magnahelix or duel port manometer

[oldguy2]

can you use a duel port manometer for setting up an hrv?? and checking a pressure switch?and can you use a magnehelix for checking a pressure switch

[Admin]

Both measure inches of water column.  A digital dual port manometer is the best choice, and will work on setting up HRVs.  Most magnehelix are fragile and require yearly calibration.  I use a TPI 620 for testing gas piping for leaks, gas pressures, static pressures, venting pressures and to balance HRVs.

[harshal]

Was reviewing the forum
interesting question came to me.I have been using dual port manometer to chk theanifold pressure but how to find the gas leak ?

[Admin]

The B149.1-10 Clause 6.22.3 was amended since the post above and removed manometer as a testing method.  I'm not sure why they amended it.  When I used a dual port manometer I found it could be affected by wind and using a single port manometer was more reliable.  Also you need to use tight fitting tubing so you don't leak gas where you connect it to the pressure test tee on the gas meter outlet fitting.  There may be a lock washer behind the test tee cap.  Make sure you remove that before connecting the manometer tubing to it or it may leak gas.  Make sure all gas appliance are off and open the supply valve at the gas meter.  Your manometer should read the supply pressure leaving the regulator.  Let the gas pipe fill up with gas and the manometer should stabilize.  Take note of that number (eg 7.67"wc).  Then turn the supply valve off at the gas meter.  Watch your manometer for a few minutes, and if the pressure starts dropping you may have a leak.

AMENDED - Clause 6.22.3
After an appliance(s) is connected, the new system shall be tested in the following manner:
(a) Before turning on the gas for the test, a check shall be made to ensure that any opening from which gas can escape is closed.
(b) Immediately after allowing the gas into the piping or tubing system, a test shall be made to determine that no gas is escaping by carefully watching the lowest volume test dial of the meter
(c) Where a meter is not provided, a working pressure isolated system (supply shut off) test shall be completed and the pressure shall be measured with either a pressure gauge or equivalent device calibrated to read in increments not greater than those specified in Clause 6.22.2(b), with the following exceptions:
(i) for a system where the working pressure is 0.5 psig (3.5 kPa) or less, the pressure gauge or equivalent device (e.g. a manometer) shall be calibrated to read in increments of not greater than 1 in w.c. (250 Pa); and
(ii) for a system where the working pressure exceeds 0.5 psig (3.5 kPa) but does not exceed 5 psig (35 kPa), the pressure gauge or equivalent device shall be calibrated to read in increments of not greater than 2 in w.c. of pressure (0.5 kPa); and
(iii) For this test the gas supply shall be shut off and the contained gas pressure shall be monitored for leakage indicated by a pressure drop.
(d) The test described in subsections (b) and (c) shall be of a 10 minute duration.
(e) Each appliance connection, valve, valve train, and system component shall be checked while under normal operating pressure with either a liquid solution or a leak-detection device to locate any source of a leak.
Removed manometer from 6.22.3(b).  – Dial test only on activation.  Added 6.22.3(c) to 6.22.3(d). – Test duration is 10 minutes.

Some inspectors use the older liquid filled U-Tube manometers and those seem to work well, but new installtions still require a pressure test and now a dial test at activation.

[harshal]

Thx for info.I think Enbridge follows same procedure but never knew before.thx for the info.