,

Chuck

[beenthere]

Get another contractor. Or educate this one. guess what will be easier.

The 600 M will do fine for your ize home. Unless you have more then average air leakage into your house.

[BaldLoonie]

Yea, this one ain't too sharp!

600 & 700 have similar capacity. We use the 600 if at all possible. Simple, no motors or boards. If you want outdoor sensor capability, get a 600A or 700A.

[beenthere]

Yea, this one ain't too sharp!

600 & 700 have similar capacity. We use the 600 if at all possible. Simple, no motors or boards. If you want outdoor sensor capability, get a 600A or 700A.

LOL. The 600 is only about a ½ pint an hour less then the 700.

if that ½ pint makes the difference between maintaining the humidity in a 2400 sq ft house or not.
You have a lot of easy house sealing you can do to make it work.


Hmmm, That was suppose to be an A in my other post. need more coffee

[MurisonC]

Just to be clear, the A means automatic which requires the outdoor temp sensor and has the digital controller? Would there be any reason to get the manual mode in this situation (Denver area with central air)?

BTW, this is a great HVAC site. It's amazing what I've learned (how bad my HVAC install is) in the last two days.

Chuck

[beenthere]

No. With manual. You have to adjust your humidity down as it gets colder out. to prevent condensation on your windows. The automatic. Well, does it for you automatically. You may have to adjust it once. Since some homes windows aren't installed as well as others.

Yes, A automatic, M manual.

[JJDH]

All you need is the model 600a humidifier, it has a small outdoor sensor to read the temp so the humidistat which goes on the return air drop can auto adjust the hum to your setpoint. The model 700 is good when the 600 cant be put on the return, so the 700 first recommended placement is the supply. the difference between the output of the two is minimal.

[im4snow2000]

Curious when the model 700 makes sense, if the capacity is so similar to the 600?

[beenthere]

When you need every last single CFM of air that the furnace/heat pump can move to be delivered to the house. A bypass can reduce CFM (100 to 150 CFM) delivered to the house.

When temp rise across the heat exchanger(before you install a humidifier) is providing a discharge temp greater then 130°F.

[MurisonC]

One last question on the Aprilaire models. Do they constantly flush water down the drain or only when they are operating? Is it the same for both the 700 and 600?

Thanks,

Chuck

[beenthere]

Only when they are running. And its the same for any flow thru humidifier.
Which both the 600 and 700 are.

[MurisonC]

One last question on installation options for the AA600 before the next contractor comes over for an estimate so I don't get lied to again.

Can the 600 be installed on a return that is only 10" wide or will it have to go on the supply side? I uploaded three pictures. The return is on the left and is 10" wide and 25" deep front to back. I've read supply isn't prefered due to having water above the furnace electronics?

Thanks again for your advice.

Chuck

[beenthere]

The opening that gets cut is all but 10" wide. So it wouldn't mount real well.

In an absolute pinch. It could be done. But not advisable.