Joined on March 23, 2012
Last Post on February 26, 2013
@ February 26, 2013 4:51 PM in Check Valve WoesThanks for your prompt help.
My less-than-ideal plan for using a common return line for two zones makes it necessary to install these check valves away from the boiler room, and I decided to go ahead and remove the springs. It actually didn't take that long and water flow seems even and quiet now. So far, this looks like success.
@ February 26, 2013 2:06 PM in Check Valve WoesHello Everyone!
I need the benefit of experience. Here's the problem:
1. Installed iron rads in two different zones with common return line. Found that return flow from one zone was back-flowing through rads in neighbouring zone, delivering heat there even when thermostat called for none.
2. Installed swing check valve in floor frame where rad pipes travel, found the check valves sometimes made noise. Also reconsidered the wisdom of installing check valve in floor frame that would be sealed under new hardwood floor later on.
3. Removed swing check valves and installed spring check valve in pipe leading down from rad into the floor. Idea being ease of future replacement and quiet operation.
4. Check valves only installed in two of the four rads in the affected system, now all water flows to the two rads with no spring check valves, unless those rads are shut off manually. And even when these valves are shut, flow through rads with spring checks doesn't always happen. It seems the springs are too strong. There's definitely no air in the lines to block flow.
Is there any value in me pulling the rads off again, removing the springs from the check valves, then buttoning everything up again? The spring checks are in a vertical position, so gravity and any attempt at back flow should close the valves when they need to be closed.
Am I on the right track? Will the check valves make rattling noises without their springs?
In hindsight, I should never have installed a common return line for two zones, but I can't change that now.
Thanks a million!
@ April 9, 2012 12:08 PM in Rads and TRVsHello Everyone!
I'm planning an installation where iron rads will be installed in various places around a home, and I'll be controlling them with TRVs. I understand how these valves start and stop water flow depending on room temperature, but I'm thinking that I should probably be plumbing in some kind of balancing valve for each rad, too. An unavoidable part of this installation connects very different lengths of pipe to each rad. I'm afraid that if/when all the rads call for heat, it'll all flow through the rads with the least pipe leading to them. Should I not flow balance the system with the TRVs all wide open, then let room conditions and the TRVs control the flow? And if I should be installing balancing valves, what kind? Are ball or gate valves going to wear or erode in strange ways over time if water is flowing through them when they're partially closed? Is there some kind of visual flow meter that I could possibly plumb into the various branches to help me balance them? Sort of like the flow meters in an infloor hydronic system?
Also, what's the best brand of outdoor air temperature sensor to use to control the circulator pump for a TRV rad installation? What's the best brand of flow control valve that bypasses the rad lines when all the TRVs are closed?
Thanks very much for your help!
@ March 26, 2012 9:57 AM in Did I Make a Mistake?Good Morning Bob,
Thanks a lot for pointing me in the right direction. Those Webstone valves look terrific. I've got an order ready to go.
@ March 25, 2012 5:32 PM in Did I Make a Mistake?Hello Bob,
Thanks very much for your generous explanation of a DHW system that works. I'm going to tear out what I have, then build what you recommend. Before I do, I'd like to explain a little more about what I did, then ask a couple of questions (just to make sure there's no more tearing out to be done).
I didn't explain in my original post that I'm not using a flat plate heat exchanger, but rather a sidearm. My thinking was that a sidearm would be more resistant to scaling up. Rather than letting it work by thermosiphon, I put the 15-58 on top to speed water flow and boost hot water production. (My wife and I have 5 kids, so we go through a fair amount of hot water).
The long and the short of it is that the sidearm isn't producing significant hot water. I've fooled with flow direction (first counterflow, then unidirection), with differences in flow rates (I rigged it so I can vary DHW flow rate with a valve, beyond the variation possible on the pump itself), and a few other things. I've monitored water temperature in and out of the sidearm using a thermocouple on my Milwaukee infrared thermometer, and in the tank itself. I can leave the sidearm working all night long, yet only see a 5º or 10º rise in temperature in the 60 gallons. At both slow and fast flow rates, the sidearm only causes a 3º or 4º temperature rise. I'm at a loss as to why the sidearm doesn't work for me, since sidearms do seem to work for other people. The only thing I can think of is that my basement is unheated (about 50ºF) right now. My plan was to insulate the lines and sidearm, but I'm not confident enough that this would make a difference, so I won't bother. The sidearm is a stainless steel double-walled unit. Perhaps a single wall sidearm would work better. Do you have any experience with these?
So, as I said, I'll be tearing the whole sidearm/circ pump out and replacing it with a flat plate exchanger in series with the cold water intake into the DHW tank. You mentioned a 5x12 20 plate. Will my brand new 3x8 40 plate Bell & Gossett work? (I imagine so, but want to be sure I'm not missing things. It's rated at 225K btus/hr).
My plan is to plumb the flat plate in with unions right at the exchanger outlets, allowing me to take it off conveniently for treatment with vinegar as needed.
Are my ideas sound?
Thanks a million, Bob!
@ March 24, 2012 9:05 AM in Did I Make a Mistake?Thanks Bob. I'd heard of plumbing the flat plate into the incoming cold line, but it seemed to me that it wouldn't keep the tank hot unless lots of hot water was used. But your experience convinces me not to worry. I'll go with your option.
Bye, and thanks.
@ March 23, 2012 10:05 AM in Have I Seriously Sinned?Good Morning Everyone,
I've got an outdoor wood boiler (open system) with PEX pipe bringing 20% glycol into a house. Boiler water is also treated with anti-corrosion chemical. Inside the house there's a small section that's plumbed with a total of 18" of galvanized pipe -- some elbows, a few tees and a couple of unions, all together in two neighbouring sections. I've read that nasty, gooey things happen when galvanized and glycol get together, but is this really an issue with such a small bit of galvanized? Online I read phrases like "could be a problem", "may cause problems", and "should be avoided". I'll tear the galvanized all out and replace it with black iron if it's prudent, but is it really? What would you do?
Thanks so much,
@ March 23, 2012 9:56 AM in Did I Make a Mistake?Hello Everyone,
I've just installed an outdoor wood boiler, and I'm using part of the heat to take over from electricity on a 60 gallon DHW tank in a basement. I've plumbed a Grundfos 15-58 into a very short loop of galvanized pipe outside the heater to run tank water through a heat exchanger. The 15-58 is an iron circulator, and I now realize I should have gone bronze. Is it worth buying a new pump and changing it? After all, the DHW tank is steel (with a fresh anode installed). Also, jet pumps and piston pumps for well systems are iron or steel, and they seem okay.
I like to do things right, but how wrong is my current set-up?
Thanks a million everyone!