My friend tells me this is an odd setup

[giddonah]

So I go help my friend finish an install at a new lake house that was started by some other people. This is Sullivan County, NY. Cold in the winter, hot in the summer, 80mi NW of NYC.

Anyway, they have radiant floor heating and two a/c units on each side of the house (wired together to act as one system, no zones). They have the thing hooked up to multiple humidistats (kitchen, bathrooms, bedrooms). But the bathrooms don't have separate fans, they just depend on the a/c to move the humid air out. So, there is an air handler in the basement with two supplies (7") and four returns (6") and a humidifier. They had us wire the kitchen humidistat into the humidifier (via a relay).

Ok, so, the kitchen says it's dry, turn up the humidity and the system blows humid air. The bathroom says it's humid and all its humidistat can do is say "blow air". So, the bathroom gets humid air blown into it because the kitchen is dry.

Is this a totally messed up system or what? All we could do is get the thing running and wire it up how they wanted. We had no control over the install and were only there to finish. Is there an easy way to get this system to work normally? We're not compelled to fix it at all, we were just there to hook it up. :roll:

[rabadger]

The units are wired for twin operation. I have done it before but, you are right. Its messed up.
If they are trying to control humidity only thats the wrong way.

Why would you want to add humidity? Is this thing for the winter months only? You know residential A/C does not work well below 40 degrees. The have to add fan cycling, low and high pressure controls.

[giddonah]

They decided to add central air after the house was nearly finished. I'm sure they didn't do any calculations, the whole thing was so slapped together. They insisted on going this route even against my friend's advice. You'd like my friend Rich, except he likes flex duct :D

I'm guessing the humidifier is only supposed to be for the winter. But they don't have forced air, it's radiant heat, so it's not like the heating is going to dry the house out. Plus, the thing is on a lake. And if someone is baking and dries out the kitchen, the humidifier gets turned on. This place is a call-back waiting to happen. I think they might call when the bathrooms start getting moldy :lol: . Beautiful view though, back deck is 20ft from the water.

[rabadger]

Find a good reason not to do the job.

[giddonah]

It's done. We hooked it up and it'll run, but I can't believe it will run right. We aren't under any obligation to fix it at all, the owner of the company understands that it's not the best install. I was just wondering if there was something easy that could be done in the spirit of samaritanism, I thought I'd ask (and give a chance to share the story).

[rabadger]

I don't know. How big is this place? Why two units?

[rabadger]

This is wild!

[rabadger]

For the air in one part of the home to accept humidity from the other part it must be warmer and drier.

Humidity is smart. It will seek its own level.

[giddonah]

It's a pretty big house, I'm no good at sq ft estimates. I think it's two units because it wasn't planned and was slapped in at the last minute I imagine. I think the h.o. is just screwed. For it to work right, he'd have to install bathroom vent fans at the least. For it to really work like they want, the system needs a smarter controller than just a relay. Humid in the kitchen and dry in the bedroom? Drink some water. :lol:

[rabadger]

How oversized do you think the units are?

Seperate the unit controls.

Get the flex as straight as possible

Make sure you have plenty of return air (old rule of thumb SHAME ON ME! is 20% more return)

Use standard theromstats for the cooling and standard humidistats for humidifier control.

If they need dehumidification add low ambient controls and duct heater with duct mounted discharge temp control

Have a waiver signed showing they were warned about compressor loss. No warranty because products are not being applied within factory specifications for use.

One day before start up, leave the country.

[giddonah]

Thanks for the thoughts Richard. I don't know what size the units are, I was only in the basement running the duct to the air handler and humidifier. I'll run this by my friend and see if we'll even say anything to the owner or not. Chances are, they won't want to change anything until it gets proved to them (by experience) that the system doesn't run right. We'll know what to do then though. Thanks.

[rabadger]

Good Luck!