How Is A-Coil Supported?

[PowerPlay]

I have a traditional system where the A/C A-coil resides above a vertical upflow gas furnace.

How is the weight of the A-coil supported? From below, by the furnace, or from above, by the supply duct?

I'm getting the furnace replaced and the new furnace will be significantly shorter than the existing one. I'm also wondering what is the best install method to adjust for this height difference.

[gregp]

a no-brainer for a good install crew. They should be able to answer all your questions.

[wahoo]

As Greg said, a good experienced install crew can easily take care of this. Make sure you get one!!

[bironacad]

How is the weight of the A-coil supported?

Very carefully, lol.

Support is just one of the considerations to coil installations. Air contamination from system drains. Type of furnace heat exchanger and Manufactures recommendations for height above it, Air flow and restrictions, air speed and volumes, appropriate temperature rise for heating system after a coil's install, correct temperature fall across the coil....... Yikes better call a qualified guy. With years of installation experience as a tin knocker I get my cousin involved with AC installs, he is a refrigeration mechanic and with him there I know I wont have to come back and listen to performance complaints.

[Cooked]

a no-brainer for a good install crew. They should be able to answer all your questions.

The coil is in it's own seperate sheet metal case and simply sits on top of the furnace. Good installers use powerful magic to suspend the coil/case in mid-air while the old furnace is removed and replaced. A good installer can do it by himself.

[sktn77a]

In general, the coil is supported by (attached to) the furnace. Some installations even have a flexible coupling between the coil and the supply ductwork, which wouldn't support any weight. The ductwork should not be supporting the weight of the coil.

[cuchulain]

If your new heater is shorter then the old one the installers will usually make some sort of transition to make up the difference, now if it's a real small difference and you have flex ducts instead of hard pipe for duct work and there is enough extra they may just lower it down to sit atop the new heater. without seeing our setup i can't tell you for sure, but your installers should be able to handle it with very little problems.

[catmanacman]

have the installers inspect and clean the coil while the furnace is removed

[hvacvegas]

[QUOTE=sktn77a;11297272]In general, the coil is supported by (attached to) the furnace. Some installations even have a flexible coupling between the coil and the supply ductwork, which wouldn't support any weight. The ductwork should not be supporting the weight of the coil.[/QUOTE]

Thats not entirely true.

There's plenty of times where you can build a support system in the plenum, and have to.

[bironacad]

The coil is in it's own separate sheet metal case

Don't get out much, eh, lol. Coils come in a variety of fashions which depends on the make and model.

Inspection and cleaning of the existing coil is recommended when you change out the furnace, some even install inspection ports just for future inspections, if the coil is sitting directly on the furnace not much chance for that, eh? We have never seen a plug coil right?

RTFM is also the rule of thumb for any installation.