Field Controls OVD Control

skybolt_1

Piggybacking on my earlier thread regarding efficiency testing on my Beckett AFG to address sooting, I have noticed after the boiler shuts down the Field Controls OVD does not close. Apparently I got lucky enough for it to die in the open position and thus not leave me in a no-heat situation. This is the second motor on the OVD to die in the past two years, which unfortunately tracks with what I've read of others' experiences with these units.
I did a bit of amateur electrical testing and confirmed - same as with the first unit - that the motor was fine but the controller had died. I reached out to Field Controls through their online form asking whether the control board could be purchased (hey, it has a part number on the board itself!) and got the following back:
The control board is not a replacement part for the OVD. If this is the second time it has burnt out, it may be a wiring issue. I’ve copied Tech Support for more help.
Hmm. OK, what does tech support have to say?
We do offer a replacement controller for the OVD units. The part number for the controller would be 46564000. If the circuit board is burning out prematurely the installing contractor needs to make sure the OVD is properly wired per the installation instructions and that the system is not receiving any power surges when operating.
Power surges? I have a whole house surge protector installed.To this, they respond:
We do not have issues with the OVD units when connected to oil fired boilers. We would suggest that your installing contractor replace the controller for the OVD which we will authorize a warranty replacement for that controller through his wholesale distributor. The replacement controller when installed we would suggest that they check all the connections to make sure they are properly secured and have them check the voltage to the circuit board on the OVD when the appliance is operating to verify that there is no variance in the voltage to the circuit board. They should also check to make sure that the gate will spin freely though the pipe and that there is no restriction or binding of the gate through the pipe.
To me, this sounds an awful like a CYA response. The OVD is wired exactly as shown on page 12 of FC's installation guide to a HydroStat 3250 Plus. It works, as advertised, until it doesn't. Not sure what kind of "voltage variances" could be occurring here.
Any ideas?

EdTheHeaterMan

As a rep for the fields control, I would say that our controls are superior to all other options and you problem is rare because we are perfect.

As the installing contractor, I would say that we installed the parts according to the manufacturers instructions and we never make mistakes so the problem must be surges.

As the manufacturer of your whole house surge protector, I would say, our product is the best in the industry and therefore the installer and manufacturer of the ODV must have a product that is inferior or the installer has inferior workmanship issues.

As for me being none of the above, I would really evaluate the savings the ODV provides and think about the real cost or savings based on the poor performance of the ODV.

This comment probably does not help at all, but that is the American Way!

Is it at all possible that the position of the motor in relationship to the heating appliance and the vent connector pipe is such that the motor is getting overheated? I have noticed some flue collector boxes can get quite hot and if the motor is in close proximity to that heat, electronic innerds can fail (Innerds is a technical term)

skybolt_1

I love the multiple viewpoints in this comment! LOL.

The savings is hard to quantify. I do notice, with my barometric damper newly adjusted, that it is remaining open after the furnace shuts off and just watching all the heat go up is annoying.

I do not believe that the position of the OVD is a problem. It's not "over" any heat sources or exposed to any radiant heat other than what it was presumably designed for being attached to the flue.

jesmed1

I looked into installing these on our boilers and read one review where a user found that a particular capacitor on the control board was failing. He replaced it with a better capacitor and that solved the problem. I think the review with his photos and description of the capacitor issue is on the supply house.com website. You may be able to fix your control board in the same way.

skybolt_1

jesmed1 said:

I looked into installing these on our boilers and read one review where a user found that a particular capacitor on the control board was failing. He replaced it with a better capacitor and that solved the problem. I think the review with his photos and description of the capacitor issue is on the supply house.com website. You may be able to fix your control board in the same way.

WOW. This is why I love this place. Thank you for the heads up. I found posts referencing the person who first found it and just ordered a new capacitor + a spare from Digikey. $9.16 vs. over $150 for the entire unit is worth a dice role. I will give this a shot and if successful will post a report here so that the fix can live in more than once place.

skybolt_1

Update: Unfortunately, the new capacitor didn't change things at all. Bummer. Guess I will think about buying the replacement unit. Thanks again for the suggestion!

Jamie Hall

Personally, I do not like -- ad would not install -- a motorized damper. Yes, some heat does go up the flue. How much? Hard to quantify. On the other hand, they do fail -- regularly -- and the resulting no heat situation can, unless it's caught and can be remedied quickly can be very costly indeed. Not to mention annoying.

And all that was with older simpler units, which had no electronic controls other than a limit switch...

On the surge protector, however. A whole house surge protector sounds like a wonderful gadget. Install one and you have no worries. Um... not so much. If it is just a surge protector, and most of them are, it will do nothing to protect your house (and sensitive electronics inside) from reasonable over voltage or under voltage spikes, although it may help is the power line is hit by lightning, or in some types of power line failures.

jesmed1

skybolt_1 said:

Update: Unfortunately, the new capacitor didn't change things at all. Bummer. Guess I will think about buying the replacement unit. Thanks again for the suggestion!

Sorry to hear that. Good luck with the replacement.

tlj000

That's it I'm done with these. Mine failed today. 2nd one since 2019. Lucky for me I was home and it wasn't very cold out. Quick fix to bypass it.

Steamhead

I'm using one of these dampers and haven't had a problem in the two years it's been installed, for what that's worth.

I do remember that when dampers for gas appliances first came out, they weren't that reliable, and except for Flair and Effikal (the latter is now owned by Field) you couldn't get replacement motor assemblies, so a lot of these were bypassed when they broke. Flair also made dampers for oil-fired units.

You did check to make sure the inside of the damper was clean, so the blade wasn't getting stuck, right?

skybolt_1

Yeah I ended up throwing in the towel on the damper. Had it bypassed for a while but then something else failed in the control board and I woke up to a no-heat situation.  Tore out the entire flue assembly and put in a new pipe section sans damper.