Drain pan for tankless water heater?

I recently installed a Takagi Flash TK-jr tankless water heater. Let me first say that I absolutely love it, it performs flawlessly, and I've already seen a decrease in my gas bill.
That said, I removed the old tank unit and drain pan, and I did install a pressure relief valve on the new unit, complete with 3/4" copper drain line. The old copper drain line emptied into the pan, but it seems like a complete waste to install a huge round drain pan under this new, very small, tankless unit.
The UPC requires a watertight pan in attics, where it is, with a minimum 3/4" drain that terminates to the outside.
My question is.... what have others done for the tankless units? What kind of drain pan arrangement have you used?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
My Takagi Gas is in the basement near the sump if yours is in the attic instal a drain pan, I hope your attic does not freeze or you will need it when it blows, 31f is a bad environment for Tankless...Freezing....
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I didn't use a drain pan, I plumbed the T&P valve to run outside. I think the idea of having a water tight pan for attic installations is in the event of a tank rupture so you don't have 40 gallons of hot water flooding out your ceiling. With the tankless the heater is the strongest link in the chain. Since you have no tank to leak, a burst is more likely in the pipe going to or coming from the heater. In the event of a full on gas type failure, the T&P valve is going to relieve the pressure long before the pipes burst.
If the inspector demands a drain pan, have a sheet metal shop male a funnel type thing to hang under the heater with a drain you can either hook up to a hose or pipe to run across the attic and out the eve. Just be sure that the funnel does not interfere with gaining access to the heater for service.
--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.