New Garn Install

[GarnNewbie]

Hello all, I live in Huttonsville, WV and I purchased a Garn 2000 and am currently looking for the heat transfer products like piping, pumps, heat exchanger, etc. I am definitely not a heating expert, and would really appreciate some your guys' input on my Garn install. My Garn will be located in a lean-to area about 130 ft from my house. I have a 3 story brick house, approx 5400 sq ft, with the old cast iron radiators. Based off of an EDR ratings chart I found online, my radiators have a heating capacity of 183,000 btu/hr. When we originally bought the Garn, the dealer quoted us for some Microflex 50mm DUO at $33.81/ft, a Taco 013 BF4-J Cast Iron w/Bronze Cartridge at $226.20, a Taco 007 BF5-J, Cast Iron w/Bronze Cartridge at $90.52, a LB31-70 (L-line Plate-to-Plate 1" NPT) 70 plate Heat exchanger for $495.00. I'm not even sure what size pipes, pumps, and heat exchangers I should be looking for, but those are the ones he quoted us for. I looked at the microflex website and they were charging $67.81/ft, so I don't know what the deal is with that, but if any of you guys know of a good deal on some piping, pumps, heat exchangers, mixing valves, I'd appreciate the input, and any other suggestions you might have. Thanks in advance for any help you can offer

Sean W

 

[stee6043]

I plumbed my system with 1-1/4" black pipe. 90% of it came from The Home Depot and the remaining 10% came from grainger.com. Mostly the oddball size nipplies and weird fittings all came from grainger.com. I'd think you'd be closer to the 1-1/2" to 2" range for your system. You're going to be moving a few more BTU's than I do.

Google "patriot supply" for a good online source for most of the other stuff. Pexsupply.com is also popular but their customer service can be HORRIBLE.

I've heard some folks online have had good luck buying heat exchangers on Ebay. I bought my through Cozy Heat (sponsor here)....

 

[Jim K in PA]

Sean - welcome to the Boiler Room.

The first thing you need to do is calculate your heat LOAD. The output capacity of your current heating system will be important a little later, but you need to size your transfer equipment to handle the appropriate load. What calculations did you do with Dectra or TWH to decide on a 2000 vs a 1500?

 

[GarnNewbie]

Jim,

TWH did some calculations for me, but I can't remember exactly what they were, and TWH didn't give me a copy of the info. It sounds like I may have to contact them. Question- If my radiators' estimated capacity is 183,000 btu/hr, then why not size everything to say 200k btu/hr(a little over to compensate for estimate inaccuracy)? If my heat load is less than capacity, then I'm good. If my heat load is more than my capacity, well then I'd have to come up with alternate solutions there, but the sizing of the piping/pumps/heat exchanger wouldn't help in that case right? Either way, it seems like the sizing of the the heat transfer elements should match with the capacity, since that's really all I can handle. Anyway, I know I'm probably way off here, but that's just what makes intuitive sense to my heating-challenged mind. Well, I'm just a bit uneducated at this point, but hope to make progress in that respect.

I've been looking at the 1 1/2 " pex with spray foam. And that's about as far as I've gotten with the heat transfer stuff. Due to unforeseen circumstances this summer, I haven't been able to tackle this project the way I had planned so I'll be scrambling a bit to get it installed in time for the cold weather. I did get my trench dug this last weekend, but I'm thinking that was a bad move considering I can't go to my local supply store and find some 1 1/2" pex. Sigh