HoosierBuddy
Well-known member
Hey guys,
I've never seen a writeup on one of these bad boys, so I thought since I had a little experience with one, I'd pass it along.
Recently, at work, we had one of our old 70's vintage hanging heaters quit. In checking it out, the tech noted the heat exchanger was severely cracked and it was decided that any repairs would simply be throwing money away. When searching for a higher efficiency replacement for the old 80% heater, I became intriqued with the Modine Effinity line due to the high efficiency rating.
Well, a quick call to my normal source for all things HVAC came back with a quote of roughly $4000 for a 155,000 BTU heater and concentric vent kit. That almost made me rethink the whole idea! Fortunately, I got a second quote from a wholesaler in another area and they quoted the same heater for $2300. Still a lot...but DAMN dude...over $1700 wholesaler difference on one heater?
Well, the heater came in a week or so after I ordered it and we got it installed out in the shop earlier this week. When mounting it in place of the old 180,000 BTU unit we were able to use the existing hole through the roof to install the concentric vent kit vertically, so that worked out pretty well. Our other choice would have been to run PVC horizontally for about 40-feet to get to an exterior wall and bore a hole through the concrete blocks...so we chose the easier method of just going up. The Modine concentric vent kit mounts to the ceiling and you use 4" (or smaller depending on the BTU of the unit) PVC to hookup between the heater and the box. Slick.
Mounting the unit was accomplished with 4 allthread rods and some angle steel. Pretty standard stuff.
We also had to make allowances for the condensate drain. Now, in this instance we actually had a nearby condensate drain to plumb to, so no big deal, but it's something to bear in mind. We used the old honeywell heat-only t-stat from the old unit as it still works great and is pretty much bulletproof.
The unit started up with no problem at all. The thing we noted immediatly though is the fan is a lot louder than the one in the 37 year old unit it replaced. I've noted this with other high efficiency equipment I've installed. They blow a lot more air than the old stuff.
Anyway, it's been in operation for a few days now with no issues. Even though the rated efficiency of the new unit is only 13% higher than the old one, I would guess it's actually 1/3 more efficient due to the age and condition of the unit it replaced. Also, all of us are about 1/3 smarter now that we aren't inhaling CO all day from a cracked heat exchanger.
Which brings me to the second thing. After finding the heat echanger in this unit cracked, I had our tech check a similar (slightly smaller) unit in the adjacent warehouse bay. It was cracked too. 38 years is evidently too long to use a hanging heater. Luckily the unseasonably warm weather allowed us to get by without it (it was registering 7 parts per million CO, well within OSHA limits...but still not a great idea to run) and I've ordered a second Effinity 93 to go there. This one is 110,000 BTU and I'm certain it will be a little quieter. I also had to get the $80 optional condensate pump, as we'll have to plumb that line up, over, and down to get it to drain.
If I were to build our shop today, I'd go hydronic in-floor using a high efficiency gas boiler for heat, because after the experience I've had in my home garage where I LOVE IT...but where you already have a floor it's tough to beat gas fired unit heaters for low cost operation, extremely quick recovery, super easy installation, and rock solid dependability. Once you decide to go that route it may be tough to come up with the extra cash for a fully condensing heater...but I'd recommend considering it due to the lower operating cost. If the unit lasts 20 to 25 years, that difference in cost will certainly be justified...PARTICULARLY if you are heating a high-bay concrete block warehouse with a lot of overhead doors and poor insulation like we are.
Phil
I've never seen a writeup on one of these bad boys, so I thought since I had a little experience with one, I'd pass it along.
Recently, at work, we had one of our old 70's vintage hanging heaters quit. In checking it out, the tech noted the heat exchanger was severely cracked and it was decided that any repairs would simply be throwing money away. When searching for a higher efficiency replacement for the old 80% heater, I became intriqued with the Modine Effinity line due to the high efficiency rating.
Well, a quick call to my normal source for all things HVAC came back with a quote of roughly $4000 for a 155,000 BTU heater and concentric vent kit. That almost made me rethink the whole idea! Fortunately, I got a second quote from a wholesaler in another area and they quoted the same heater for $2300. Still a lot...but DAMN dude...over $1700 wholesaler difference on one heater?
Well, the heater came in a week or so after I ordered it and we got it installed out in the shop earlier this week. When mounting it in place of the old 180,000 BTU unit we were able to use the existing hole through the roof to install the concentric vent kit vertically, so that worked out pretty well. Our other choice would have been to run PVC horizontally for about 40-feet to get to an exterior wall and bore a hole through the concrete blocks...so we chose the easier method of just going up. The Modine concentric vent kit mounts to the ceiling and you use 4" (or smaller depending on the BTU of the unit) PVC to hookup between the heater and the box. Slick.
Mounting the unit was accomplished with 4 allthread rods and some angle steel. Pretty standard stuff.
We also had to make allowances for the condensate drain. Now, in this instance we actually had a nearby condensate drain to plumb to, so no big deal, but it's something to bear in mind. We used the old honeywell heat-only t-stat from the old unit as it still works great and is pretty much bulletproof.
The unit started up with no problem at all. The thing we noted immediatly though is the fan is a lot louder than the one in the 37 year old unit it replaced. I've noted this with other high efficiency equipment I've installed. They blow a lot more air than the old stuff.
Anyway, it's been in operation for a few days now with no issues. Even though the rated efficiency of the new unit is only 13% higher than the old one, I would guess it's actually 1/3 more efficient due to the age and condition of the unit it replaced. Also, all of us are about 1/3 smarter now that we aren't inhaling CO all day from a cracked heat exchanger.
Which brings me to the second thing. After finding the heat echanger in this unit cracked, I had our tech check a similar (slightly smaller) unit in the adjacent warehouse bay. It was cracked too. 38 years is evidently too long to use a hanging heater. Luckily the unseasonably warm weather allowed us to get by without it (it was registering 7 parts per million CO, well within OSHA limits...but still not a great idea to run) and I've ordered a second Effinity 93 to go there. This one is 110,000 BTU and I'm certain it will be a little quieter. I also had to get the $80 optional condensate pump, as we'll have to plumb that line up, over, and down to get it to drain.
If I were to build our shop today, I'd go hydronic in-floor using a high efficiency gas boiler for heat, because after the experience I've had in my home garage where I LOVE IT...but where you already have a floor it's tough to beat gas fired unit heaters for low cost operation, extremely quick recovery, super easy installation, and rock solid dependability. Once you decide to go that route it may be tough to come up with the extra cash for a fully condensing heater...but I'd recommend considering it due to the lower operating cost. If the unit lasts 20 to 25 years, that difference in cost will certainly be justified...PARTICULARLY if you are heating a high-bay concrete block warehouse with a lot of overhead doors and poor insulation like we are.
Phil
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