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Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 8001
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have a Quietside DPW-199a used for heat and domestic HW.

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I have a Quietside DPW-199a used for heat and domestic HW. It was installed 2 months ago. A week after installation I started getting A6 Failure to Ignite errors - a couple of times/week. The manufacturer rep looked at it and said it was installed correctly, however it needed a larger regulator at the meter. This was done by the gas company and the A6 errors stopped for a month. However, now they're back. He's been back a few times - tweaked this and that but no progress. After it fails, just toggling the power starts it right back up. At this point Quietside isn't being very responsive. Current thinking is its the main board but that's just a guess.

Phil :

All work to be done by licensed professional. WE KEEP GOING UNTIL YOU HAVE THE INFORMATION YOU NEED, I come and go. This is step ONE.

Phil :

Hello

Phil :

Failure to ignite can be caused by any of the following or a combination of these.

Phil :

- Gas pressure a bit too high or too low

Phil :

- Pilot/ main burner flame not impinging on the flame sensor rod directly enough.

Phil :

- Lose wire connections in the control circuit

Phil :

With a new boiler, and new parts, it is most likely that the gas pressure too high causing the burner flame to lift off of the burner head at times...when that happens the flame sensor will not be able to its job of leaking electrical current back through the flame to ground...and will shut the gas valve off and lock the system out.

Phil :

OR... the gas pressure is set a bit too low, and the burner flame is not impinging reliably on the flame sensor rod..so it fails to detect the flame occasionally and shuts the gas valve down.

Phil :

but since this was already apparently known and these pressures adjusted so frequently and you still have the problem... we must look at the electrical issues.

Phil :

This could be a control card but thats not a common control card failure mode. stray electrical currents in the house neutral or ground wiring can cause such anomalies by interfering with the systems electronics.

Phil :

Intermittent problems like this can be exceedingly hard to detect.

Phil :

Sometimes all that can be done is to wait until it gets worse, and the problem more obvious or something fails entirely... then the fault is detectable.

Phil :

Sometimes bending the flame detector rod a bit so it is more directly in the burner flame will solve the problem.

Phil :

Phil

Customer:

Phil,

Customer:

This unit attempts to refire 3 times before it gives the error code. However, if I simply toggle the power it will start right up. I've done this immediately after an A6 code. Any ideas why it would start then but not automatically?

Phil :

Hello again

Phil :

The three attempts to fire before lock out is built into the controls.

Phil :

when you toggle it on and off you are simply rebooting the controls before they have a chance to try the ignition three times and lock out

Phil :

You might ask why it starts right up after you toggle it? Good question

Customer:

I meant I toggled the power after the three attempts - then it started up.

Phil :

toggling it resets the controls

Phil :

why it then starts on the first try is a good question.

Customer:

So you think it's a control issue?

Phil :

it gets into the vagaries of the electronics

Phil :

it is an electronics controls issue

Phil :

but since the flame is part of of the electronics circuit itself, its also a flame issue

Customer:

Some more info: it typically fails when calling for domestic HW. IS that a clue?

Phil :

it could be that toggling it, allows the control card to shut down long enough to bleed electrons off of its micro circuits so they behave differently when the card is powered back up again

Phil :

its something along those lines

Phil :

if it fails when calling of DHW do you have to toggle it to get it to fire.

Customer:

OK, thanks. I think you're right in that I'll have to wait until it gets worse before it gets better.

Customer:

Same as I mentioned. It tries 3 times, gives an A6, then I toggle the power and it starts.

Phil :

The time to press this issue is while its still in warranty, Now is the time to demand a fix, or something like a five year parts and labor extended warranty

Customer:

Roger that.

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