Drip pans for preheaters - what is necessary?

[TimJ]

We've just finished the season on a home made oil tank evaporator with flat pans and we're eager to improve its performance.

I've been looking around here and on the internets for ideas and pictures of preheaters. We bought a very nice used 2x4 stainless hood to go over our 2x5 evaporator and plan on building a copper parallel preheater this summer.

However, I have not found great photos/plans for drip pans to collect and drain the condensation. I am specifically looking for details about the drain connection and how to set up the drip pans/channels.

After finding this last night I was very impressed. (http://s662.photobucket.com/home/bkm_photos/index ) - specifically what look like v channels under each cross pipe here (http://s662.photobucket.com/albums/uu349/bkm_photos/Oil%20Tank%20Evaporator/?action=view&current=evap-088.jpg&newest=1)

Some questions:

1. Would heat transfer be better with channels under each pipe run rather than one large drip pan with just a few inches on either side? (I think so)

2. What materials are considered safe for making the drip pan/channels and what mounting brackets are reasonable/suggested?

I'll probably suspend the hood a few inches over the pan and put the preheater up the hood a few inches.

3. Can I obviate the need for most of the drip pan by angling the preheater longitudinally? (As well as fore/aft for flowing in low side -> exiting high side) I suspect that is not good as the condensation will drip at each joint as a continuous flow will create drips.

I would prefer to use 3/4" for the parallel bits and 1" for manifolds, but it occurred to me after seeing the one in the link above that 1/2" has advantages in that it is easy to buy flexible feed line (faucet feeds) to use for connecting and disconnecting. Not sure if 3/4" feed lines are available.

Any opinions/experience on any of these questions and comments?

Thanks

[eschoon]

""link above that 1/2" has advantages in that it is easy to buy flexible feed line (faucet feeds) to use for connecting and disconnecting. Not sure if 3/4" feed lines are available. ""

I found a 3/4" flexible copper connecting pipe by the water heater parts in the local hardware store. I think it was aroun $15 and about 24" long. They also had some shorter ones- 18" I think

[brookledge]

most parralel pre heaters have a single pan under them. The pan is held in place using threaded rod so you can tilt it some to get the condensate to flow to a corner to drain out. Also some used drip channels around the perimeter. Steam will not condense back into water rapidly with out a big temperature differential. That is why it is most important to have a drip pan under the preheater and not so important around the perimeter.
Keith