Change glass for gas conversion?

[ClintFlintFromBedrock]

I want to convert a wood burning fireplace to gas (propane). I heard I may need ceramic glass. Do I need to change the glass in my doors to ceramic?

 

[wooduser]

There are two ways to do what you want to do:

1. A set of gas logs uses your existing fireplace and flue, and a gas burner sits in the fireplace to burn the gas. The chimney damper needs to be wired open so it cannot be closed for safety reasons.

Gas log sets are relatively inexpensive and can have very attractive flames. They are highly inefficient and provide a minimum of room heating and a lot of warm room air vented up the chimney 24/7, with each cubic foot replaced by a cubic foot of cold air infiltrating the house.

2. A gas fireplace insert is a gas stove designed to be installed in an existing fireplace and uses the existing flue, which needs to have a chimney liner installed in it.

A direct vent gas fireplace insert is similar, except it vents out the back of the fireplace to a fitting behind the fireplace which takes in combustion air and exhausts combustion gasses, so that the existing chimney flue is not used.

Either type of gas fireplace insert burns gas fairly efficiently (65% or so), provides a reasonable amount of heat and radiant heat like a fireplace for a room, and can usually be operated with a remote control these days.

They usually have quite nice appearing flames these days.

Gas log sets are becoming increasingly obsolete, and gas fireplace inserts increasingly the more expensive but far more desirable choice.

 

[wooduser]

. Do I need to change the glass in my doors to ceramic?

No. The main purpose of glass doors with a gas log set is to marginally reduce the flow of warm room air out of the chimney 24/7.

With a gas fireplace insert, the glass doors would be removed as unnecessary, since the insert provides a view of the fire.

 

[ClintFlintFromBedrock]

With a gas fireplace insert, the glass doors would be removed as unnecessary, since the insert provides a view of the fire.

I'm keeping the current setup of a wood burning fireplace with doors and a fan system and just adding a gas line to it. This is in southern California (San Diego), so I'm not concerned about the amount of heat loss from the room when the fireplace glass doors are closed.

 

[wooduser]

So your plan is to install a set of gas logs.

Since your main desire is for a decorative flame effect, that should be fine.

And your glass doors will be useful in reducing the heat loss up the chimney, and perhaps the loss of cool air conditioned air during the cooling season.

You can have remote control of the burner flame installed with thye gas logs if you wish. This would save you from opening the glass doors and squatting down by the gas valve to turn it on and off.

You can ask about the added cost for that when you buy the logs and installation service. Should be around $100.

 

[Millbilly]

So your plan is to install a set of gas logs.

Since your main desire is for a decorative flame effect, that should be fine.

And your glass doors will be useful in reducing the heat loss up the chimney, and perhaps the loss of cool air conditioned air during the cooling season.

You can have remote control of the burner flame installed with thye gas logs if you wish. This would save you from opening the glass doors and squatting down by the gas valve to turn it on and off.

You can ask about the added cost for that when you buy the logs and installation service. Should be around $100.

All of the ones I sold requires the glass doors be open. I actually viewed the remote as a detriment because it increased the chance of damaging the equipment by running it with the doors closed.

 

[wooduser]

All of the ones I sold requires the glass doors be open.

I just looked at the specifications for several remote control systems, and none of them warned against using them with glass doors closed. But perhaps these specifications weren't complete ----they had no warnings about exposure to high heat at all.

But consider: the electric gas valve is in there near the gas logs in any case. I never encountered a gas valve that was obviously hot or being overheated. If the gas valve isn't being overheated, I suggest that the remote control receiver is going to be OK as well.


And in particular, the gas valve and receiver are usually well off to the side of the gas logs and the gas flame. They don't get a "look" at the flames to be hit by radiant heat from the flames, but instead are in the shadow of the logs.

I never found that the temperature when glass doors were closed was high. And the practice was that the glass doors be left open to provide enough combustion air to burn the flames properly. If the doors were closed, the gas flame would often start coming out towards the glass doors themselves, to get a supply of oxygen to burn the gas. So I found that people habitually operated the gas logs with the glass doors open if they had them in order to get an attractive flame pattern.

In short, I never found remote control receivers or electric gas valves I thought had been damaged by heat from gas logs used when glass doors were closed.

Of course, your experience and practice might be different. If you have a make and model with that kind of warning I'd be glad to be able to read up on what it says, if you'd care to post that information.

Always glad to improve on my judgement.


I think the biggest and hottest set of gas logs I encountered was at the main REI (Recreational Equipment Inc) store in Seattle. The logs were about six feet long and that thing had a LOT of gas going in it, and BIG flames! It was right near the entrance to the store, and had seating for customers who often sat around and enjoyed the fire. It was operated by a millivolt gas valve and a wall switch.

This big fireplace had a big set of custom glass doors which were kept closed to keep people out of the fireplace. There was enough combustion air coming in so that the flames were fine.

I don't recall finding that the gas valve was ever even warm ----cooled by the combustion air coming into the fireplace I expect, plus the gas valve was off to the side and not exposed to radiant heat from the flames.

I'll have to see if the store has a picture of that fireplace....

 

[wooduser]

https://www.google.com/maps/uv?hl=en&pb=!1s0x54901533ff76fe6b:0x59e3ef2b29f9c522!2m22!2m2!1i80!2i80!3m1!2i20!16m16!1b1!2m2!1m1!1e1!2m2!1m1!1e3!2m2!1m1!1e5!2m2!1m1!1e4!2m2!1m1!1e6!3m1!7e115!4shttps://lh5.googleusercontent.com/p/AF1QipPmyGDMVTx9hHJB9M_Wd6-KdXs5TToCRXqJeiHF=w213-h160-k-no!5srei main store - Google Search&imagekey=!1e10!2sAF1QipNswjTXnKmdGp9ld8TNTCbrdD0O-cREFdYhAx8N&sa=X&ved=2ahUKEwiJgeyAr8ngAhVSqp4KHd2MBcQQoiowE3oECAUQBg


Above is a link to the only picture I could find of "my" fireplace in the main REI store in Seattle. You can enlarge that somewhat to get a better view of this rather dramatic gas log fireplace. You can see that it's QUITE a fire, and they leave that running most of the time when the store is open, except during the summer.

 

[Millbilly]

I learn something new every day. But I thought that gas logsets, the type installed into wood burning fireplaces not bvent gas fireplaces, mostly if not all required the doors to be open. That store looks amazing I plan on stopping by when I'm in Seattle in a few months.

 

[wooduser]

My memory is somewhat vague, but I think the REI fireplace has pretty generous louvers allowing combustion air into the fireplace. So the flames burn fine even with the doors closed.

But the who idea of glass doors with most fireplaces with gas log sets is to reduce the airflow up the chimney, especially when the burner is off. The damper has to be wired open, so you have have a draft of heated room air going up the chimney 24/7 without doors blocking that air flow.

If the doors are that good at blocking air flow into the fireplace, they will probably not provide enough combustion air when the gas logs are on, which means the doors should indeed be open I would say. That's always been my recommendation, anyway.

But it's the weird flame appearance that really causes people to keep the doors open, I would suppose.

 

[ClintFlintFromBedrock]

Thanks for all the good information. The current fireplace has an outside air kit with two 4" diameter intake conduits, so I don't think combustion will be a problem.

 

[wooduser]

Thanks for all the good information. The current fireplace has an outside air kit with two 4" diameter intake conduits, so I don't think combustion will be a problem.

That's good, but you might find that the gas flame still looks for fresh air to burn. That might cause the flame to be diverted towards those fresh air inlets, or other wise look weird.

If that happens, opening the glass doors while the fireplace is burning would be the way to solve that issue.

When the burner is shut off, you can close the glass doors to reduce heated room air from being drawn up the flue.