Just to be safe, I didn't run the heater besides that first time when the plumber tested it
Centerpoint called me this morning and I was glad that I had done a bunch of research. Instead of just telling them to upgrade my service, I explained all the equipment that I have and asked if they have to increase the line pressure to 2psi or if they also have larger volume meters at the existing low household pressure (0.25 psi). She then told me that upgrading the meter only for more volume at the current pressure is completely free of charge.
They only charge $350 when they have to change the meter to 2psi pressure and put in regulators further downstream to bring the pressure back to the typical 7" wc (=0.25 psi) the appliances use. Since the line from my meter to the gas heater is only 10ft and the heater is already running with the current meter, they said it will probably be enough to only switch the meter for more volume without increasing the pressure.
Apparently the reason why sometimes higher pressure is required is when the meter is far from the pool heater and the plumber does not want to put in a large diameter gas line. Instead of putting in the huge diameter gas line, they upgrade the pressure at the meter. Then they can continue that high pressure underground through a small diameter gas line all the way to the pool heater and reduce the pressure again with a regulator right in front of the pool heater.
Does that sound right?
