| Author | Message | ||
| Mike Stegeman (Mike_s)
Registered Member Username: Mike_s Post Number: 1 Registered: 3-2007 Posted From: 75.4.39.230 Rating: N/A |
Hi I am installing a hydronic heating system in by bus. I am installing 4 toe-space heaters and will run individual PEX lines to each heater. What I would like to know is, should I use 1/2 ” or 3/4" lines, and should they have the O2 barrier or is regular PEX Thanks Mike | ||
| David Evans (Dmd)
Registered Member Username: Dmd Post Number: 157 Registered: 10-2004 Posted From: 71.125.61.116 Rating: N/A |
Mike, use the barrier only for heat. The 3/4 would be better but its hard to bend. You can use the large sweep elbows or 2 45's to reduce the flow resistance. | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 534 Registered: 12-2000 Posted From: 76.1.180.218 Rating: N/A |
Mike, where did you find the toe kick units? Jack | ||
| joe padberg (Joemc7ab)
Registered Member Username: Joemc7ab Post Number: 93 Registered: 6-2004 Posted From: 66.38.159.33 Rating: N/A |
Mike My suggestion to you would be be to go with the largest size available 1" is available as far as I know, which would lower your flow resistance, thus lowering the demand on your circulating pump. The difference in headloss per 100 ft of lenght at 140 F and 2 GMP of flow is 16 times lower in 1" PEX as compared to same condition in 1/2" PEX. Also make sure that everything is run in parallel, not series. Go for Bpex if there is anything in the system that could rust. This link has lots of good info charts tables etc. www.radiantsite.com Joe. | ||
| Jerry Campbell (Jerrync)
Registered Member Username: Jerrync Post Number: 70 Registered: 7-2006 Posted From: 69.132.150.103 Rating: N/A |
Jack I got mine at Campbell and Brown in Charlotte NC at about 95.00 each (Message edited by Jerry@nc on March 25, 2007) | ||
| Mike Stegeman (Mike_s)
Registered Member Username: Mike_s Post Number: 2 Registered: 3-2007 Posted From: 75.4.39.230 Rating: N/A |
Jack , I got mine directly from Aqua-Hot through there parts department. Cost was $ 120.00 each. You can see them on there web page ...http://www.hydro-hot.com/rv-lifestyles-accessories.htm | ||
| Ron Walker (Prevost82)
Registered Member Username: Prevost82 Post Number: 272 Registered: 11-2003 Posted From: 69.19.14.16 Rating: N/A |
Hi Jack ...I installed a hydro-hot in my bus. I bought a kit from Vehicle Systems. They sent me high temp PEX that was 5/8 ID, rated for 200+ degs. We have 3 Cozy 3 heaters (toe-kicks) in the salon and 1 each in the bathrm & bedrm. Ran the PEX down the curb side walls of the bus ...I strap the wall with 1x2 and added rigid insulation and the Pex (hot and return) run down the wall in this cavity Ron | ||
| Nick Badame Refrigeration Co. (Dnick85)
Registered Member Username: Dnick85 Post Number: 91 Registered: 2-2006 Posted From: 68.45.178.44 Rating: N/A |
Hi Mike, There is also Aluminum PEX [AL-PEX] that holds it's shape when you bend it. For close quarters like a bus it may be a better choice. As far as the pex size, the opening of your toe kicks will determine the resistance. If you are home running your supply and return, then stick with the diameter of the toe-kicks inlet and outlets sizes. Going larger on the tubing will not help flo if your restricted to 1/2" on the kicks. Good Luck Nick- | ||
| Mike Stegeman (Mike_s)
Registered Member Username: Mike_s Post Number: 3 Registered: 3-2007 Posted From: 75.4.39.230 Rating: N/A |
THANKS ALL !!! Mike | ||
| Mike (Mikemc9)
Registered Member Username: Mikemc9 Post Number: 18 Registered: 5-2004 Posted From: 4.242.183.234 Rating: N/A |
I too am looking for a hydronic heating system for my MC9. Any other types or home made rigs besides the Hydro(Aqua)-Hot systems. Like most others, looking to save a buck, that $6,000+ sure hurts. Thanks, Mike | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 537 Registered: 12-2000 Posted From: 76.1.180.218 Rating: N/A |
Taking the advice of Ray Edwards, another busnut, I contacted Nick at Nimco in NJ and purchased a used ProHeat 45,000 BTU unit. I have not got mine installed yet. After purchasing the proheat, Ray went to a Salvage yard and bought a couple heater cores, made boxes for them and added a couple "muffin" fans. Total cost of the system: approx. $600. His system is bus heat and engine preheat only, it does not tie into his hot water heater. Jack | ||
| Brian Elfert (Belfert)
Registered Member Username: Belfert Post Number: 33 Registered: 7-2006 Posted From: 132.148.80.215 Rating: N/A |
Be aware that the Proheat units from Nimco are pulls from trucks and buses and may not be pretty. Nimco chops all the wiring harnesses and fuel line right at the unit so the wiring will require splicing. The price is good so the issues aren't unexpected. I haven't used mine yet, but I assume it works. The heater cores with fans that I bought only have 1/2" PEX connections so no real reason to go bigger than that for me. Brian Elfert | ||
| RTAntonio (Gr8njt)
Registered Member Username: Gr8njt Post Number: 1 Registered: 3-2007 Posted From: 68.39.161.3 Rating: N/A |
How much is NIMCO asking for the Proheat units pulled from other trucks and buses? Thanks | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 540 Registered: 12-2000 Posted From: 76.1.180.218 Rating: N/A |
I don't give prices I paid because with supply and demand, prices change. Call 1-800-526-8055 and ask for Nick. Jack | ||
| Kyle Brandt (Kyle4501)
Registered Member Username: Kyle4501 Post Number: 307 Registered: 9-2004 Posted From: 65.23.106.193 Rating: N/A |
Your tubing size requirements will depend on the flow requirements, length of run, desired pressure drop. The pressure losses in the system are cumulative. The pressure drop in 100 feet of pipe for 1gpm flow (water at 60F) For 3/8" pipe (0.493" id) = 1.85 psi for 1/2" pipe (0.622" id) = 0.60 psi The pressure drop in 100 feet of pipe for 5gpm flow (water at 60F) For 3/8" pipe (0.493" id) = 36.7 psi for 1/2" pipe (0.622" id) = 11.2 psi (from CRANE technical paper No. 410) So you may need larger tubing for satisfactory performance, it depends on how YOUR system is designed. The larger tubing holds a larger volume of water, so that will require a larger expansion tank. Raising the operating temp reduces flow required (which reduces line size & tank requirements) but may put more stress on the seals & tubing. Etc. . . . . Ain't nothing as simple as it looks. One of these days, I'll get brave & tackle this on my bus. | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 111 Registered: 7-2006 Posted From: 4.240.144.79 Rating: N/A |
FWIW...just a bit of interesting information...today I purchased three bronze fittings; a 2 inch nipple (1/2), a 3/4 to 1/2 bushing and a 3/4 Street EL. Plumbing supply house, not a hardware store. Nearly $16...(wow, I said). The counter person said that is nothing compared to copper. She went on to inform me a 1/2 x 20 foot stick of copper.........are you ready for this??? $70.00 (seventy!!!) My coach is plumbed with 1/2 and 3/4 inch copper thruout. Brass or bronze fittings. Done mostly 5 years ago. I chose that instead of Pex because of $$$ invested. (so far, not a single leak) Sounds like a bad choice today if one is on a budget. They confirmed and said that most plumbing applications today are going that way....to Pex. Times....they are a'changin'!  RCB |