So, as some who look in this forum know, I've been researching and learning about doing my own fills and settled on buying a compressor and making my own nitrox stick. Today, my brand new compressor arrived, and I promptly got to setting it up and getting it into service (without the nitrox stick at this point as I needed the compressor to determine the final fittings to connect the nitrox stick). Here's my current thoughts on it:
Compressor:
Coltri MCH-6, with stainless steel frame, 220v single-phase electric motor, auto-shutoff factory set for 3,750 psi.
Buying and getting the compressor:
Buying the compressor consisted of calling Nuvair (based in California), specifying what I was looking for/wanted, and getting that all sorted out. I elected to buy spares for the filters and oil at the same time as they were giving a 20% discount on those parts with compressor purchase so I got 7 extra breathing air filters, 5 inlet filters, and an extra gallon of oil on top of what comes with the compressor to start with. A PRV came standard as part of this model in the US, so I didn't have to pay extra for that, though from what I've read that may not be the case in Europe/elsewhere. I ordered the compressor the week before July 4th, and was told to expect it to be built the following week, tested and ship the week after that (12th-16th). It actually shipped the Tuesday the 27th, despite my salesperson telling me on the 14th that it was in line for testing and should ship "in the next day or two", then telling me on the 23rd that "it is shipping out today". There were a couple emails and one call I made in those last two weeks before it actually shipped that went without a timely response or any specific information given (including going to voicemail with no call back or email response for days). Needless to say, I wasn't thrilled with the customer service or timeliness of the shipping by the time it finally did ship.
It arrived today, with minor damage to the outside of the shipping box, but no damage to the interior parts. a random bolt and washer was loose inside, but does not appear to be missing from any of the connections on the unit itself. I wired up the plug after looking up the EU wiring colors as the wire came with brown, blue, green/yellow wires instead of US colors (the wires are 14 gauge for anyone interested, and are fine with a standard 3-prong 220v plug). The manual states that it ships without oil or a filter in it, but mine arrived with oil and the filter both already taken care of. That's nice as the qt of oil that comes with it was also still full, giving me an extra oil change worth of oil, and it shortened my time to get it in service today.
I bought an extended whip, with the upgraded whip adapter for filling DIN tanks with a pressure gauge on the whip end. In retrospect, I wouldn't get that end again as the pressure gauge is tiny and barely readable, certainly inadequate for any sort of gas blending. I'll be replacing that with a new pressure gauge I ordered today.
Operation is quite simple. The noise level is stated as 82db iirc, and it's pretty accurate. Standing 3 ft from the compressor it's possible to have a conversation without raising your voice. With the compressor inside the garage, and my work computer about 10' inside the house on the other side of the door to the garage I can barely tell the compressor is running (about the same noise level as the A/C running), so if a friend is pumping up a tank in the garage I could still be holding a Teams/Zoom meeting without anyone knowing there's a compressor going at the time. Blowing down the vents manually isn't much of a chore, but I was surprised to note that there is visible oil probably every 2-3 blowdowns (doing ~10 minute intervals) in the discharge from the moisture separator. I'll be keeping an eye on that and the oil level moving forward. Fill times are running about 8 minutes per 1,000psi in an AL80 tank. Going from 2,600 to 3,600 psi in LP95 doubles took 19 minutes. The auto-shutdown I purchased was set right at the 3,750psi I asked for, and with the slow fill rate gave me a final cooled off fill pressure on the doubles of right at 3,600 psi.
Overall, so far I'm pleased with the compressor, it's operation, and ease of setup, though I was disappointed with the communication and time it took to get it shipped in the first place. Not sure if seeing visible oil in the separator is normal or something I need to be concerned about, but I'll be keeping an eye on it and the breathing air filter. I'll also be placing oil absorbent pads under the moisture separator drain in the future. I plan on checking the visual indicator on the filter every hour of use for the first 15-20 hours and I'll replace that at the first sign of color change on the blue indicator, then track it's performance on the next filter to get a baseline.
I'm also looking at running the suction into the basement of the house to get cooler, dryer air for the compressor suction, which should extend filter life some I believe from my research.
I'll hook up the nitrox stick and route all that stuff later this week and try it out when doing fills next week probably. For use, I'll be doing a 30 minute rest period after any doubles filling as well, as my research suggests that the duty cycle is fine with doing AL80's but is best to not use continuously with larger volume/higher pressure fills.
Compressor:
Coltri MCH-6, with stainless steel frame, 220v single-phase electric motor, auto-shutoff factory set for 3,750 psi.
Buying and getting the compressor:
Buying the compressor consisted of calling Nuvair (based in California), specifying what I was looking for/wanted, and getting that all sorted out. I elected to buy spares for the filters and oil at the same time as they were giving a 20% discount on those parts with compressor purchase so I got 7 extra breathing air filters, 5 inlet filters, and an extra gallon of oil on top of what comes with the compressor to start with. A PRV came standard as part of this model in the US, so I didn't have to pay extra for that, though from what I've read that may not be the case in Europe/elsewhere. I ordered the compressor the week before July 4th, and was told to expect it to be built the following week, tested and ship the week after that (12th-16th). It actually shipped the Tuesday the 27th, despite my salesperson telling me on the 14th that it was in line for testing and should ship "in the next day or two", then telling me on the 23rd that "it is shipping out today". There were a couple emails and one call I made in those last two weeks before it actually shipped that went without a timely response or any specific information given (including going to voicemail with no call back or email response for days). Needless to say, I wasn't thrilled with the customer service or timeliness of the shipping by the time it finally did ship.
It arrived today, with minor damage to the outside of the shipping box, but no damage to the interior parts. a random bolt and washer was loose inside, but does not appear to be missing from any of the connections on the unit itself. I wired up the plug after looking up the EU wiring colors as the wire came with brown, blue, green/yellow wires instead of US colors (the wires are 14 gauge for anyone interested, and are fine with a standard 3-prong 220v plug). The manual states that it ships without oil or a filter in it, but mine arrived with oil and the filter both already taken care of. That's nice as the qt of oil that comes with it was also still full, giving me an extra oil change worth of oil, and it shortened my time to get it in service today.
I bought an extended whip, with the upgraded whip adapter for filling DIN tanks with a pressure gauge on the whip end. In retrospect, I wouldn't get that end again as the pressure gauge is tiny and barely readable, certainly inadequate for any sort of gas blending. I'll be replacing that with a new pressure gauge I ordered today.
Operation is quite simple. The noise level is stated as 82db iirc, and it's pretty accurate. Standing 3 ft from the compressor it's possible to have a conversation without raising your voice. With the compressor inside the garage, and my work computer about 10' inside the house on the other side of the door to the garage I can barely tell the compressor is running (about the same noise level as the A/C running), so if a friend is pumping up a tank in the garage I could still be holding a Teams/Zoom meeting without anyone knowing there's a compressor going at the time. Blowing down the vents manually isn't much of a chore, but I was surprised to note that there is visible oil probably every 2-3 blowdowns (doing ~10 minute intervals) in the discharge from the moisture separator. I'll be keeping an eye on that and the oil level moving forward. Fill times are running about 8 minutes per 1,000psi in an AL80 tank. Going from 2,600 to 3,600 psi in LP95 doubles took 19 minutes. The auto-shutdown I purchased was set right at the 3,750psi I asked for, and with the slow fill rate gave me a final cooled off fill pressure on the doubles of right at 3,600 psi.
Overall, so far I'm pleased with the compressor, it's operation, and ease of setup, though I was disappointed with the communication and time it took to get it shipped in the first place. Not sure if seeing visible oil in the separator is normal or something I need to be concerned about, but I'll be keeping an eye on it and the breathing air filter. I'll also be placing oil absorbent pads under the moisture separator drain in the future. I plan on checking the visual indicator on the filter every hour of use for the first 15-20 hours and I'll replace that at the first sign of color change on the blue indicator, then track it's performance on the next filter to get a baseline.
I'm also looking at running the suction into the basement of the house to get cooler, dryer air for the compressor suction, which should extend filter life some I believe from my research.
I'll hook up the nitrox stick and route all that stuff later this week and try it out when doing fills next week probably. For use, I'll be doing a 30 minute rest period after any doubles filling as well, as my research suggests that the duty cycle is fine with doing AL80's but is best to not use continuously with larger volume/higher pressure fills.
