Grundfos wc3 macerator

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Hello
doing a garage conversion to granny annex, soil approx 30 mtrs away, installed new manhole and connected 4 inch pipe to existing drain, for rodding and inspection. have buried 40 mm solvent under ground. Basically from macerator, direct 300 mm drop, level for 25 mtrs, then 45 degree rise 300 mm then 3 mtr run to falling 4 inch underground pipe to main drain.
Pipe from new manhole to garage loaded with water continuously, tested out with hose running into pump and can see a nice push (burst of water running to drain)
all seems well but a bit concerned or more so (don't like the thought of poo sitting in a pipe just hanging around to be pushed through to drain when shower, sink or loo is flushed )
just wanted to know if anybody can see any problems with install, or foresee any problems with install. Many thanks
 
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Any horizontal should have a fall on it and a rise after 25m will cause problems.
 
Wait til the Non Return Valve fails, it'll never switch off! I also suspect the Manufacturers will dismiss any warranty issues as it's not been installed as per instructions.
 
Wait til the Non Return Valve fails, it'll never switch off! I also suspect the Manufacturers will dismiss any warranty issues as it's not been installed as per instructions.
The NRV is largely made redundant because the pipe drops down at the start and whilst it will most likely outlive the warranty the rise at the end will shorten the life span of the unit..
 
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Thanks , but I couldn’t think of another way of getting waste away. I can live with the fact that units lifespan will be less as long as it works ok.
Looked around before this set up was decided.
Even run it past building inspector, who was out on one of my jobs, he thought it would be ok as long as I stuck to 45’s.
Could I change this , in a better way with the installed pipe work that I have ?
 
Is the direct 300mm drop creating a syphon when the motor stops? (can sound like water trickling back) if no then the section I would change is the rise at the end as the section before will always have old water in it.
 
Can’t really change the 300 mm rise at the end of the section as this is the point of lift via 2 x 45’s to get me into new manhole.
Set up from macerator is from top elbow through wall, down to ground 300 mm, 25 mtr and final lift to drain.
To be fair it seems to push very well when pump kicks in, just don’t like the fact of poo sitting in a pipe, waiting to enter drain only when other water is run. But I don’t suppose it’ll be a big deal to run tap for a couple of mins knowing that the pipe is only holding water .
I’ve put rodding points on the 45’s and can rod from saniflow to drain pretty easy.
It’s the fact I know nothing about this system,
And don’t really want to do a job which isn’t going to work.
Just tested again about syphon, and no noise of water running back, would an air admittance benifit on the 40 mm that comes out of wall.
run in 40mm thinking it would cope , as graph showed 5 mtr horizontal and 25 mtr vertical. thought that my 25 and 300 lift would easily be manageable.
 
Dont think of it as poo as t is a liquid slurry also reads that nothing can be done now with pipework. No need for the AAV if it isnt syphoning and good you can rod or flush it through. 25m horizontal on graph includes a fall and no rise at the end though.
 
I agree with the graph, and true that the rise is at the end of run. I can change pipework in ground if necessary, but only the same way I have done it in the 40mm. shame that the garden runs down to the garage and has to do that final 300mm lift uphill. I can not think of a solution that would be any different.
do you think that what I have done will work sufficient but shorten the machines life expectancy ?. or completely fail from the get go.
would sooner change if I have to
 
I agree with the graph, and true that the rise is at the end of run. I can change pipework in ground if necessary, but only the same way I have done it in the 40mm. shame that the garden runs down to the garage and has to do that final 300mm lift uphill. I can not think of a solution that would be any different.
do you think that what I have done will work sufficient but shorten the machines life expectancy ?. or completely fail from the get go.
would sooner change if I have to
It will work for a fair few years.
 

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