supply line to shop

[peepee]

I tapped into a 1" PVC line from my well and brought it up through the stemwall form of my new shop, it will supply a hot water heater, sink and washing machine. I have 2 questions.

#1 what size of pipe do I supply the h/w heater with?

#2 when do I change to CPVC

#3 how do I change form PVC to CPVC

THANKS

[LazyPup]

PVC line is approved for direct burial and service (Line from source to the building), but not for distribution (lines within the structure) therefore you may run it underground and up to a main shutoff within the building.

The PVC line must be sleeved where it passes through the footer wall.

The Main shutoff valve should be located as close as possible to the point where the line enters the building but still allowing easy access.

The main shut off valve MUST BE a full bore type valve (gate valve or ball valve).

You may connect the PVC to the input side of a shutoff valve by means of a MALE thread adapter. (Female PVC thread adapters are prohibited by code.)

Connect the CPVC to the downstream (discharge side) of the main shutoff valve.

The line from the main shutoff valve to the HOT & Cold junction at the water heater should be a 3/4" line, where it then splits into 1/2" on both the hot and cold water systems.

Plastic lines (CPVC or PEX) may not be connected directly to the water heater. There must be a metal line, either copper or galvanized iron pipe a minimum of 12" from the top of the water heater.

Copper may not be directly coupled to a water heater vessel. If the risers or the distribution lines are copper there must be a dielectric coupling between the water heater iron vessel and the copper pipe.

There must be a full bore shutoff valve (ball or gate valve)on the water heater cold water supply line.

The must be a union within 12" of the water heater vessel.

For this installation the simplest method would be to attach a 1/2 x 12" galvanized iron pipe nipple to the water heater, attach a 1/2" Galv.Iron Pipe coupling and use a MALE cpvc thread adapter to connect the CPVC.

[peepee]

NextQuestion???? what kind of valve do I use at the PVC/CPVC union brass/ pvc/ copper????

[LazyPup]

Hopefully you have a submersible pump in the well so the 1" line you tapped into is on the discharge side of the pump, otherwise you will not have any water pressure.

The line coming from the well to the buiding is defined as the "Supply" line.

The "Main Shutoff Valve" defines the point of transition from the "Supply line" to the "Distribution lines".

PVC is listed as approved for "Supply" but it may not be used for "Distribution lines"

The code prohibits gluing disimilar plastics together (No PVC to CPVC) therefore the easy solution would be to run the PVC through the stem wall and to any convenient point as close to the point of entry as possible where the main water valve will remain readily accessible.

You could use a PVC male thread adapter to attach a Brass Ball Valve for a main water shutoff. (Female PVC thread adapters are prohibited by code)

You could then use a CPVC Male thread adapter to connect CPVC to the distribution side of the Main shutoff and continue the distribution with CPVC.

The supply line is only required to be a 3/4" line therefore you could run the 1" line all the way to the water heater junction or you could reduce the line to 3/4" at any convenient point from the point of entry to the water heater junction.

Both the Hot and Cold water lines downstream of the water heater junction should be 1/2" lines.

[mrcaptainbob]

Hey, Lazy.....I was under the impression tapping into the supply between the pump and the house was bad to do becuase of the possibility of contamination. The back backflushing from the house pressure caused problems. (don't know what kind ...was just told that was wrong to do...) Is that only for hydrants that are often incorrectly attached near the well?

[LazyPup]

MrCaptainbob,,
although it is not a code requirement it would be adviseable to install a double gate backflow preventer (dual checkvalve) on the supply side of the main water shutoff valve in both structures to prevent the possibility of backflow.

[peepee]

Thanks for the info!! To explain.... on my property I have two wells, the main well for the house, the second is to feel a pond for irrigation. the last owner of the property put in the second well and placed a 1" pvc line from the secondary well to the pump house of my main well were it was capped. it also has a valve at the secondary well that is closed. I had an open valve in the pump house, so i connected it to the 1" line and tapped into it for the shed which I poured a stem wall around it through a sheath.

[LazyPup]

Peepee,,

It sounds like you are set up fine now.

It sounds like you should end up with very good water pressure at the new location.

The code minimum for a supply line to a structure is 3/4" however having the 1" will compensate for line resistance and help insure full pressure at the new location.

Although we dont normally think of it as such, once the water reaches the water heater the system divides into two separate but equal water supply systems, the hot and the cold. The lines downstream of the water heater location are then reduced to 1/2 the volume of the main supply line to insure equal pressure on the hot and cold systems.

The capacity of a line is determined by its cross sectional area rather than diameter, therefore we must use the formula Large diameter squared divided by small diameter squared.

The primary supply line inside the structure is 3/4" and the distribution lines are 1/2" therefore it is (.75 x .75) / (.5 x .5) = 0.5625 / 0.25 = 2.25

Thus a 3/4" line has the same capacity as 2.25 lines of 1/2"

A simple rule of thumb is if you double the diameter you increase capacity by 4 times therefore your 1" supply line has the ability to carry 4 times as much water as the 1/2" lines at the same appplied pressure.

[mrcaptainbob]

Never heard of a double gate valve, LazyPup. Any chance of you doing one of your sketches? I may be able to use something like that for the barn. Would like to have at least cold running water there, and it's closer to the well than the house is. I'll be messing with that project this summer, I expect, and could incorporate it in the overall effort. By the way, the supply to the house is presently at 3/4" and is about 200' away. That WILL get revised

[LazyPup]

A double gate valve looks just like a regular gate valve but it has two internal gate flappers. You can find them in most big box home centers or plumbing supplies. Some local codes require them on the water main.

3/4" is code minimum for a residential supply line so you should not need to change that.