Air Pressure Test for Inspection Question

[dogwood]

I've finally got my boiler plumbing all done. The local inspector now wants me to fill the system with air at 60 psi for inspection purposes. Couldn't that pressure mess with or screw up some of the elements of the system such as the expansion tanks, the pressure relief valves, the automatic air vents, the backflow preventer and the pressure regulator valve on the make-up/feed water line, and I don't know what else.

What do you recommend? Should I be disconnecting, plugging or valving off some or all of these items for the test? Any advice would be appreciated? Some of you must have had practical experience with this.

Here's an exact list of the items I'm most concerned about:

Extrol Expansion Tanks, SX-30V and SX-160V
Watts Automatic Air Vents, Series FV-4M1
Watts 0039QT 1/2 " Reduced Pressure Zone Assembly Backflow Preventer
Watts Feed Water Pressure Regulator Valve Series 1156F (comes set to 15 lbs)
A couple of standard 30 psi pressure relief valves

I have yet to do the final connection between the make-up/feed water line and our home's water supply. I thought I should air pressure test the system first before connecting the feed line. I'll probably have to connect that up too prior to inspection. I guess I should shut off the valve on the feed water line for the pressure test, as 60 psi is greater than the 50 psi of our well-fed water supply.

My boiler is a Solo Innova 50 and I've a 1000 gallons of storage. I assume the boiler, the w/a heat exchanger in the furnace plenum, and the Bell and Gosset Type Low Pressure BPX Brazed Plate flat plate hx to the DHW supply can handle 60 psi.

Thanks for your help.

Mike

 

[ewdudley]

Similar thing happened to me years ago when I took my driver's test. Tester told me I had basically passed the test, but before signing off he wanted me to run a while at 110 mph just to make sure I could handle 55 mph reliably.

 

[Fred61]

Along with all the hardware you mentioned you also have a boiler. I would dispute the order (or recommendation) with the inspector. Perhaps ask him about his bacground in boiler piping.

 

[maple1]

Yes - there must be a tag on your boiler with a max pressure on it. I'm thinking it'll be a lot lower than 60psi.

 

[kopeck]

The other thing is you would have to disable your blow off valve some how since it's going to open up at 30 PSI.

I tested mine at 28ish (the gauges varied a bit, so say 25+ pounds), I figured if it held that much air it would hold 18 PSI of water.

60 PSI seems excessive.

K

 

[maple1]

BTW - is it a norm to have an inspector involved in the first place? That wasn't even on my radar.

Is this an insurance guy? Or a building permit guy? Or ?

 

[kopeck]

BTW - is it a norm to have an inspector involved in the first place? That wasn't even on my radar.

Is this an insurance guy? Or a building permit guy? Or ?

I'm sure it's a local thing. Where I live the only thing they inspect is your plumbing (Domestic Water & Drain).

K

 

[ozzie88]

The other thing is you would have to disable your blow off valve some how since it's going to open up at 30 PSI.

I tested mine at 28ish (the gauges varied a bit, so say 25+ pounds), I figured if it held that much air it would hold 18 PSI of water.

60 PSI seems excessive.

K

I agree 60lb seem to much i would be asking abot his reason why so hi, And call the boiler maker ask them if it ok same with other itoms. Have him show you in some code book that 60lb, has to be used or if it just his way he wants it done???

 

[ozzie88]

The other thing is you would have to disable your blow off valve some how since it's going to open up at 30 PSI.

I tested mine at 28ish (the gauges varied a bit, so say 25+ pounds), I figured if it held that much air it would hold 18 PSI of water.

60 PSI seems excessive.

K

I agree 60lb seem to much i would be asking abot his reason why so hi, And call the boiler maker ask them if it ok same with other itoms. Have him show you in some code book that 60lb, has to be used or if it just his way he wants it done???

 

[dogwood]

I'll give the building department a call and find out what's up. I've never put in a boiler before so thought this procedure was the norm. Maple1, this is a building department inspector. He was real pleasant when he did my rough carpentry inspection and was very intersted in the wood gasifier. Even said he and his Dad were going to build one of those Russian fireplaces. I'll look at the Solo Innova's tag and see if it lists a max pressure. Thanks for suggesting that.

Eliot, should I disconnect all the items I listed if I have to do the 60 psi? I really don't want to screw up the expansion tanks and the rest. Maybe he made a mistake. And I bet you could still handle the 110 mph just fine Eliot. Thanks for all the replies.

Mike

 

[EffectaBoilerUser (USA)]

The 60 psi for a boiler system pressure check seems excessive.

I would have no problem with testing the storage tanks to 60 psi (assuming they are propane tanks which are good till 250 psi or so).

However, I see no reason to test everything else in the system to more than 30 psi. After all, that is what the pressure relief valve will go off at.

 

[ewdudley]

I'll give the building department a call and find out what's up. I've never put in a boiler before so thought this procedure was the norm. Maple1, this is a building department inspector, he was real pleasant when he did my rough carpentry inspection and was very intersted in the wood gasifier. I'll look at the Solo Innova's tag and see if it lists a max pressure. Thanks for suggesting that.

Eliot, should I disconnect all the items I listed if I have to do the 60 psi? I really don't want to screw up the expansion tanks and the rest. Maybe he made a mistake. And I bet you could still handle the 110 mph just fine Eliot.

110? Sure for a maybe a couple hours at a time in an Audi with V-rated tires, but as much as I'm fond of my little Focus I'm not going to cruise at those speeds with the tires it has. Likewise as has been pointed out, if the boiler is rated for 30 psi or 36 psi or whatever, then what? It's not the inspector's system to play around with.

My buddy the boiler man says they use cold water at elevated pressures to find leaks in a new system. He says hot fixtures are less likely to leak. Air would work, but if something big blows it could take out a wall with it. If a tank full of water goes you've got water all over the place.

Hopefully your expansion tanks are already isolated with valves, even so I'd want to crack a union on the tank side to make sure pressure didn't leak past a valve and over-stretch the bladder. And as you suggest, the pressure reliefs and air vents would have to be removed and replaced with plugs. I don't know what the feed water devices would do with high back pressure, but can't see any reason to find out.

 

[dogwood]

Thanks Eliot. I am going to disconnect the expansion tanks at the unions as you suggest.

Mike

 

[BoilerHouse]

It is very unusual to pressure test anything, boilers included, with air. Always use water. (Hence the name - Hydrostatic test). And any real boiler inspector would know this.

 

[dogwood]

I'm going to go down to the inspector's office and check into this. He did have me buy a shrader valve, like you use to fill tires with air, to put air into the system. I am definitely feeling something is wrong here now. Thanks for your input BoilerHouse.

Mike

 

[BoilerMan]

I always air test any type of hydronic system with around 25psi, but that is for my own purposes. It's much easier to solder a leaking joint in copper before there is any water in the system. As EWD said the boiler will be rated to 30 or 36psi, that rating should NEVER gone over, the inspector is off his rocker if he wants you to double the boiler's rating.

FWIW, I leave the 25 or so psi in the boiler for at least 24 hours, I've had small leaks that took at least that long to show up, especially if there are large storage tanks involved. Longer is better, and soap and water in that old windex bottle are your friend.

TS

 

[heaterman]

If your resident inspector is demanding the air test to determine the safety/integrity of your system he is off his rocker. An air test (minimal pressure) should only be used to locate leaks in your piping etc. A true test of the systems structural integrity is always a hydrostatic test. ASME spec is 1.5 times the boilers rated relief pressure. In the case of nearly all residential boilers this would be 45PSI.
Air should never be used to determine the integrity or failure point of a pressure vessel such as a boiler for obvious reasons.

 

[dogwood]

Taylor, I was planning on a 20-25psi air test for leaks as I've read about. Heaterman, thanks for your, and Boilerman's too, info on hydrostatic tests. I'll be back home Thursday and will check in with the inspector. Maybe I misunderstood something. Seemed pretty clear at the time though.

Mike