Advice on replacing main sewer pipe please

[BasicPoke]

I need to replace the pipe from my house to my septic tank, because it is partially collapsed (on the lower portion, which is thinner pipe), and install a cleanout. The house was built in 1977. The pipe coming out of the slab is fairly thick and is stamped PLASTIC in black. Diameter is 4 1/2 inches. As you can see, it goes through a multitude of connections, some of which I don't understand (it looks like a smaller pipe was just slipped inside a larger pipe). The elevation needs to drop about 1 ft. Any advice will help. See attachments.

Questions:

1. What is this type of old main pipe called and how do I connect to it?
2. Do I likely just need a standard 4" pipe into the septic tank?
3. How should I seal the pipe to the septic tank inlet (It goes thru a round hole that is roughly 4" but a bit larger)?

Thanks a lot
BasicPoke

 

[johnjh2o]

It looks like the line through the slab is SCH 40 PVC. Then it connects to 3034 PVC. I would suggest you use all SCH 40 PVC. Cut the existing line behind the hole that was cut into the pipe. Start out with a clean out tee. Followed by two 45's and SCH 40 pipe to the tank. Be sure to use PVC cement and primer on all the joints and cement the new line into the tank. Do not push the new line to far into the tank as there may be a baffle in the tank.

John

 

[BasicPoke]

Thanks John. What concerns me is that the pipe coming out of the slab is 4 1/2" diameter. The standard 4" PVC would be about 4", right? What type of cement should I use to seal to the septic tank? There is a cover in the tank near the inlet and I plan to install a PVC baffle. I believe the old one was concrete and is gone now.
BasicPoke

It looks like the line through the slab is SCH 40 PVC. Then it connects to 3034 PVC. I would suggest you use all SCH 40 PVC. Cut the existing line behind the hole that was cut into the pipe. Start out with a clean out tee. Followed by two 45's and SCH 40 pipe to the tank. Be sure to use PVC cement and primer on all the joints and cement the new line into the tank. Do not push the new line to far into the tank as there may be a baffle in the tank.

John

 

[phishfood]

The outside of Schedule 40 PVC is just about 4 1/2".

I use hydraulic cement to seal to the tank, because I am impatient and don't want to wait for regular cement to dry. You have to work very fast and with small batches of that stuff, it sets up very quickly.

 

[BasicPoke]

What would be the proper cement to connect the PVC to the septic tank? I mean exactly what is it called?

For a cleanout can I use just a standard 4" tee, like I have seen at Lowe's, or should I get one of those with more gentle curves?

What would be the ideal distance for a cleanout tee from the house, or should I worry about that?

Thanks
BasicPoke

 

[johnjh2o]

Use PVC regular cement with purple primer. For a cleanout you could use a clean out tee or a sanitary tee with a cleanout plug. I would put the cleanout were the line first exits the house.

John

 

[BasicPoke]

Over the past several weeks, I have replaced the pipe, including a clean-out, added a baffle at the inlet, and replaced the effluent pump with a heftier one and different float configuration. One of the tougher decisions was how to seal the pipe to the concrete septic tank. I ended up using roofing asphalt (pretty much tar). The tar did not harden after a couple of weeks and I was reluctant to pile dirt on top of it. It all seems to be good now. See photos. My shovel and I are good friends now. Thanks for all the suggestions.

 

[KULTULZ]

NICE JOB!

But where does the sump pump come into it?

 

[phishfood]

My guess is that the pump lifts the effluent (sewage out of the septic tank) up to an elevated drain field.

Nice looking job.

 

[johnjh2o]

Good job ,but I hope you used primer on those joints. I don't see any purple. Hopefully you used clear primer.

John

 

[phishfood]

The second picture, it looks as though there is a fleck of purple above the cleanout tee. And on the inside of the tank tee in the first picture. Basic Poke is definitely a lot more careful with his purple primer than I am, though.

 

[DetroitRob]

Hvac guys are the worst with sloppy primer!

 

[KULTULZ]

My guess is that the pump lifts the effluent (sewage out of the septic tank) up to an elevated drain field.

Nice looking job.

...hmmpf....

So in place of a holding tank, the water and effluent is pumped into the field? Or does the sump pump only lift out water above the effluent level?

Help me out here as I am on a steep learning curve...

 

[johnjh2o]

Water flows first to the septic tank, then into the pump chamber which pumps it into the elevated drain field.

John

 

[KULTULZ]

OK... I think that explanation sank in. THANX!

The main tank still has to be pumped at intervals. It is only transferring water to an elevated septic field?

My factoid for the day...

You never know when you might need to know this...

 

[BasicPoke]

Yes I used a blue PVC primer and glue on the joints. I tend to be a perfectionist so didn't make much of a mess...I wouldn't say it's an elevated drainfield. It was just a normal septic system, but it was not working well at all when the yard was wet, especially in the winter when there is not much evaporation. So my septic specialist installed the pump chamber between the septic tank and leech field. I suppose you could say my leech field was failing, but it works just fine with this pump.
Ron

 

[johnjh2o]

I'm not saying your specialist is wrong but if a drain field can take the water with a pump I don't see why it wouldn't by gravity.

John

 

[IFIXH20]

Check your new pump manual to see if the pump is manufactured with a weep hole, if not , drill a 1/8'' hole in the discharge line between the pump and the check valve (usually just above the mip adapter at the pump). The weep hole prevents air locking.