I am looking to install a toilet 90 feet away from a 8 inch clay sewer line.
Not having access to surveying equipment, I set up a cheap laser on top of a levelled 3 foot level and made measurements indicating not more than a foot of incline from the level of where a macerator equipped toilet's outlet pipe would be to the pipe.
Similar degree of rough figuring using the level of blocks in a retaining wall adjacent to the run shows them to be approximately at the same level, not indicating an incline.
So those are likely the best and worst case scenarios for the calculation of relative elevations.

What would be the minimal recommendations for height of head of water/ horizontal pumping capability for a lightly used toilet with macerator pump (not sump pump)?

What would be the minimal diameter of pvc pipe that I should use for the 90 foot run?

Thanks!

can't answer part of the question without knowing the make and model of the pump.

the size of the drain pipe as recommended by sani-flo is 3/4 or one inch.

put a ball valve in the pipe for future service.

go to sani-flo's site for lots of DIY information.

I am looking for guidance as to what the minimum requirements of the macerator pump should have to comply with prior to getting stuck with one that either would not make the grade (literally), or cost me hundreds of dollars more than necessary to get the job done.

I am also aware that there is a greater frictional load on the pump's discharge if it is getting squeezed through a narrower pipe for a relatively longer distance. Yet a wider than nominally needed pipe diameter would pose other problems, so guidance needed with this aspect also.

Still hoping that someone with enough experience in similar situation(s)/ enough of a true understanding of involved underlying theory will be able to pitch in to help solve this riddle.

the 'theory' involves a knowledge of the specific pump involved and its' "pump curve"

eg.:


"..... waste to a macerating pump which disintegrates waste and pumps it out up to an 18-Foot vertical rise and 150-Foot horizontal run in less than 3 seconds. A strong suction draws waste into the unit and a uniquely-molded blade prevents materials from getting clogged. The system includes vitreous china, rear discharge toilet bowl; toilet tank and the macerating pump. The pump includes a 1-1/4-Inch outlet for waste and water, 1-1/2-Inch vent, 1 1/2-Inch inlet for a sink and a 2-Inch inlet for a shower/tub. If a sink or shower/tub is not used the inlets can be capped off. ....."

"The xyz Pro is a durable macerating pump designed to facilitate full bathroom additions. Capable of pumping vertically up to 25 feet, the xyz Pro connects with standard, bottom-outlet toilets, washing machines, toilets, sinks, showers, and/or bathtubs to process effluent and pump it vertically up to 25 feet, and horizontally up to 150 feet."

[www.saniflodepot.com]

[www.bing.com]

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

What values must be attained on a pump curve to pump macerated effluent from a single lightly used toilet 1 foot uphill over a distance of 90 feet?

How should one decide on the minimum diameter of pipe needed for the recommendation to continue to ring true for the needed 90 foot run?

ask an engineer

a plumber merely give job specs to a 'supplier' and buys whatever meets them (as per the vendor's info)

IMO: the actual answer to your question depends upon the Hazen Williams formula which needs ALL of the following data:

Specific Gravity of liquid/slurry to be moved

SPECIFIC type of pipe to be used (interior 'roughness' / frictional co-efficient

Length of pipe run

Number and type of fittings

Slope / elevation change

[www.easycalculation.com]



good luck

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

When you order an inspection, the entire tank will be pumped at that time. However, an inspection might fail if the tank has been pumped before. That is because you cannot know the status of an empty tank