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View Full Version : T&P 3/4 IPS PORT AT TOP OF WATER HEATER HAS GAS DISCONNECT INSTEAD??



john stoneman
02-27-2013, 09:37 AM
In the city of Los Angeles Ca. I came across a condominium with each unit having individual water heaters in which a natural gas shut off safety valve was installed in place of the normally installed T&P valve at the top of the heater. This, I'm guessing, was done by someone that observed the fact that there is no way to properly run the 3/4 copper discharge from a T&P to the outside of the house without ripping up walls and ceilings (and I mean a lot of walls and a lot of ceilings). This condo was built I imagine when the T&P could run and terminate in the smitty pan. (Smitty pan has pvc darainage, easily destroyed with hot water discharge,let alone, if the releif valve ever blows, the scalding splatter of 210 degree hot water hitting the pan at a high rate of speed and increased pressure and seriously scalding anybody in its path was a concern and was the reason for the code change to down hill grade all the way to outside termination at a height between 2 and 6 inches from the ground with copper not PVC) My question: Is the gas line that feeds the w/h approved to connect in line with this special type of safety valve in place of the T&P? To me, this is an odd setup and is questionable. note there is a pressure relief valve on the system at water service supply to bldg. (after reg.) so the pressure end is covered. The temperature end at the heater, however, has no discharge relief. Only gas disconnect set at predetermined temp setting on this safety valve to shut gas off to thermstat when a safety breach is detected. I know that all res. gas w/heaters have a thermostat that has an internal "fuse" next to the temperature sensing bulb to terminate the gas valve operation permenantly if the tank water temperatre reaches 210 degrees. The gas valve/ thermostat must then be replaced before w/h use can continue.

Dom D'Agostino
02-28-2013, 06:24 AM
You're describing a Watts 210 gas valve, which shuts off the gas when the temp rises above 210. I think that they are no longer allowed in your area, but they are common for condos.

Robert Pike
03-01-2013, 05:46 PM
I see them as well condos and Town homes. Where do I find out if in fact it has been recalled or discontinued?

H.G. Watson, Sr.
03-02-2013, 09:12 AM
In the city of Los Angeles Ca. I came across a condominium with each unit having individual water heaters in which a natural gas shut off safety valve was installed in place of the normally installed T&P valve at the top of the heater. This, I'm guessing, was done by someone that observed the fact that there is no way to properly run the 3/4 copper discharge from a T&P to the outside of the house without ripping up walls and ceilings (and I mean a lot of walls and a lot of ceilings). This condo was built I imagine when the T&P could run and terminate in the smitty pan. (Smitty pan has pvc darainage, easily destroyed with hot water discharge,let alone, if the releif valve ever blows, the scalding splatter of 210 degree hot water hitting the pan at a high rate of speed and increased pressure and seriously scalding anybody in its path was a concern and was the reason for the code change to down hill grade all the way to outside termination at a height between 2 and 6 inches from the ground with copper not PVC) My question: Is the gas line that feeds the w/h approved to connect in line with this special type of safety valve in place of the T&P? To me, this is an odd setup and is questionable. note there is a pressure relief valve on the system at water service supply to bldg. (after reg.) so the pressure end is covered. The temperature end at the heater, however, has no discharge relief. Only gas disconnect set at predetermined temp setting on this safety valve to shut gas off to thermstat when a safety breach is detected. I know that all res. gas w/heaters have a thermostat that has an internal "fuse" next to the temperature sensing bulb to terminate the gas valve operation permenantly if the tank water temperatre reaches 210 degrees. The gas valve/ thermostat must then be replaced before w/h use can continue.A standard TPRV for a HWH opens at 150 psi and/or temperature set point. Release of both pressure and temperature energy at atmosphere when a TPRV opens.

I question the majority of your conclusions and commentary, what you state you "know", and esp. the 'instead' conclusionary title, as a PRV would still be required if a Watts 210 or similar (motion/earthquake safety shut-off) has been additionally employed. California state-wide has had specific requirements for storage-type water heaters for decades, requirements are NOT fully contained for every application, in any "one" title, chapter, or code book. Individual jurisdictions many times, have additional (more restrictive) requirements. A storage-type water heater =/+ 30 gals requires a safety pressure relief valve at a minimum not just a temperature relief valve for safety. I do not recall a "copper tube" only requirement for California state-wide, LA County-wide, nor LA City-wide. There are options/alternatives permissible. There is a distinction which is not made in your post "gas line" and "appliance connector", as to where the servicing shut-off valve and trap are present. Flexible connector methods are required for seismic requirements in california. Photos please.

Dana Bostick
03-03-2013, 08:45 AM
Pretty common here in CA when the TPRV cannot be easily drained by gravity to a safe location such as the exterior. Find them (or recommend them) for slabs with the water heater on an interior location, in basements with the W/H below grade etc. In all cases, per the manufacturer's installation instructions (see link above) a PRV IS required in addition.