Hey guys. Looking for some suggestions on how to stop my newly installed Raypak Avia from howling as soon as the burners kick on. I've read many other posts complaining of the same thing. Here are things I've checked:
Gas pressure is good. 1" line riser out of the ground then 3/4" line into heater. Pressure is 7"WC upstream no load and 6"WC on load. Seems fine. Heater specs show this should be between 4"WC and 10.5"WC.
Unitherm governor. I've removed it and placed it in hot water above 120F. It started opening slowly around 130F and fully opened around 140F. Seems good.
Internal automatic bypass valve. I opened up the heaters header and inspected the valve. I was able to depress the plunger with my finger no problem. Doesn't seem stuck open. Seems good.
Flow rate through heat exchanger. This is the part I'm confused about. Heater specifies it needs between 40gpm and 100gpm to work. The heater estimates flow through the exchanger and it reads 12gpm. So I closed my manual bypass valve before the heater to force all water into the heater and now the heater throws a high flow error. This tells me I need to open the manual bypass valve again, however the estimated flow rate never goes over 15gpm and the heater keep howling. I'm wondering if this has anything to do with the fact my plumbing is 1.5" and the heater inlets are 2". All Raypak heaters come standard with only 2" inlets so that's bizarre.
I was able to quiet the howling mostly by lowering the gas pressure. However if I lower the pressure to quiet the howling completely, the heater will run but won't ignite next run. Gas pressure is too low. So I'm stuck with a howling heater.
On the plus side it appears to be working very well. Water temp difference between in and out of the hx is about 40F so it heats my pool fairly fast.
I've had a certified Raypak tech out to have a look but I wasn't impressed. He seems to not be very knowledgeable on how to fix it. Actually left my heater inoperable twice. Lowering gas pressure too much or blaming it on a plugged filter.
I also spoke to a Raypak technician on the phone which didn't lead to anything. He seemed to think the heater HAD to have 2" plumbing going to it. I find that hard to believe since anyone with 1.5" plumbing can't buy a Raypak now? All they sell now are heaters with 2" inlets.
Any suggestions?
Gas pressure is good. 1" line riser out of the ground then 3/4" line into heater. Pressure is 7"WC upstream no load and 6"WC on load. Seems fine. Heater specs show this should be between 4"WC and 10.5"WC.
Unitherm governor. I've removed it and placed it in hot water above 120F. It started opening slowly around 130F and fully opened around 140F. Seems good.
Internal automatic bypass valve. I opened up the heaters header and inspected the valve. I was able to depress the plunger with my finger no problem. Doesn't seem stuck open. Seems good.
Flow rate through heat exchanger. This is the part I'm confused about. Heater specifies it needs between 40gpm and 100gpm to work. The heater estimates flow through the exchanger and it reads 12gpm. So I closed my manual bypass valve before the heater to force all water into the heater and now the heater throws a high flow error. This tells me I need to open the manual bypass valve again, however the estimated flow rate never goes over 15gpm and the heater keep howling. I'm wondering if this has anything to do with the fact my plumbing is 1.5" and the heater inlets are 2". All Raypak heaters come standard with only 2" inlets so that's bizarre.
I was able to quiet the howling mostly by lowering the gas pressure. However if I lower the pressure to quiet the howling completely, the heater will run but won't ignite next run. Gas pressure is too low. So I'm stuck with a howling heater.
On the plus side it appears to be working very well. Water temp difference between in and out of the hx is about 40F so it heats my pool fairly fast.
I've had a certified Raypak tech out to have a look but I wasn't impressed. He seems to not be very knowledgeable on how to fix it. Actually left my heater inoperable twice. Lowering gas pressure too much or blaming it on a plugged filter.
I also spoke to a Raypak technician on the phone which didn't lead to anything. He seemed to think the heater HAD to have 2" plumbing going to it. I find that hard to believe since anyone with 1.5" plumbing can't buy a Raypak now? All they sell now are heaters with 2" inlets.
Any suggestions?