2005 Hot Spring Vanguard Heater Problem...

[doctauri]

I just bought a used 2005 Hot Spring Vanguard (VV) spa. It's in great shape, and according to the owner, they've not had any problems with it. I got it home and hooked it up, then filled it. First mistake, I just tossed the hose into the tub, so when I went to turn it on, there were no bubbles coming from the floor return. I used a hose and back flushed the system, blew out any air, and now get bubbles, but it will not heat. Jets work great, as does the light and the circulation pump, but no heat. No breakers are tripped, and it's not in summer mode (I've even turned summer mode on, then off again, hoping to reset it). I've reset the breakers about a hundred times, no change. Power light is on, but ready light never does. Temperature is set for 104 (though i've adjusted up and down), but water stays at 64. I can feel the water flowing through the tubes on the heater.

As I understand it, the potential source of the problem could be:

- 1. No power, or improperly wired power to heater

- 2. No water flow through the heater

- 3. Bad pressure switch (for sensing water flow through the heater)

- 4. Bad limit switches (for determining when to come on/off)

- 5. Bad heater

- 6. Bad heater control board

When I remove the cover on the IQ2020, I have a green light for "LIM OK", and a red light for "Heater On". The last light, "CONTROL UNPLUGGED" is not lit.

I've examined the heater PCB on the left (which the incoming power leads connect to, as well as the heater power), and find no visible signs of burning or blown components.

I test the power leads coming into the block (from the breakers), I get 123v & 125v across both legs, and 248v across the two legs together.

I check the terminals for the black and white leads from this board to the heater (after removing the heater leads), I get 4V on the black one, and 125v on the white. I'm not sure if this is right (as the black goes through some components first), or if this is the problem.

I checked the resistance between the black and white leads of the heater and get 9.8ohms

I have a PDR heater, which according to this, has no reset button.

http://www.teddybearpools.com/ask_the_bear/item/how_do_i_restart_my_heater.html

Excuse the length of this, it's as much about explaining the problem, as validating from the experts that I properly understand the heater sub-system.

Thanks!

[PreservedSwine]

I just bought a used 2005 Hot Spring Vanguard (VV) spa. It's in great shape, and according to the owner, they've not had any problems with it. I got it home and hooked it up, then filled it. First mistake, I just tossed the hose into the tub, so when I went to turn it on, there were no bubbles coming from the floor return. I used a hose and back flushed the system, blew out any air, and now get bubbles, but it will not heat. Jets work great, as does the light and the circulation pump, but no heat. No breakers are tripped, and it's not in summer mode (I've even turned summer mode on, then off again, hoping to reset it). I've reset the breakers about a hundred times, no change. Power light is on, but ready light never does. Temperature is set for 104 (though i've adjusted up and down), but water stays at 64. I can feel the water flowing through the tubes on the heater.

As I understand it, the potential source of the problem could be:

- 1. No power, or improperly wired power to heater

- 2. No water flow through the heater

- 3. Bad pressure switch (for sensing water flow through the heater)

- 4. Bad limit switches (for determining when to come on/off)

- 5. Bad heater

- 6. Bad heater control board

When I remove the cover on the IQ2020, I have a green light for "LIM OK", and a red light for "Heater On". The last light, "CONTROL UNPLUGGED" is not lit.

I've examined the heater PCB on the left (which the incoming power leads connect to, as well as the heater power), and find no visible signs of burning or blown components.

I test the power leads coming into the block (from the breakers), I get 123v & 125v across both legs, and 248v across the two legs together.

I check the terminals for the black and white leads from this board to the heater (after removing the heater leads), I get 4V on the black one, and 125v on the white. I'm not sure if this is right (as the black goes through some components first), or if this is the problem.

I checked the resistance between the black and white leads of the heater and get 9.8ohms

I have a PDR heater, which according to this, has no reset button.

http://www.teddybear..._my_heater.html

Excuse the length of this, it's as much about explaining the problem, as validating from the experts that I properly understand the heater sub-system.

Thanks!

When you're testing for power at the block, are you testing between terminals 2 and 4, or 1 and 3, or you tested both?

If both (1 and 3 = 240; 2 and 4 =240) are good, you likely have a bad heater PCB (part number 74618)

To confirm- test for voltage at heater leads on the heater PCB in the IQ2020. You shouldn't get 240v. OHM the heater out- either ~7.2 or ~10.5 OHMS (4 or 6KW) if the element is good.

[doctauri]

When you're testing for power at the block, are you testing between terminals 2 and 4, or 1 and 3, or you tested both?

If both (1 and 3 = 240; 2 and 4 =240) are good, you likely have a bad heater PCB (part number 74618)

To confirm- test for voltage at heater leads on the heater PCB in the IQ2020. You shouldn't get 240v. OHM the heater out- either ~7.2 or ~10.5 OHMS (4 or 6KW) if the element is good.

Thanks for the reply.

- When testing 2&4 and 1&3 on the incoming power block, I get 240v.

- When I disconnect the heater and put the meter against the white and black leads for the heater, I get 9.8 ohms.

- With the heater disconnected, if I test the voltage where the heater attaches on the PCB, I get 6v on the black connection point, 123v on the white, and 28.3 across the two.

- If I connect the heater, and test again, I get only millivolts across the two...

I'm assuming this means a bad heater control board?

Thanks again!

[doctauri]

The more I think about this, the more I wonder if it's not an indication of a bad heater control board, could the fact that it has no voltage across the two simply mean that it hasn't decided to activate the heater?

Thanks.

[PreservedSwine]

When you're testing for power at the block, are you testing between terminals 2 and 4, or 1 and 3, or you tested both?

If both (1 and 3 = 240; 2 and 4 =240) are good, you likely have a bad heater PCB (part number 74618)

To confirm- test for voltage at heater leads on the heater PCB in the IQ2020. You shouldn't get 240v. OHM the heater out- either ~7.2 or ~10.5 OHMS (4 or 6KW) if the element is good.

Thanks for the reply.

- When testing 2&4 and 1&3 on the incoming power block, I get 240v.

- When I disconnect the heater and put the meter against the white and black leads for the heater, I get 9.8 ohms.

- With the heater disconnected, if I test the voltage where the heater attaches on the PCB, I get 6v on the black connection point, 123v on the white, and 28.3 across the two.

- If I connect the heater, and test again, I get only millivolts across the two...

I'm assuming this means a bad heater control board?

Thanks again!

yep.

Quick and easy.

[doctauri]

A few more questions...

1. I'm assuming that, when the heater is activated, this should be 240v when testing across the two heater connection points (black and white)?

2. Does the "heater on" light mean that it's attempting to start the heater, therefore, it should be 240v across these two points (and if this light is off [which I've not seen yet], it's at temperature, and I shouldn't get anything across them)?

Thanks again, I appreciate the help!

Also... Is there any way to hotwire the heater (bypass the control logic) to prove it's ok?

[PreservedSwine]

A few more questions...

1. I'm assuming that, when the heater is activated, this should be 240v when testing across the two heater connection points (black and white)?

2. Does the "heater on" light mean that it's attempting to start the heater, therefore, it should be 240v across these two points (and if this light is off [which I've not seen yet], it's at temperature, and I shouldn't get anything across them)?

Thanks again, I appreciate the help!

Also... Is there any way to hotwire the heater (bypass the control logic) to prove it's ok?

The OHM test across the elements has determined the element will heat fine once it's energized. (It doesn't test for current leakage- but that's a whole other can of worms that you're currently not experiencing any symptoms)

And yes, you should be getting 240 across the two points of the heater PCB where the heater leads connect.

The "heater on" led on the IQ202o means the IQ2020 is sending coil voltage to the heater relays located on the heater PCB- but one or more of the relays or traces are damaged. The issue is NOT on the IQ2020 side, but on the heater PCB side of the control box.

Your issue is a common for that era. Be careful when replacing- the new PCB is slightly different, but comes with very clear instructions. On the plus side- the new one won't fail.

[doctauri]

Thanks a lot for the help, I appreciate it. New board is on order, I'll status back once it's installed!

On a side note, and just for future reference, how do you test if the pressure switch, and the thermistors are good?

Thanks!

[PreservedSwine]

Thanks a lot for the help, I appreciate it. New board is on order, I'll status back once it's installed!

On a side note, and just for future reference, how do you test if the pressure switch, and the thermistors are good?

Thanks!

The tub does this for you- if the control-thermistor is out of range, the green "ready" light will flash. If the flow switch isn't working- both the red "power" and green "ready" lights on the display will flash.

If you really want to see what the control thermistor is reading- turn off the power, and move a mini-program jumper in the IQ2020 "jump" jp10, and turn the power back on. Now- after you set the temp, wait a few more seconds, and it will display the actual temp.

[doctauri]

Update: I ordered a new heater control board and replaced it, works like a charm. Thank you so much for all of your help and advice, I really appreciate it!

Tony