Leaky NRV?

[JOEPRO]

I had similar parts fail on my tandem compressor. I tried sanding them back etc but they still messed around.



So I replaced them with genuine parts from Italy at reasonable enough price. Had to modify the pipework slightly but no leaks or complaints since. (Tandem so it has 2x of these]

 

[voipio]

Using abrasive inevitably produces grooves and, if these grooves pass across the seal mating surface, leakage will occur. Even a small dink in the valve seat will pass air. This applies to other sealing situations too, like copper compression fittings. If I need to clean the ends of copper pipe with wire wool, the cleaning is always done using a turning motion around the pipe circumference, so any grooves run around the pipe, and NEVER lengthways. The same applies to cleaning copper pipe for use in push fittings. When we moved to one property, we found the kitchen sink unit carcass was sodden and black, all because a slight dink in the mating surface of the outlet for the dishwasher water supply had caused a slow leak. The previous owners never noticed it.

 

[dobbslc]

I did that. What a mistake. Every damn piece was a different width it took me an age to lay the floor, measuring the widths to get them near-matching for a run.

Don't say that! Was it Wickes flooring?
We had 3K's worth that I bought on a deal and stored for 18 months and it was like you said, it hadn't shrunk but was machined wrong. Luckily they replaced it as it has a 10 year manufacturers warranty.
The new replacement lot is still waiting to go down in the hallway...

 

[not done it yet]

That's a waste. It takes nearly 4 mins to charge the tank. Admittedly thats to 10 Bar.

That waste would be approx 1.5p? Guessing, here, your motor is 1 HP running at full load, leccy is 30p/unit and the compressor was stopped with a full receiver. There must be some safety gain by leaving the drain valve open between usage?

I don’t use my compressor that often, so it suits me - and some of that energy might come from the solar PV

That way also ensures the compressor will not fire up in the middle of the night, too.

 

[not done it yet]

Using abrasive inevitably produces grooves and, if these grooves pass across the seal mating surface, leakage will occur. Even a small dink in the valve seat will pass air. This applies to other sealing situations too, like copper compression fittings. If I need to clean the ends of copper pipe with wire wool, the cleaning is always done using a turning motion around the pipe circumference, so any grooves run around the pipe, and NEVER lengthways. The same applies to cleaning copper pipe for use in push fittings. When we moved to one property, we found the kitchen sink unit carcass was sodden and black, all because a slight dink in the mating surface of the outlet for the dishwasher water supply had caused a slow leak. The previous owners never noticed it.

If metals are contacting, they should be lapped together if not very positively forced together (like gas cylinder connections). If a resilient ‘washer’ (like an old fashioned tap), then the seal would deform with sufficient force applied. Force on the NRV should be proportional to the pressure difference across it.

 

[RWD3M]

That waste would be approx 1.5p? Guessing, here, your motor is 1 HP running at full load, leccy is 30p/unit and the compressor was stopped with a full receiver. There must be some safety gain by leaving the drain valve open between usage?

I don’t use my compressor that often, so it suits me - and some of that energy might come from the solar PV

That way also ensures the compressor will not fire up in the middle of the night, too.

Draining down not only wastes power (quite a lot in the case of my 2 x 3hp beast) but increases the fatigue cycles on the receiver. I personally wouldn't do it for both of these reasons. Additionally, maintaining pressure inside the receiver stops anything getting in that shouldn't be there.

Simply switching it off will stop it cutting in at night!