Shopping for a good quality compressor

[michael Friesen]

Hello,

My aquarium is looking in acquiring a compressor for our facility. We are tired of driving 30 minutes out of town to get refills.

Honestly I never shopped for a compressor, don't know what to look for. My needs are:
-new
-electric
-doesn't need to be portable
-Size doesn't matter
-About 8 bottles/ week (can vary, occasionally reaches 15 fills/week)
-Good quality (very little repairs) is very important
-Low maintenance cost and down time
-not too noisy (we can be flexible on this point)

Everything above is priority, after that low purchase cost is important too.

If you have any model suggestions to look deeper into it would be much appreciated.

Thanks

 

[justinthedeeps]

A Coltri unit via Nuvair is a good option, just got one from them recently.

MCH-6 is compact
MCH-11 is higher throughput, one fewer stage to maintain, possibly quieter. Single-phase 5.5HP motor can run on a 50-60amp 220V circuit (kinda like an EV charging circuit)

Allow at least 1-2 months for a new order

 

[rhwestfall]

got a fire department close by?

 

[TravisD]

Since you mention noise - consider adding a small cascade/bank to the setup - this will let you run the compressor at times when noise might not be as much of an issue, and also when general conditions (ambient temp) are more favorable (helps with filter life). Make sure the compressor is rated for the duty cycle required to fill the banks though...

Are you capable of self maintenance/repair? If not, then look for something with a local support network. A local vendor may also be able to source a good low-hour used model for you, especially if they support/maintain the local fire stations.

Other considerations - do you need High Pressure (3500+) fills? Who will be operating the unit? If you don't get automatic water drains, then someone will need to be available to babysit the unit while it's operating.

Make sure you factor in filters and air testing into your operational budget.

Are there any regulations you're required to meet, such as air testing, and perhaps use of a containment system?

Do you expect to ever want/need to make Nitrox?

Do you have a suitable location for the whole setup? Ventilation (cooling) as well as a source of clean intake air. (You don't want to be doing this on a loading dock somewhere with trucks running right adjacent).

Finally, keep in mind, like many things the "Good, Fast, Cheap - Pick two" rule is going to apply. You probably want to figure out a budget and work backwards from there to see if you can get what you need, but plan for future expansion perhaps (such as adding a bank system).

 

[grantmac]

Since you are in an aquarium have you considered light surface supply with a bail out cylinder? Because then you are getting fills rarely (probably once a year) while also being a much safer system.

 

[michael Friesen]

Since you are in an aquarium have you considered light surface supply with a bail out cylinder? Because then you are getting fills rarely (probably once a year) while also being a much safer system.

Thanks for the suggestion,
we have looked into it in the past.

The configuration of our water bassins combined with the safety requirements of the Canadian Association of Underwater Sciences (our standards organization) aren't compatible with surface supply for our main dive tank. Two other bassins could be compatible, but seems silly to invest in a surface supply system for those two bassins which we only dive 20x a year in.

 

[michael Friesen]

got a fire department close by?

We do, actually our aquarium is a public service aquarium managed by the city, who also owns the fire department.

If you are suggesting that we ask them to fill up our tanks, well we asked already... Municipal bureaucracy makes that impossible.

 

[michael Friesen]

A Coltri unit via Nuvair is a good option, just got one from them recently.

MCH-6 is compact
MCH-11 is higher throughput, one fewer stage to maintain, possibly quieter. Single-phase 5.5HP motor can run on a 50-60amp 220V circuit (kinda like an EV charging circuit)

Allow at least 1-2 months for a new order

Thank you! The mch6 comes in a "silent. " Version which is basically just the same thing but in an acoustic box.

I will read up on them.

 

[michael Friesen]

Since you mention noise - consider adding a small cascade/bank to the setup - this will let you run the compressor at times when noise might not be as much of an issue, and also when general conditions (ambient temp) are more favorable (helps with filter life). Make sure the compressor is rated for the duty cycle required to fill the banks though...

Are you capable of self maintenance/repair? If not, then look for something with a local support network. A local vendor may also be able to source a good low-hour used model for you, especially if they support/maintain the local fire stations.

Other considerations - do you need High Pressure (3500+) fills? Who will be operating the unit? If you don't get automatic water drains, then someone will need to be available to babysit the unit while it's operating.

Make sure you factor in filters and air testing into your operational budget.

Are there any regulations you're required to meet, such as air testing, and perhaps use of a containment system?

Do you expect to ever want/need to make Nitrox?

Do you have a suitable location for the whole setup? Ventilation (cooling) as well as a source of clean intake air. (You don't want to be doing this on a loading dock somewhere with trucks running right adjacent).

Finally, keep in mind, like many things the "Good, Fast, Cheap - Pick two" rule is going to apply. You probably want to figure out a budget and work backwards from there to see if you can get what you need, but plan for future expansion perhaps (such as adding a bank system).

I am considering a cascade system, but really just for the sound.

I think I can do some basic maintenance (filter change) if I can't we have two industrial machine mechanics, but I appreciate your suggestion of finding the local guy, so if something does break, parts/help could be easier to get.

3 of my colleagues and I will probably be operators, babysitting might be doable, but will definitely look into automatic water drain.

I guess I don't need 3500+ psi, except if I do decide to do a cascade system.

I don't know the specifics of the regulations, air test for sure, never saw any dive stores near here have a containment system.

Will never have nitrox

We have some good spots, indoor with good ventilation, there are some skylights though, so might have direct sunlight on it.

I think we don't need fast, our highest air consumption is 15 bottles a week, and that happens like once a year, average being 8/week. If it's slow I guess I would prefer not to have to babysit it though. Quality is my #1, cheap is always good, but I am certain my budget isn't a concern.

 

[justinthedeeps]

You might not need bank cylinders but it is nice to have.

My ex-NOAA buddy has the MCH-6 at home and it is serving what you describe.

The MCH-11 runs at lower RPMs and can directly fill two steel HP80/100 cylinders to 250bar/3700psi (the warm equivalent of ~220-230 bar / ~3442psi) at once in like ~20 minutes (or less) using dual whips. It can be fitted with a factory-adjusted automatic pressure shutoff switch.

Whip checks might be a good bandaid to please your sense of damage control, or the safety inspector. They don't always work and it is a small hose, but a fully loose burst hose connection at the crimp could still possibly cause injuries.