making my air conditioner switch on a fan

[philsvintageradios]

I am in the process of installing an air conditioner. we are using an attic room for a bedroom. I considered some options such as using the window, or cutting into a wall but then decided the noise would make it hard to sleep.

I then decided I could put the air conditioner in the basement, couple it to a blower and force air into the existing ductwork. The air will be then able to travel up to the attic, or into the other ductwork int the rest of the house. I figured I could have some control over how much goes to the attic by restricting flow past the first Y which goes to the attic.

So I adapted a blower , and coupled it to the air conditioner. I extended the wire on the heat sensor so it can go in the attic. I was considering moving the whole control panel to the attic so the remote would still work, but after lookingat how the unit is wired , it isn't easy to separate the electronics controls because the relays for the fan ,pump etc are on the same board which means I would have to run the AC wiring from the control box to the unit, this wasn't feasable.

so I came up with a new plan, which is to use a remote control extender to re-broadcast the remote control signal to the front of the AC unit. these are commercially available. I will live without being able to see the display, and go downstairs if I need to look at it .

The only other modification , other than extending the heat sensor , is that I want the blower to switch on along with the (3 speed fan) in the AC unit. the unit has a power saving mode and it would be nice if the blower could switch on and off along with the AC's 3 speed fan.

I don't want the load of the blower to come from the AC unit, so I was planning to use a 110V relay powered from the same wires supplying power to the AC unit's fan. , so the coil of the relay needs to be 110 and it just uses a bit of power to work the relay's coil. this would be a negligible ammount of power so wouldn't load the AC's circutry.

The blower is 110V . I can run the power wire to the blower through the contacts of the relay and that would work. The control cable would be carrying 110 and I don't know if that would comply to code or not. The other option is to use a small power supply to run a second relay at the blower, then the signal wire( through contacts of the added relay in the AC unit ) could be 12 or 24 V. this is a bit more complicated as I need a second relay and a 12 or 24V power source.

Which method of swithcing the blower on and off would be more acceptable? does it matter if the control cable carries 110V? would a relay be best or some sort of SCR?

Phil

[Noon-Air]

Good job Dr Frankenstein...um....I mean Phil.....now call somebody that knows WTF they are doing. That wheel has already been invented many times over.

Spend the money and get it done right....no, its not gonna be cheap, but the benifits will be far superior, and long lasting than your cobbled together .......ummmm.......mess

[philsvintageradios]

wow those two posts were more rude than helpful, but hopefully everyone on the group hasn't such an attitude. Phil

[Bubba]

Then Im sure you will like post #3. You have been watching too many episodes of MacGyver. Now bite me. Bubba

[Stormin Mormon]

Sounds like you're going to dump the waste heat into the cellar. Bad idea.

As to the fan relay, it's fine to switch 110 VAC, as long as you run sturdy enough wire for the job. Remember, cold air is heavier than warm air. So, the existing fan on the window AC won't be strong enough to push the heavy air up to the attic.

Put a current sensing relay on the neutral wire of the compressor, to switch the blower fan. Or take a 24 VAC transformer, and put it in parallel with the run windings of the compressor. Or, take another tap off the thermostat, and a neutral terminal block. Use the thermostat tap to power a 24 VAC relay, and use the relay to close the power circuit to the duct fan.

[Noon-Air]

You want attitude?, try this on for size... I have spent the last week fixing what home owners did in the name of saving a buck, including the simple fact that over half of them called the lowest price. and then had to call me to straighten it out and make it right. You can try and frankenstein anything you want, but remember that its gonna cost a lot more to get it fixed again and again, than it is to get it fixed correctly the first time. OTOH, maybe your here because you think you can save a buck. Just remember that most of the legitmate contractors right now are too busy with repairing and straightening out messes to have time to take care of their service agreement customers maintenence.

[KJPRO]

Crap snipped... It's time for you to hire a professional... as it's obvious that you are planning a FUBAR system.

[KJPRO]

No attitude, we just get tired of seeing perfectly good equipment ruined by idiots like yourself.

[KJPRO]

Looks like he found the right guy for the job... I mean girl... Miss Frankenstien.

[philsvintageradios]

Thanks cristopher . No , the plan wasn't to dump waste heat in the cellar, the ac unit will slide outside the house, it is quite cool on that side of the house and it is in an area that isn't closed in very tightly ( under the front porch), but it is dry and there is shelving to support it out of the way at almost ceiling hieght. there is a pipe straight up to the attic right there. all I need to do to close it up for winter is to pull the AC unit back a foot or two onto the existing shelf and the piece I need to cut out can hinge closed. I couldn't ask for a better place to store it when not in use. Yes I've hear about the difficulty with pushing cold air upwards. Im good with metal so I fabricated an adapter to pull the air from the area where the grille is on the ac unit to a cage fan style furnace blower. I need to modify the existing ductwork only to join in. the rest of the house isn't well sealed up as it is a 1920's house. just blowing fresh air up there is a benifit as the warm air wants to collect up there . The only ouside wall to have an AC unit on in the attic is the front of the house and that would look ugly from the front street, and I have gone to a lot of work to bring up all the old woodwork , and I think the plastic housing would really look like an eyesore. the AC in the window would need to be removed and a half window installed in it's place each spring and fall , the old windows swing out at the bottom so one need to be modified to even open that far. Maybe this wouldn't be suitable for a hot area, but it is quite cool here most of the year , only aout 2 or three days yet this year where it would have been unbearable to sleep up there.and would need AC at all , but I hate to have to sleep downstairs even a few days once we start using it as our bedroom. anyway it is cost effective for me, total cost is 169.00 for the air conditioner, the blower was free , If I don't like this setup it is reversible. I just don't see any air conditioners that would do this sort of thing in this price range. The portable ones seem to be getting more popular, but even they need to be stored somewhere and they aren't too attractive with their big plastic housings, and they are twice the price for the same BTU's. phil

[Zyp]

Phil;

Has anyone told you the FACT that the 'window air conditioner' wasn't designed to 'push' air through 'any' form of duct?

It's likely that there won't be enough air to support the refrigeration and, it will likely turn into a flaker.

Also, has anyone considered that since you're in the attic with a bedroom set that, possible the ceiling joists were not expected to carry the additional weight of a bedroom set and people, clothing, bedding, etc.?

Seems fine now, I'm sure, but wait until you hear the creaking sound. :)