Help me. Modine garage heater
- Thread starter Cwill375
- Start date
is it a new heater? what does the spec label say , propane or nat gas?
does it have a sticker that says it's converted?
why do you think it's too big for nat gas?
what size/model heater ?
does it have a sticker that says it's converted?
why do you think it's too big for nat gas?
what size/model heater ?
Sorry there is no labels on it there is one that says it’s propane but I can put a pencil lead in the hole of the orifice I just got a new gas valve for it due to the old one being bad. When I go to turn it on you can hear the gas flow and then get the explosion ignition where it like getting to much gas
I think this is beyond average DIY, the gas valve probably needs to be adjusted for proper pressure . the orifice will need to be sized properly, and if there's no labels on it, your insurance company may have issues with it.
there are conversion tables on-line to help with orifice sizing, but you should talk to a pro, in my opinion
there are conversion tables on-line to help with orifice sizing, but you should talk to a pro, in my opinion
finn
Well-known member
Don’t know about Modine, but other manufacturers offer conversion kits with new orifices, pressure regulator springs, and installation / setting instructions for conversions.
Conversion isn’t exactly plug and play.
Buy the kit, or a new heater. They’re incredibly inexpensive.
Conversion isn’t exactly plug and play.
Buy the kit, or a new heater. They’re incredibly inexpensive.
Pruittx2
Well-known member
Mr Heater 80Kbtu Nat gas on left Propane on Right.
Taken during new install conversion
Propane typically runs at 11" W.C. pressure while NG typically runs at 3.5" W.C. pressure, so pressure needs to be set for which ever fuel.
There should be some stamped markings on the orifice. I have a 75K Modine and it runs a single #21 orifice (.159" dia) that feeds into a mixing tube and five burners work of that.
There should be some stamped markings on the orifice. I have a 75K Modine and it runs a single #21 orifice (.159" dia) that feeds into a mixing tube and five burners work of that.
I had convert my mode from propane to natural gas, so I have went through this exercise. My was a 75K BTU unit and had the labeling on the side, so it was pretty straight forward.
A 45 orifice is a .082 dia hole. For LP at 11" W.C. pressure, that works out to 46969 BTU output.
If the new valve was setup as NG specific, then the pressure range is set much lower than propane but it is not set to a specific number as different appliances run at different pressures.
1) You need to get a manometer and adjust it to 3.5" W.C. (That's what my unit labeling said for example). You can make your own manometer, goggle it but your on your own. I had a local connection, so he dialed it in for me.
2) Obtain the orifice size that has the same BTU output as the LP fuel at 11" W.C. In this case, if you run NG at 3.5" W.C. pressure, you need a number 29 size orifice and that gives 46961 BTU output.
A 45 orifice is a .082 dia hole. For LP at 11" W.C. pressure, that works out to 46969 BTU output.
If the new valve was setup as NG specific, then the pressure range is set much lower than propane but it is not set to a specific number as different appliances run at different pressures.
1) You need to get a manometer and adjust it to 3.5" W.C. (That's what my unit labeling said for example). You can make your own manometer, goggle it but your on your own. I had a local connection, so he dialed it in for me.
2) Obtain the orifice size that has the same BTU output as the LP fuel at 11" W.C. In this case, if you run NG at 3.5" W.C. pressure, you need a number 29 size orifice and that gives 46961 BTU output.
Dude that was the best info I have gotten from anyone thank you very much this will be a big help again thank you
number drills are the sizes for orifices in most cases.
if you have/ get a number drill set you can use them to measure the orifice size. ie a number 45 drill is .082
https://littlemachineshop.com/reference/numberdrillsize.php
if you have/ get a number drill set you can use them to measure the orifice size. ie a number 45 drill is .082
https://littlemachineshop.com/reference/numberdrillsize.php