3 votes
Accepted

How to install hydronic radiant heat over concrete slab

From Radiant Engineering, thanks for discussing our ThermoFin U product. The preferred method is to install the plates with the fins down. For a ThermoFin U installation on concrete, you would build a ...
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2 votes

How to install hydronic radiant heat over concrete slab

assuming you are going to put a finished floor over top of all of this, you are going to have to add another layer on top of the radiators to subfloor it. this is going to add another 1/2" or so, 5/8"...
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2 votes

Anyone installed a hot water coil in their HVAC ductwork to increase heat pump efficiency?

Better idea: flip things on their head You need hot water to run a hydronic heating coil efficiently, far hotter than you'd ever set your water heater to (water heaters struggle to reach 180°F ...
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2 votes

What are normally-open hydronic zone valves used for?

Choice of normally open or normally closed for a valve actuator is part of the overall controls design process, part of which is considering safety/protective functions. As an example, consider a ...
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2 votes
Accepted

Boiler Valve Corrosion

1) Is there any purpose for this valve other than for removing the pressure gauge? NO, the valve is only there for isolation of the gauge. Gauges like that have a high failure rate (for various ...
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  • 33.5k
2 votes

Can’t shut off power to heat-only (hydronic baseboard) thermostat

The reason you need to cut off power when replacing a thermostat is to prevent the wires from touching each other in the process of disconnecting and reconnecting all of them. Assuming it is using ...
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  • 26.6k
2 votes

Can I replace hydronic water boiler return pipes with pex?

Here in Italy pex is widely used for new heating system (both radiators and underfloor), just check the maximum allowed temperature is high enough (I'd say over 120°C) and you could use it for both ...
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  • 2,099
2 votes
Accepted

Home Heating Efficiency

If your numbers are accurate (that seems like a shockingly low price per therm for 2020): 10.57 cents buys you 13,989.2 BTU at a COP of 4.1 in the heat pump. 14.14 cents buys you 96,700 btu in the ...
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  • 137k
2 votes

Is this typical for how hot water heating loops are plumbed?

Yes, that is how modern hydronic heating systems are commonly set up. The main pipes are called the "primary loop" and each set of smaller piping to the radiators is called a "secondary ...
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  • 2,451
2 votes
Accepted

Updating baseboard radiator

Can't tell from looking at the picture you posted but it looks like a finned tube hot water baseboard unit. Do you heat your house with a hot water boiler and if not can you elaborate. If I am right ...
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  • 12.1k
1 vote

Where Can I connect my C-wire on A Hot Water (Hydronic) Heating System?

Nowhere in there. that's a DC circuit and a "C" wire is an AC thing. you'll need to use an auxillary power supply to run your smart thermostat.
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  • 13.7k
1 vote
Accepted

How impactful will it be to lose 7' of radiant heat pipe in a room?

Maybe I am missing something here but the entire loop will still be in the room so there will be heat in the wall And the floor with a longer loop. but my concern would be air trapped in this loop ...
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  • 98.2k
1 vote
Accepted

Can I replace hydronic water boiler return pipes with pex?

I don't have any first hand experience, but I don't think there's anything wrong with using PEX for a hot waater heating system. I base this on two recent observaations. 1) A new $million+ house I ...
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  • 4,059
1 vote
Accepted

New thermostat for hydronic heating, no wiring labels, 3 wires

As I mentioned in the comments, I was able to get the correct wiring by referencing an identical heating set up. It is: Red = R/H, jumpered to R/C Blue = G Yellow = W/E
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  • 121
1 vote

New thermostat for hydronic heating, no wiring labels, 3 wires

You say, "the fan would come on with a manual switch". Do you mean the "fan" switch on the old thermostat? Or a line voltage switch elsewhere, like on the fan itself? Normal T-stat wiring is 24v ...
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1 vote

How do I purge the air from a hot water furnace with zones

Well... the way that my father does it is that he isolates the zone from the other zones by shutting off the manual cutoffs. Then attaches a pump to the drain cock on both sides of the zone, and runs ...
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  • 4,243
1 vote

Most efficient way to improve my house's heating

Replacing the windows with modern double-paned isn't worth the cost; they're not that much better. However, I would recommend looking around for gaps around the windows where the putty stuff has dried ...
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  • 2,452
1 vote

Use CLR to clean stuck bleeder valve

A property piped boiler system would include a dirt separator which helps to reduce the amount of dissolved solids in the system. Inhibitors can be used to improve water quality as well. Softened ...
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  • 6,106
1 vote

New Thermostat Won't Engage Plinth Heating in Kitchen Island

Stupid me. The fan has a delay of a few minutes after the thermostat calls for heat. I set it to gas and called for heat and waited 10 or so minutes and the fan came on.
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  • 171
1 vote
Accepted

What's the effect of introducing bends into a primary-secondary heating loop?

That is actually a very good system you are proposing. My only reservation is that the cost will be excessive for only 2 apartments or zones. This is a new twist for me on a primary/secondary piping ...
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  • 12.1k
1 vote

cannot get last radiator on the line to heat up

The water that is being vented or bled out when you open the vent could be coming up either the supply or the return line. You could freeze one line and not the other. Is the circulating pump for the ...
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  • 12.1k
1 vote

What are normally-open hydronic zone valves used for?

I have used these N/O valves on a system that had a wood/coal boiler as a back up heating system so if properly piped could be used during periods of "power outages" to yield gravity flow and give ...
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  • 12.1k
1 vote

Difference between geothermal and regular hydronic zone valves

This comment pertains specifically to Taco valves, it may or may not be true of other valves intended for geothermal applications. Not all geo systems are open loop. [The geothermal valve] is made ...
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  • 4,974
1 vote

Difference between geothermal and regular hydronic zone valves

There may be other differences as well but the geothermal valve is designed for a higher head pressure. The standard hydronic system is built around reduced pressure. The geothermal valve is expected ...
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  • 6,725
1 vote

Rattling sound from heating pipes

A lot of radiators on hot water heat systems, if not, should have what is called a coin vent. These are located at the high points of each radiator. If you do not have these, you need to have them ...
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1 vote

Bosch Heat Pump + Hydronic Coil?

Heat pump + hydronics is a fantastic combo, provided you can get an air handler that supports it While you are correct that the combination of a heat pump with hydronic backup heat is uncommon, it is ...
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1 vote
Accepted

Hydronic kickspace heater on same zone as cast iron radiators?

You can mix a kick-space heater with cast iron radiators in the same zone but it is not recommended. My choice would be a "Beacon Morris". It comes in 3 models (sizes), and It has a built in ...
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  • 12.1k
1 vote

pressure in boiler getting too high

Do you have an automatic fill valve? Is there a manual valve in line with it? Try closing the manual valve if there is one. If that solves your problem, adjust and/or replace the automatic fill valve. ...
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  • 137k
1 vote

Hydronic heat radiators not used for long time - should they be drained?

It is better to keep a hot water hydronic heating system full of water all the time. This keeps air out, and prevents the inside of the radiators from rusting (assuming these are traditional cast iron ...
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  • 8,017
1 vote
Accepted

Can I run my hydronic circulator off an appliance cord in order to use it to purge air?

For those who are interested in doing this:, I simplified the wiring diagram as illustrated below. I cut the 120v lead to the circulator relay and wired it to a terminal block. From that terminal ...
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  • 4,243

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