combined tpr pipe on 2 heaters - InspectionNews

Jerome W. Young · #1 (**permalink**) 02-06-2008, 05:05 PM

Any concerns with this?

John Arnold · #2 (**permalink**) 02-06-2008, 05:54 PM

It would be nice, if water is seen discharging from the tpr pipe, to know which unit it's coming from. So, yes, there are concerns. That's not allowed.

Jerry Peck · #3 (**permalink**) 02-06-2008, 07:29 PM

Jerome,

Until the 2001 Florida Building Code took effect in 2002, this was the code for all of Florida outside Miami-Dade and Broward counties:
From the old Standard Plumbing Code (underlining is mine)
- P504.7.1 Discharge. The discharge from the relief valve shall be piped full-size separately to the outside of the building or to an indirect waste receptor located inside the building. In areas subject to freezing, the relief valve shall discharge through an air gap into an indirect waste receptor located within a heated space, or by other approved means. The discharge shall be installed in a manner that does not cause personal injury or property damage and that is readily observable by the building occupants. The discharge from a relief valve shall not be trapped. The diameter of the discharge piping shall not be less than the diameter of the relief valve outlet. The discharge pipe shall be installed so as to drain by gravity flow and shall terminate atmospherically not more than 6 inches (153 mm) above the floor. The end of the discharge pipe shall not be threaded.

Now it is this:
From the 2001 through 2004 Florida codes (Plumbing Code in 2001, FRC in 2004).
- P2803.6.1 Relief outlet waste.
- - The outlet of a pressure, temperature or other relief valve shall not be directly connected to the drainage system.
- - 2803.6.1.1 Discharge.
- - - The relief valve shall discharge full size to a safe place of disposal such as the floor, water heater pan, outside the building or an indirect waste receptor. The discharge pipe shall not have any trapped sections and shall have a visible air gap or air gap fitting located in the same room as the water heater. The discharge shall be installed in a manner that does not cause personal injury to occupants in the immediate area or structural damage to the building.

NOT allowed by either code.

Jerome W. Young · #4 (**permalink**) 02-07-2008, 05:46 AM

Thanks Jerry

The new code appears more vague, especiallt with regards to termination location. It can terminate on the floor in a house? Is that how i read it?

Jerry McCarthy · #5 (**permalink**) 02-07-2008, 11:02 AM

So Jerry P, Florida allows the PTRV drain line to terminate into the WH's drain-pan? The IRC 2006 and California Plumbing Code do not.

Richard Stanley · #6 (**permalink**) 02-07-2008, 11:20 AM

The drain pan is an indirect waste receptor, is it not??

Jerry Peck · #7 (**permalink**) 02-07-2008, 03:51 PM

Quote:

Originally Posted by Jerry McCarthy

So Jerry P, Florida allows the PTRV drain line to terminate into the WH's drain-pan? The IRC 2006 and California Plumbing Code do not.

Jerry Mc.,

"The IRC 2006 ... do not."???

Where it that prohibited?

From the 2006 IRC.
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature relief valve or combination valve shall:

- - 1. Not be directly connected to the drainage system.
- - 2. Discharge through an air gap located in the same room as the water heater.
- - 3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
- - 4. Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
- - 5. Discharge to the floor, to an indirect waste receptor or to the outdoors. Where discharging to the outdoors in areas subject to freezing, discharge piping shall be first piped to an indirect waste receptor through an air gap located in a conditioned area.
- - 6. Discharge in a manner that does not cause personal injury or structural damage.
- - 7. Discharge to a termination point that is readily observable by the building occupants.
- - 8. Not be trapped.
- - 9. Be installed to flow by gravity.
- - 10. Not terminate more than 6 inches (152 mm) above the floor or waste receptor.
- - 11. Not have a threaded connection at the end of the piping.
- - 12. Not have valves or tee fittings.
- - 13. Be constructed of those materials listed in Section P2904.5 or materials tested, rated and approved for such use in accordance with ASME A112.4.1.

In fact, the reason this now shows Table P2904.5 is for that specific purpose - because the T&P was discharging to the drain pan and the drain pan line *was not* suitable for handling that hot of water: " - - 13. Be constructed of those materials listed in Section P2904.5 ... "

Robert Dalga · #8 (**permalink**) 02-08-2008, 06:30 AM

These units appear to be plumbed in 'series' not in 'parallel' like most units. If one of the units fail it will be more difficult to service. Moreover, unions are also missing making it that much more difficult to service the equipment.

Jerry Peck · #9 (**permalink**) 02-08-2008, 07:44 AM

Quote:

Originally Posted by Robert Dalga

These units appear to be plumbed in 'series' not in 'parallel' like most units.

I see about 50/50 plumbed series/parallel.

Each plumber can describe why the way they do it is better. After having listened to both for many times, I tend to agree with the 'series installed units provide more hot water for longer' plumbers.

Quote:

Moreover, unions are also missing making it that much more difficult to service the equipment.

Not really, with copper, the cold and hot just get sweated off, as does the connecting copper (in reality, the plumbers would just cut the copper, replacing the copper piece or use a coupling where they cut it). With galvanized, yes, absolutely, you would need unions.

Glenn Duxbury · #10 (**permalink**) 02-10-2008, 09:02 AM

"Up Here" = B.C., Canada, it is not allowed; AND

Elect. cables must also be sheathed in 'BX' (armoured)...

CHEERS !

-Glenn Duxbury, CHI
Glenn Duxbury & Associates-Building Inspection and Consulting