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Re: Question about Erie zone valve
The most common 3/4 sweat Erie is the 7.5 Cv. It has a 17 psi shutoff. You do not have a pump in your system capable of 17 psid. If you did all the valves would be blowing by, all the time.
The static pressure in your system, no pumps running would have the same pressure on both sides of the paddle. The spring tension has the ability to hold 17 psi regardless.
hot_rod
Re: Question about Erie zone valve
First simple test is set it upright on a bench and pour water into it. Does it holdi
The best way is to power the valve open, start flowing water, then remove power, in this example it closed against 20 psi and held bubblefree.
This tests it at actual working condition, with the exception of 180° water
hot_rod
Re: Replacing gas Navien boiler with electric boiler for hydronic heat?
I would not REPLACE the propane boiler. If you want to use electric, ADD an electric unit then you have more options.
JMWHVAC
Re: Augusta Stone Church
@leonz
Im glad that burning coal works for you, but am I to understand that you’re suggesting that as a mechanical contractor I should attempt to sell this as a viable solution to the church? Do you really think that they would want to have to have a coal bin installed, find a coal supplier, have someone be there at least twice a day to shovel coal, and put up with the mess that it would create?
Ironman
Re: Replacing gas Navien boiler with electric boiler for hydronic heat?
I would add the electric and switch between the two when the costs are best. I would not go ripping out a perfectly fine working propane boiler and switching to all electric.
Re: Augusta Stone Church
With the boiler being that much oversized you probably smart to change it out.
If the run is not too long maybe a HW zone off the steamer would work for the offices. But if not much load electric you can't beat the simplicity and lack of needed maintenance.
Re: Low return water temp protection methods
if you are doing it with an injection pump and an on/off control you need to be able to make that circulator's flow low enough that it doesn't immediately cool the boiler to the point the aquastat turns it off again as soon as it starts which probably is a combination of pump size and a throttling valve.
It would seem if you are going low flow high delta that you need to be able to throttle the flow through the close radiators most of the way off with the radiator valve to make the water find its way to the far end of the system. if you're dealing with 2" or 3" pipes and 3/4" or 1" radiator runnouts all the heat is going to want to get off at the first couple radiators without a way to throttle the flow.
mattmia2
Re: How can I use 90 F degree water to heat my new house?
Put a boiler in with baseboard heat as a booster a stand alone system.
use the 90 degree water through a heat exchanger to run radiant heat and preheat your domestic hot water.
You can go oversize on the radiant tubing to maximize use of the 90 degree water which will probably do the job for a good portion of the winter.
What the radiant can't do the boiler will
.Nice and simple and not overloaded with controls.
Re: Low return water temp protection methods
Close, one of the pumps would need to turn off when boiler return is below 130. It could be the injection loop pump or the boiler pump.
The primary loop is always the loop that has the expansion tank connectd to it. I think the distribution loop, up top, with the zone pumps is the primary loop?
hot_rod