Is it worth installing modine heater PA105AB
- Thread starter Duramax junkie
- Start date
OP
Duramax junkie
Member
Thanks for any input
Scott V
Well-known member
I guess I'd be concerned with getting parts. A quick search showed discontinued on this site...
http://www.littlegreenhouse.com/accessory/heater2.shtml
http://www.littlegreenhouse.com/accessory/heater2.shtml
warren57
Well-known member
Of course it's worth installing! You just saved $300-500 bucks.
Good find. Parts are no problem. May not be as high efficiency as a new unit, but the price is right.
Mo dine is a good brand and our shop works on everything, moline and Rheem have a lot of 20+ year old units running fine.
Good find. Parts are no problem. May not be as high efficiency as a new unit, but the price is right.
Mo dine is a good brand and our shop works on everything, moline and Rheem have a lot of 20+ year old units running fine.
OP
Duramax junkie
Member
Thanks have found most parts still available except for the burner manifold and since the price is only $150 for this unit if it works can afford to fix if the main valve is no good or other electrical items.
I do have a venting question on this heater can I vent it horizontally out a side wall or should it be vertical being it doesn't have a vent fan?
I do have a venting question on this heater can I vent it horizontally out a side wall or should it be vertical being it doesn't have a vent fan?
warren57
Well-known member
Not really, the unit is UL Listed, as an assembly. That assembly was listed with a verticle vent. Now, will it work vented horizontally... Yes, with a horizontal vent cap.
Now you can go horizontally thru the wall (pitched slightly up hill) then turn up vertically to a point above the roof. As for height above the roof, there should be no obstruction horizontally (the roof) within 10'. Many think you have to be higher that the peak, no so.
Why would it need a burner manifold? That is basically a piece of schedule 40 pipe drilled and tapped to screw in the burner orfices. Not a part that would ever where out????
As for operation controls, a operating klixon controller to set discharge air temp, wired in series with a high limit klixon controller set to shut the gas off at a too high condition. Many of the old units had the fan start on a call for heat and shut down when temp. Was satisfied. Newer units start the fan when the exchanger reaches a set temp and continue after burner shutdown until the exchanger reaches a cool down temp. (Another spdt klixon with an adjustable dead band.
All pretty easy stuff and klixon switches cost about $10-15.
And gas valve...$100-125.
So be careful if it needs to many parts, as you could quickly get to the price of a new unit!
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OP
Duramax junkie
Member
Don't think it really needs anything just a cleaning I just found that was the only part not available anymore that's all thanks for the helpful info warren
warren57
Well-known member
Glad to help, you can PM me if you have any issues and want to talk over the phone.....
lynnbilodeau
Well-known member
I have a similar heater (Modine PA150A) already mounted in a large garage. There is no venting. I realize if I run it very much, I am probably dumping carbon monoxide into the air, so I would like to vent it.
Can I run approximately 12 foot horizontal with a slight pitch up, then go up the wall and out the roof? Do I need some kind of power vent, or will simply running vent pipe work OK?
Thanks for any help.
Can I run approximately 12 foot horizontal with a slight pitch up, then go up the wall and out the roof? Do I need some kind of power vent, or will simply running vent pipe work OK?
Thanks for any help.
sms1974
Well-known member
Sounds like you've got it figured out for the most part...
I will just throw this out there, remember the air that goes up and out the vent (exhaust) has to be replaced with air coming back in to the space. granted a lot of garages / shops are not all that tight but I have seen several problems arise when you don't have a combustion air make up....
I will just throw this out there, remember the air that goes up and out the vent (exhaust) has to be replaced with air coming back in to the space. granted a lot of garages / shops are not all that tight but I have seen several problems arise when you don't have a combustion air make up....
Mr_P
Well-known member
Hey Duramax Junkie. 11+ year follow up here... How did the install go if you did go thru with it? And also, if installed, how has it held up over the years?
He hasn't been here since 2015, so don't expect an answer!
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Mr_P
Well-known member
Touché. I wonder now if he ended up going with a newer unit after all. I seen one pop up for sale near me for $60, but not sure if I want to deal with it.
it's a gamble . unless you can check it out & see it operating , I would probably pass .
If it's in ok shape, the next biggest thing is the size. These old heaters are often pretty big. If you have a small insulated garage, you aren't going to be happy.
Natural draft requires a vertical chimney. When I did mine I didn't want a hole in the roof. I went through the sidewall then used a tee to go vertical outside the building. Having the majority of the chimney outside is not ideal by any means but it's worked ok for my use.
I saved an 70% 125,000 btu furnace that I used in my 28x38x9 lined but uninsulated garage. I did convert it to electronic ignition with used part's. Works pretty well but last fall I did save a 75,000 80% furnace that I might swap in if I get the urge.
fitter30
Well-known member
Horizontal vent can be done but needs a flue bootster fan and a safety control is fan doesn't run. Cost more that the heater. CJ3 model
We had a guy put one on the boiler where I go to church. I never have really liked the thing, should have just lined the chimney. Some of it's install issues but gravity is simple and works.
fitter30
Well-known member
Guess i installed 10 in span about 25 years on natural gas boilers. From 500k to 2 million btu boilers. With a airflow switch and thermal switch mounted inside the draft hood. Had one fan fail motor locked up pressure switch shut the boiler down. They were all Tjernlund brand. Thought they were well made.
When I was selling HVAC parts and equipment I had a contractor ask me to stop and look at a situation at an old church that was still active. The chimney liner was collapsing so the oil furnace wouldn't run. I told him to tear out the oil furnace, (It was old and in need of replacing any way) and drop in a propane 95% furnace and vent it out the wall. He called me back a few weeks later and we went back to the same church and he installed a new oil furnace and a Tjernlund side wall vent kit. Funny thing was the Tjernlund was darned near as much as the propane furnace, so it would have be a lot less money to install a 90% propane furnace. I just stood there in shock looking at what he had done. The propane furnace would need very little service where an oil burner should be looked at every year of two. Plus simpler than adding a Tjernlund sidewall vent.
I'm not saying they are bad. I'm just not in love. Ours is pulling exhaust from a 900k gas boiler from the '70s. The chimney supposedly had a cracked clay liner so they used the tjerlund to vent through the wall.
My real complaints are install problems. The exhaust hood is too close to the air intake. We get a lot of condensation in the brick and mortar around the hood so it's not sealed well. It's definitely eating at the mortar.
I would think we could have had a stainless liner made for the chimney. It was built for an oil boiler in the '50s so I would guess there is enough room. I think I will push for that someday.
I guess I'm in charge of it now. Couldn't get anybody to diagnose the intermittent lockout problems we were having. I put a new Honeywell flame control in it and redid some things in the control cabinet.
My real complaints are install problems. The exhaust hood is too close to the air intake. We get a lot of condensation in the brick and mortar around the hood so it's not sealed well. It's definitely eating at the mortar.
I would think we could have had a stainless liner made for the chimney. It was built for an oil boiler in the '50s so I would guess there is enough room. I think I will push for that someday.
I guess I'm in charge of it now. Couldn't get anybody to diagnose the intermittent lockout problems we were having. I put a new Honeywell flame control in it and redid some things in the control cabinet.
OP
Duramax junkie
Member
Just happened to find this today when I googled the model number of my heater. (Forgot I even posted about it) To answer your question install went well hung it myself, a trip to Menards ran vent pipe out the roof and had the local HVAC business plumb the natural gas to it. Been going strong since haven’t had any issues with it besides at times if garage temperature is below 10F the gas valve is slow to turn on if it hasn’t ran in a couple of days
Mr_P
Well-known member
Thank you everybody for your advice on here. Especially the original poster. I ended up with this freebie Sterling model QVF-75 built in 1996 from an estate sale where the house was going to be torn down for new housing. Now I just need to verify where I want to mount it. If I mount it right in the middle of the rear of the garage, I don't have to move too much to prep for the guy running my gas line from the basement to the garage. Most of the time I see these sitting on the corner of the garage, but unfortunately the first choice of the back left area is not accessible because of a finished room above that side of the garage.
