Mendota fv44i bowing?

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Mar 16, 2019
3
MD
We bought a Mendota fv44i gas insert in November, and recently noticed that the metal frame around the insert (I’m not sure what the proper name for this is) appears to be bowing, so that it’s visible even with the fireplace front on. This also seems to be making it a bit difficult to attach the front. See photo for what I’m talking about.

Is this normal? Is it a problem? We had a lot of trouble with the contractors who installed the unit so I’m not 100% confident they did this properly!

Thanks so much for any insight you can provide!

D6A799FB-7364-4627-B47A-0F0B0F27D23B.jpeg
 
That sucks. I've seen this same problem on different parts on different brands. Just using to cheap and lightweight of parts I think. Dont really know what the fix is.
 
https://mendotahearth.com/pdfs/manuals/2016 FV44i Installation and Operating Instructions - 0616.pdf

I'm presuming your concern is with the white appearing metal above the glass, is that correct?


Did you get the warranty information on page 51 of the manual above filled out when the fireplace was installed? Looks like that should have been done along with the appropriate tests to be sure that the unit isn't being overfired and thus getting too hot, which might be an explanation for the bowing you are observing.

I can't really identify the part you are concerned with from the parts illustrated circa pages 46 and so in the manual, nor can I really say what that part is doing based on the picture. But it seems unlikely that it should be bending like that, and since it is bending that implies that something is getting too hot. An overfired burner would be a likely explanation for that, which might imply that the main burner input gas pressure migh be too high and was not checked and adjusted when the fireplace was installed.

I would call the installer and ask them to come out and do the inspection required on the warranty form, and to check and set the main burner gas pressure in particular, and offer any explanations for the bowing they might care to do. Just bending it back so it's straight isn't an acceptabl;e repair, in my view, not unless they identify the reason why it was damaged.

You could hold their feet to the fire (so to speak) and ask them to replace the damaged part if you wish.

I would hold the contractor responsible first, the manufacturer second if you need help building a fire under the contractor (so to speak) to identify and correct the problem.

Mendota ought to be able to tell you which distributor sold the fireplace to your installer, and that distributor ought to help you get the installer motivated to fix the problem if they drag their feet, since they might refuse to sell product to someone doing a poor job of installing and backing equipment they sell. If you supply the model and serial number to Mendota, they ought to be able to tell you the chain of ownership from Mendota to the distributor to the installer to you.

Is there anything else that might suggest that the fireplace is getting too hot? Most fireplaces would have a limit switch that would turn the burner off if it overheats, and then back on again when it cools off. You might notice a pattern of on again off again burner operation if that were happening.
 
https://mendotahearth.com/pdfs/manuals/2016 FV44i Installation and Operating Instructions - 0616.pdf

I'm presuming your concern is with the white appearing metal above the glass, is that correct?

It is that metal piece above the glass. I also couldn't figure out what the part is called. It bows so that it is visible even when the fireplace front is attached, which wasn't the case when the fireplace was first installed.

Did you get the warranty information on page 51 of the manual above filled out when the fireplace was installed? Looks like that should have been done along with the appropriate tests to be sure that the unit isn't being overfired and thus getting too hot, which might be an explanation for the bowing you are observing.

I can't really identify the part you are concerned with from the parts illustrated circa pages 46 and so in the manual, nor can I really say what that part is doing based on the picture. But it seems unlikely that it should be bending like that, and since it is bending that implies that something is getting too hot. An overfired burner would be a likely explanation for that, which might imply that the main burner input gas pressure migh be too high and was not checked and adjusted when the fireplace was installed.

Of course these people did NOT do the tests in the manual. Wish we had realized at the time.

I would call the installer and ask them to come out and do the inspection required on the warranty form, and to check and set the main burner gas pressure in particular, and offer any explanations for the bowing they might care to do. Just bending it back so it's straight isn't an acceptabl;e repair, in my view, not unless they identify the reason why it was damaged.

You could hold their feet to the fire (so to speak) and ask them to replace the damaged part if you wish.

I would hold the contractor responsible first, the manufacturer second if you need help building a fire under the contractor (so to speak) to identify and correct the problem.

Mendota ought to be able to tell you which distributor sold the fireplace to your installer, and that distributor ought to help you get the installer motivated to fix the problem if they drag their feet, since they might refuse to sell product to someone doing a poor job of installing and backing equipment they sell. If you supply the model and serial number to Mendota, they ought to be able to tell you the chain of ownership from Mendota to the distributor to the installer to you.

Unfortunately the installer and the dealer are the same business... I am glad to hear this is worth bringing up though! I had hoped we'd have no reason to interact with them ever again, but I'm also glad to know I'm not imagining there is an issue or overreacting (they will almost certainly tell us one of those things).

Is there anything else that might suggest that the fireplace is getting too hot? Most fireplaces would have a limit switch that would turn the burner off if it overheats, and then back on again when it cools off. You might notice a pattern of on again off again burner operation if that were happening.

It doesn't turn on and off so I don't think it's to the point of overheating. It does get the house EXTREMELY hot, even on the lowest setting. We almost never use it above the lowest setting. But this is the first fireplace I've ever had, and I understand this one is relatively powerful, so I have no real point of reference there.

In any case thank you so much for your insight! We will be contacting the dealer/installer this week.
 
I don't know of these heat limit switches. Some bvent stoves have them in the hood. Some IPI log sets have them. Some bvent fireplaces have them. Some remote receivers have them... but I've never seen one in a DV fp or insert...
 
Wooduser what exactly to you mean by set the burner pressure?
 
Hello Millbilly,


I was surprised when you said direct vent fireplaces don't have over temperature limit switches, but when I went back and lookled through the manual of operating parts on page 44, no such limit switch is in evidence. So you are right.

Several places in the manual specify that the input gas pressure and the burner manifold pressure be tested, and the correct burner manifold pressure to be set is in the manual. Also the correct burner orifice sizes are listed in the manual. The BTU input to the burners is set by the size of the orifices and the manifold pressure. So since this fireplace MIGHT be operating at an unusually hot temperature, and since the menaual specifies that the burner manifold and burner orifice size be checked when the fireplace is installed, but this wasn't done, I'd say the customer might reasonably expect the dealer/installer to come out and check that the input is correct.

Also, if there is any sign of black soot in the fireplace, that would be a likely symptom of overfiring, and a condition that should be corrected should it exist.


Thank you Millbilly---- I'd never noticed the absence of high temperature limit switches in direct vent equipment before. You learn something every day, and that's IT for today!

Millbilly, can you identify the bent part in question? I can't really do that from the illustrations in the manual. It looks like there is a catch to release the glass and another going back to release the vent and combustion air pipe that might be related to that part, but I can't tell with any confidence.

Any other theories other than overheating that you might expect to be causing this? I suppose if the part is connected to the vent pipe or glass and is getting unusual strain, that might have caused the bend. Can't really tell though.
 
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Well you've got your input pressure and out put pressure. I'm at sea level so there's no elevation factors. So the only reason that a burner orifice should be changed is if the customer is on LPG and the unit was set up for NG. The actual regulator on the control valve of the appliance itself I've always considered a user function. Some units fire differently than others because of individual venting factors so I like to educate customers to not set their flame height so high that the flames lick the ceiling of the firebox. Personally I think that the ops issue is a manufacturing problem. I think these companies are making units with to flimsy of materials. I guess I'd call that a shroud? Or sheild? I dunno but it should be 3x as thick for the width it is and this is a problem with various manufacturers. Not only on shrouds outside of the firebox, but also panels inside of the firebox.
 
We bought a Mendota fv44i gas insert in November, and recently noticed that the metal frame around the insert (I’m not sure what the proper name for this is) appears to be bowing, so that it’s visible even with the fireplace front on. This also seems to be making it a bit difficult to attach the front. See photo for what I’m talking about.


Also, please check to be sure that nothing is blocking or impairing air flow into and out of the outdoor vent connector. That needs to be kept free of vegetation or other obstructions for correct operation of the fireplace.
 
Well you've got your input pressure and out put pressure. I'm at sea level so there's no elevation factors. So the only reason that a burner orifice should be changed is if the customer is on LPG and the unit was set up for NG. The actual regulator on the control valve of the appliance itself I've always considered a user function. Some units fire differently than others because of individual venting factors so I like to educate customers to not set their flame height so high that the flames lick the ceiling of the firebox. Personally I think that the ops issue is a manufacturing problem. I think these companies are making units with to flimsy of materials. I guess I'd call that a shroud? Or sheild? I dunno but it should be 3x as thick for the width it is and this is a problem with various manufacturers. Not only on shrouds outside of the firebox, but also panels inside of the firebox.
Wooduser I think you said you've been retired for a number of years? You'd be disappointed to see how flimsy some units are made now. Even from what I'd consider top tier manufacturers.
 
So the only reason that a burner orifice should be changed is if the customer is on LPG and the unit was set up for NG.


Quite true, but I have seen mistakes made by the factory. The worst example was a gas furnace with the burner orifices so small that the customer went YEARS with the house not warming up, and the heat exchanger getting filled with rust caused by condensation in the heat exchanger!

The heat exchanger was PLUGGED with rust! I had to get new burner orifices and clean the heat exchanger ----after that the customer had HEAT for the first time since he got the furnace new!

I also saw a unit heater with the wrong orifices in it. It was so overfired the heat exchanger cracked within a few weeks of it being installed.

I've seen a few other cases, but it's rare. Since this customer is reporting quite a hot fireplace with metal getting bent, suspecting overheating seems like something that should be checked, especially when it wasn't done when the equipment was installed as required by the manufacturer.

But it certainly could be a flimsy part, especially if something like the connection to the glass or vent is pulling on it. Hope they have to replace it as a reminder to do a better job if that's the problem. They should!
 
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Quite true, but I have seen mistakes made by the factory. The worst example was a gas furnace with the burner orifices so small that the customer went YEARS with the house not warming up, and the heat exchanger getting filled with rust caused by condensation in the heat exchanger!

The heat exchanger was PLUGGED with rust! I had to get new burner orifices and clean the heat exchanger ----after that the customer had HEAT for the first time since he got the furnace new!

I also saw a unit heater with the wrong orifices in it. It was so overfired the heat exchanger cracked within a few weeks of it being installed.

I've seen a few other cases, but it's rare. Since this customer is reporting quite a hot fireplace with metal getting bent, suspecting overheating seems like something that should be checked, especially when it wasn't done when the equipment was installed as required by the manufacturer.

But it certainly could be a flimsy part, especially if something like the connection to the glass or vent is pulling on it. Hope they have to replace it as a reminder to do a better job if that's the problem. They should!
Thanks wooduser. I have not experienced incorrect burner orifice from the factory and until today I would not have suspected that. Do you recall if those units actually had the wrong orifice, or if they were numbered correctly but diameter of orifice out of spec?
 
Do you recall if those units actually had the wrong orifice, or if they were numbered correctly but diameter of orifice out of spec?


They both had the wrong orifice. Again, a rare issue, but a possibility.

As an amusing aside, in the case of the underfired furnace, my boss had actually been out on a service call on that equipment a few years earlier, but had not caught the problem.

I never did tell him about it though!

Imagine what the guy at the factory would say---- "I put the blankety blank orifice that they give me in the blankety blank furnace. Am I responsible if they give me the wrong blankety blank orifice??"

Good question!

In this particular case though, the manufacturer requires the installer to check the orifice and the burner manifold pressure, but they didn't do it.

The manufacturer then requires the installer to fill out a certification that they did the required testing to be kept as a record by the manufacturer. So in this case, the manufacturer supposedly gets a receipt verifying that everything was OK. They just don't check to see if they actually get the receipt.

Perhaps we should be surprised that the RIGHT blankety blank orifice gets in the equipment as often as it does!
 
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Hi all - just wanted to give you an update! Turns out Millbilly was right and this is just part of the (bad?) design. Mendota said:

"This is the design of the insert and nothing is wrong. You will get a little sag/bow in the very center of the insert and this will not affect the operation of the insert of warranty of the insert. If needed the installer can shadow/paint the part you are seeing when surround is installed."

Kind of surprised but I guess there isn't anything we can do about it.
 
"This is the design of the insert and nothing is wrong. You will get a little sag/bow in the very center of the insert and this will not affect the operation of the insert of warranty of the insert.


Ummm. So they design a part poorly and then claim they have no responsibility for it?

What they should have done is apologized for their bad design, announced that they have a better designed part now in production, and announced that they are sending one to you at no charge,.