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NG Regulator Placement for Fireplace

bacon Member Posts: 5
I am installing a new gas fireplace into a basement. I have a pounds to inches regulator that is in a mechanical closet that is about 30ft away. I was having trouble getting the proper pressure output at the fireplace and Maxitrol is telling me the regulator has to be ~3ft away from the appliance. City inspector tells me I cant put the regulator in the fireplace chase/surround because it has a vent limiter on it. Any ideas on how or where I should place the regulator for this thing?

Service is a 2psi line and the fireplace needs 5-10in-wc entering the manifold.

Thanks for any help!


  • ratio
    ratio Member Posts: 3,336
    Vent the regulator outside? I don't recall if there is a restriction on the length of a vent other than common sense, as long as the size isn't reduced.

    Is there a reason the gas line from the regulator can't be sized properly for the necessary flow rate? Gas lines sized for maximum pressure drop have always bit me on the hiney, in this very way.

  • bob_46
    bob_46 Member Posts: 813
    What size pipe do you have between the regulator and the fireplace ?
  • bacon
    bacon Member Posts: 5
    Sorry, I guess I didnt explain that well enough. The regulator was not locking up and was delivering a full 2psi to my fireplace instead of regulating it down to 8in like it was supposed to. The line between the fireplace and regulator is 3/4" to support this fireplace and a future one upstairs - it was sized for flow and there is plenty.

    The input from the guy at Maxitrol didnt make sense to me since dual pressure systems are constructed daily with a regulator before a manifold which distributes to various appliances. In that case, the regulator is nowhere near the appliances and they work just fine.

    I backed the adjustment screw out as far as I could last night and then turned it back in before turning the gas back on. I now have exactly 8in of pressure at the fireplace. Im not sure what happened, but it seems the regulator was stuck open for some reason. I'll have to monitor to see if it was a fluke or not.
  • captainco
    captainco Member Posts: 737
    I assume you are using a Maxitrol 325 regulator, which is a lock up type. If you were feeding 2 psi to the fireplace gas valve there could be another serious problem. The diaphragm in normal gas valves has a burst pressure of 1#, which means it is possible the fireplace valve could now leak. So far you have been lucky but if the valve doesn't regulate again it can push right through the fireplace gas valve and light up the neighborhood. This is nothing to fool around with. If the vent on the regulator is restricted or plugged this will cause a problem.
  • bacon
    bacon Member Posts: 5
    The appliance line that runs from the shutoff to the fireplace manifold has an overflow check valve in it. If the regulator were to stick open and damage the fireplace valve, this should shut and prevent all flow.
  • ratio
    ratio Member Posts: 3,336
    That makes more sense now. I was picturing a piece of 3/8 CSST in my mind...

    In any case, 2 lbs on a gas valve is bad news. That's well outside the operating parameters of most valves, I've condemned valves for that very reason. I'm quite sure that if your call the mfgr, they'll tell you the valve must be replaced. If it were my fireplace, though, I might just test it for leakthrough & then try it out.

    The gas valve aside, a bigger question in my mind is what was going on with the regulator. I would probably replace that, unless the supplier or mfgr could convince me that was normal...in which case I'd switch suppliers or brands. The whole, complete, & only job of a regulator is to maintain the outlet pressure no higher than its setpoint, if it fails at that even once I'm done with it, lack of confidence. Too many ways for gas to go south.

  • bacon
    bacon Member Posts: 5
    He said I could have turned valve on too quickly which prevented the regulator from locking up...does that make any sense? It didnt to me, but it even says in the instructions to open the supply valve SLOWLY (which I failed to do the first time around).

    As far as the fireplace valve, I think it's fine. It has two solenoids in it for pilot and burner, and I think they are both closed until power is applied. Everything was off when I was trying to establish manifold supply pressure. After I got the 8in I wanted, I powered it up and I have 0 at the burner. I suspect this is because the ignition module will not allow the burner solenoid to open until after it detects pilot ignition. I havent purged the air from the line yet, but plan to do so tonight. I'll know quickly if the valve has been damaged or not if I get anything other than ~3.5in at the manifold outlet.

    Thanks for the replies.
  • bacon
    bacon Member Posts: 5
    Just an update - I talked to Dexen, the fireplace valve mfg yesterday and they said 2psi shouldnt hurt the valve, but they wouldnt run it on 2psi (obviously).

    I purged all the air out of the line last night and everything fired up just perfect. The manifold outlet pressure (once the solenoid opened) was dead on at 3.5in too.

    I guess I'll monitor and see what happens.

    Thanks again