Coil resistance. 1067Ω.
Rated coil voltage. 24V DC.
Coil voltage min. 18V DC.
Coil voltage max. 31.2V DC.
The maximum coil voltage is listed as 31.2 volts DC.
Maybe that is why the coil burned out?
Thanks for the updates on everything.
SPA heater, what would happen?
- Thread starter Hulaomr
- Start date
Rated coil voltage. 24V DC.
Coil voltage min. 18V DC.
Coil voltage max. 31.2V DC.
The maximum coil voltage is listed as 31.2 volts DC.
Maybe that is why the coil burned out?
Thanks for the updates on everything.
Note that I am not 100% sure about the relay driver part number, so I would not replace the relay driver unless you can find the exact part number or unless just replacing the relay does not work.
It's ok. I confirmed anyway. Please, be aware such 18 pin DIP IC is a microcontroller.
Ok, thanks.
You seem to be very skilled at working on this type of thing.
Hopefully, it will work correctly after the fixes.
Part number PIC16C622A-04I/P
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Can that be easily replaced?
Does it need to be programmed?
Could it be responsible for the high DC voltage to the relay?
Is part number ULN2803A a suitable replacement or no?
Yes, it could be easily replaced
Yes. That the difficult part
I don't think so
Definitely, not. Are two different things.
The PIC16 is the computer that manage everything on the FENWAL, the start sequence, the led status, etc...
@JamesW
I found a relay replacement locally and installed it a few minutes ago.
The voltage in the ignitor is now 120V (with a true RMS meter).
The heater start right away!!
Ok, thanks for the update.
Glad that you got it going.
The 15 Hz frequency is interesting.
I guess that that is how they convert 240 volts to 120 volts.
Glad that you got it going.
The 15 Hz frequency is interesting.
I guess that that is how they convert 240 volts to 120 volts.
@JamesW, a few findings:
Thanks again for your invaluable support!!
- According with a thermal camera, the temperature in the exhaust is around 111 C. It's normal?
- The heater is located in a room with 4 walls: 3 sides covered (hard wall) and 1 with bars (ventilation). I probably need to install a pipe for the exhaust, but during the test the smell is quite strong. I understand it can produce carbon monoxide (CO) which is dangerous but this strong smell could be the fact the heater has been never used (first time use)?
- The pressure gauge at the meter location is showing the pressure on the high pressure line (to the regulator heater). During operation is show a drop of ~1 PSI. It this normal? Could be the meter be the reason the pressure test on the heater shows a drop of ~6"wc?
Thanks again for your invaluable support!!
@JamesW
I made the following measurement for you. Using an oscilloscope and a high voltage differential probe, I measured 1) the 240Vac lines, and 2) the ignitor voltage.
I added all the features (measurements) to the screen for you.
When the heater is operating (connected to) in 240Vac, the IC MT1 (in purple box) is switching the input L1 to get 120Vrms in the ignitor. The picture diagram shows the L1 circuit route: a) red (110V direct) and b) purple (240V switching by MT1).
Exhaust Gas Temperature
While running, press and hold the On button to display the exhaust temperature (Older Models).The new models use the Menu to get the SFS.
Here is what the normal exhaust temperature should be:
- Below 250 degrees...very low
- 250 to 290 ..................low
- 290 to 350.................acceptable
- 350 to 480 ..................high
- Above 480...................error/shutdown.
If the exhaust gas temperature is higher than normal, water may bypass the heat exchanger through a broken bypass valve.
If you hold down the "pool on" button, it stays on 80, then flashes to 40, then back to 80, then the 80/40 reading and E05 indicate that the board is not getting a reading from the sensor. It's usually a bad sensor or damaged wires.
Pentair MasterTemp Heaters - Further Reading
www.troublefreepool.com
111 C is 232 F, which is low, but check the stack flue temperature from the control panel.
Heaters can have a smell on first startup.
For the venting, I would have to refer you to a qualified gas contractor as I do not know enough to give you a good answer.
Adding a Carbon Monoxide Detector might be a good idea to detect carbon monoxide at dangerous levels.
The 597FA regulator seems to be designed for Propane.
Is your heater Natural Gas or Propane?
Description: 597FA HP REGULATOR 3-15 PSIG-1/4 FNPT X 1/4 FNPT
Features / Benefits
Designed to reduce propane gas container pressure down to between 3 and 100 PSIG.
RegO 597FA/597FB/597FC/597FD Regulator - DMC Gas Equipment Ltd
RegO High Pressure Regulator 597F designed to reduce propane gas container pressure down to between 3 and 100 PSIG. Ideal for liquid or vapor service, they can be used in a variety of applications including salamander heaters, weed burning torches, fish cookers, tar pot heaters, and other...
dmc-gas.com
The 6" might be due to the wrong regulator or undersized pipe.
What is the heater BTU/Hr, Pipe Size and Pipe length?
Ok, thanks for that.
Since the ignitor is a resistive load, the frequency does not matter.
It would not work for a motor.
Another way to change voltages would be to use 2 igniters and put them in series for 240 volts and in parallel for 120 volts.
This can be done with a selector plug or switch.
That is how the blower can use either voltage.
The blower has 2 sets of windings and the voltage selector plugs changes the windings from series to parallel depending on the input voltage.
The heater is 400k BTU, The Pipe size and length is on the diagram below:Exhaust Gas Temperature
While running, press and hold the On button to display the exhaust temperature (Older Models).
The new models use the Menu to get the SFS.
Here is what the normal exhaust temperature should be:
Note: HD models can be up to 75 degrees higher. HD models use a cupro nickel exchanger, and the efficiency is slightly lower, resulting in less heat transfer and more waste heat.
- Below 250 degrees...very low
- 250 to 290 ..................low
- 290 to 350.................acceptable
- 350 to 480 ..................high
- Above 480...................error/shutdown.
If the exhaust gas temperature is higher than normal, water may bypass the heat exchanger through a broken bypass valve.
If you hold down the "pool on" button, it stays on 80, then flashes to 40, then back to 80, then the 80/40 reading and E05 indicate that the board is not getting a reading from the sensor. It's usually a bad sensor or damaged wires.
Pentair MasterTemp Heaters - Further Reading
111 C is 232 F, which is low, but check the stack flue temperature from the control panel.
Heaters can have a smell on first startup.
For the venting, I would have to refer you to a qualified gas contractor as I do not know enough to give you a good answer.
Adding a Carbon Monoxide Detector might be a good idea to detect carbon monoxide at dangerous levels.
The 597FA regulator seems to be designed for Propane.
Is your heater Natural Gas or Propane?
Description: 597FA HP REGULATOR 3-15 PSIG-1/4 FNPT X 1/4 FNPT
Features / Benefits
Designed to reduce propane gas container pressure down to between 3 and 100 PSIG.
View attachment 622157
RegO 597FA/597FB/597FC/597FD Regulator - DMC Gas Equipment Ltd
RegO High Pressure Regulator 597F designed to reduce propane gas container pressure down to between 3 and 100 PSIG. Ideal for liquid or vapor service, they can be used in a variety of applications including salamander heaters, weed burning torches, fish cookers, tar pot heaters, and other...dmc-gas.com
View attachment 622156
The 6" might be due to the wrong regulator or undersized pipe.
What is the heater BTU/Hr, Pipe Size and Pipe length?
400 cubic feet per hour (400,000 btu/hr) should result in about 0.4" w.c of pressure drop in 1" pipe.
If we use 30 feet as the Total Equivalent Length, then the expected pressure drop is about 0.6" w.c.
So, either way, the pressure drop is higher than expected.
Maybe the regulator is not rated for the capacity?
If we use 30 feet as the Total Equivalent Length, then the expected pressure drop is about 0.6" w.c.
So, either way, the pressure drop is higher than expected.
Maybe the regulator is not rated for the capacity?
What is the pressure in the 228 feet of 3/4 PEX pipe?
Is the 5 psi before or after the regulator?
Is the regulator near the heater rated for 400 cubic feet per hour?
Is the gas meter rated for 400 CFH or higher?
Is the 5 psi before or after the regulator?
Is the regulator near the heater rated for 400 cubic feet per hour?
Is the gas meter rated for 400 CFH or higher?
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You can check the amount of gas used by checking the meter and it should use 400 Cubic Feet per Hour or about 100 cubic feet per 15 minutes.
