Water heater - natural gas - black iron rebuild with flexible CSST

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Tbbarch

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I am dealing with a water heater installation I hired out 18 years ago.
The tank was installed so that the relief valve is obstructed by the wall and can not be removed.
Now the T&P valve is leaking and I have to do some exercise to get at it.

The tank has to be turned 3".
This requires the water lines to be disconnected and reconfigured for the turned tank
- I'm looking to use flexible copper lines for the hot and cold water connections.
The gas supply has to be disassembled and reconfigured.

Between the ICC and the broad world of installation images I would like some input on my I plan to reconfigure the gas line with CSST.

Reading the gas code the valve needs to be before the CSST and sediment trap.
See photo of existing.
I'm thinking to remove the shut-off from the location in the picture and connect one end of the CSST there.
Then reinstall the shut-off at the T from the gas line and the other end of the CSST to it.

1)
What I am unsure of is if the sediment trap needs to be immediately after the valve or if it is appropriate to leave it where it is right in front of the water heater thermostat.

2)
I see on the BrassCraft site their CSST is for internal pressure up to 1/2 psi. If I read correctly the pressure from the gas company is 2 PSIG. What is the distinction between 1/2 psi and 2 PSIG?

Thank you
 

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Reach4

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What is the distinction between 1/2 psi and 2 PSIG?
That is the easy one. Most residences in the US have gas at "6 inch water column" pressure, which is about 0.22 PSI. 2 PSI is about 9 times higher, so it can use smaller pipe. An appliance would either have to be set up for 2 PSI, or you would need a regulator to reduce the pressure to the appliance.

1/2 PSI is 6 inch water column with some margin added in.

I expect somebody can help you with the harder stuff. I think I have read that a sediment trap is no longer requires some places.
 

Jadnashua

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There are lots of flexible gas supply lines designed for attaching to your gas appliance. NOw, some places require a hard-piped connection, and some places require a flexible one (earthquake country), some allow either, so you need to check your local requirements. Personally, I'm not sure I'd play with an 18-year old gas WH...the average life is less than half of that.
 

Tbbarch

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In my jurisdiction, 2012 Fuel Gas Code applies:

SECTION 411 (IFGC) APPLIANCE AND MANUFACTURED HOME CONNECTIONS
411.1 Connecting appliances. (... plus other not related)
...
2. Corrugated stainless steel tubing (CSST) where installed in accordance with the manufacturer’s instructions.

In talking to BrassCraft they started talking of other types ... CSSC. (?)
Any insight into this or other acronyms related to corrugated stainless steel?

I suppose to move things along and get back to using hot water -
I'll leave the sediment trap attached ahead of the water heater thermostat and install a second one below the shut-off valve and take the CSST off of the T above the first sediment trap.

The only place I see 1/2 psi reference for gas pressure is in a emergency response report that says natural gas pressure in homes is 1/2 psi after the regulator.

I see that code revisions are in the works for requiring all systems using CSST to be electrically bonded ... grounded to the service panel.
 

Tbbarch

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I suppose to move things along and get back to using hot water -
I'll leave the sediment trap attached ahead of the water heater thermostat and install a second one below the shut-off valve and take the CSST off of the T above the first sediment trap.

... then again maybe not.

I found some install instructions and now understand flex pipe and fittings are designed to be one use, disposable items.
The hot water heater calls for 1/2" MIP.
The hot water heater flex connector is 3/8" ID though the connector fittings are 1/2" MIP/FIP.
The flex pipe is supposed to be directly connected to the appliance.

The VA Fuel Gas Code / 408.4: calls for a sediment trap shall be installed downstream of the appliance shutoff valve as close to the inlet of the appliance as practical.

I see applications, on the web, where CSST goes to a black pipe and sediment trap.

Practical ... how does that apply in this situation?
 

Tbbarch

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Follow-up:
Corrugated Stainless Steel Tubing is sized by the BTUH demand of the appliance.

BrassCraft; 1/2" OD, CSSD is rated for BTUH based on its length.
I needed 24" for a water heater demand of 40k BTUH. BrassCraft instructs to select the next larger BTU rating which was 85k btu.

CSST, CSSD, CSSL ... have to do the diameter of the tubing.

I did install a second sediment trap before the water heater thermostat along with a Union so I could potentially remove the flex line to one side and reconnect it to a new water heater if efforts to continue use of the tank fail.

Re: precautions on working on old water heaters
I found once tip that made sense on working with old water heaters and that was to let the tank cool down before flushing it so there would be no thermal shock.

I'm working on a Bradford White water heater that is 18 year old. It took about 30 gallons of flushing to get the brown tint out of the water and there was very little solid material. The solids looked like whitish fish scales - I assume it was calcium.

I was able to rotate the tank and fully operate the relief valve to flush it. As of now the relief valve is holding EXCEPT when I take a shower. I will get back with how that sorts out. I found the T&P valve is a standard part produced by WATTS and sized to the water heater.
 
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