I cannot speak from experience, only recent advice from several sources to be considered as expert. Tarm offers two systems for boiler loading, one is a Termovar loading unit which a similar to the laddomat. The other is a Termovar loading valve, coupled with a dedicated pump. They recommend the second option, as the pump would likely need replacing at some point. Mark at ahona steered me away from the laddomat for my EKO 40, indicating that it could not pump enough gpm for the size boiler and storage I have. I think he said the maximum was 13 gpm with very little head. I decided to go with a diverter (loading valve) by Danfoss and a dedicated pump. The valve begins allowing return water from the system when boiler water is up to 140 degrees. I believe the laddomat goes for somewhere around $270. A diverter valve and a Taco 007 can be had for around $210. Piping is virtually the same.
Hey thanks, interesting the guy said the Laddomat was too small for a 40. I have a 60. I was my desition though to use it, I blame myself. I have a termovar valve I could switch to and a 011 Taco pump, I cant remember the GPM of it.
I cannot speak from experience, only recent advice from several sources to be considered as expert. Tarm offers two systems for boiler loading, one is a Termovar loading unit which a similar to the laddomat. The other is a Termovar loading valve, coupled with a dedicated pump. They recommend the second option, as the pump would likely need replacing at some point. Mark at ahona steered me away from the laddomat for my EKO 40, indicating that it could not pump enough gpm for the size boiler and storage I have. I think he said the maximum was 13 gpm with very little head. I decided to go with a diverter (loading valve) by Danfoss and a dedicated pump. The valve begins allowing return water from the system when boiler water is up to 140 degrees. I believe the laddomat goes for somewhere around $270. A diverter valve and a Taco 007 can be had for around $210. Piping is virtually the same.
I cannot speak from experience, only recent advice from several sources to be considered as expert. Tarm offers two systems for boiler loading, one is a Termovar loading unit which a similar to the laddomat. The other is a Termovar loading valve, coupled with a dedicated pump. They recommend the second option, as the pump would likely need replacing at some point. Mark at ahona steered me away from the laddomat for my EKO 40, indicating that it could not pump enough gpm for the size boiler and storage I have. I think he said the maximum was 13 gpm with very little head. I decided to go with a diverter (loading valve) by Danfoss and a dedicated pump. The valve begins allowing return water from the system when boiler water is up to 140 degrees. I believe the laddomat goes for somewhere around $270. A diverter valve and a Taco 007 can be had for around $210. Piping is virtually the same.
Can you post a sketch of how you have that piped into the system? I’m curious is all. Thanks.
Plenty of pump on the laddomat, a Wilo Star I believe? I suspect the pressure drop through the thermostatic valve and all that porting gobbles up some of the circs fizz and drops the gpm off.
Thermostatics can be a tough valve to get a lot of flow through.
Over the years Heatway and Watts radiant have experimented with many brands and styles. They had some fairly high GPM models, but they wouldn’t track, and hold the temperature very well.
Paxton and Thermic have some fairly good ones for return protection. The Thermic 1-1/2” has a Cv of 27 (Cv is the gallons per minute at a 1 psi drop)
For us who don’t have the cooling coil in the top of the eco, the laddomat will when properly installed also funtion as a power failure safety through a natural flow when hooked close to a buffer tank. This feature will not work through a mixer or other thermostatic valve as far as I know.
I have the unit in my system, just no buffer at this time. It is on it’s way by means of an old electric water heater tank.
If you’re looking to just maintain return water temperature back to your your boiler,
a better & cheaper way would be to use a modulating 2-way valve. This would require a connection between your supply & return piping just like any loading valve but the pipe size could much smaller, 1/2 to 3/4”. You’d put the valves sensor on the return piping side, dial the valve to the temperature you want to maintain, the modulating valve & your boiler circulator will do the rest. You wouldn’t need a seperate circulator or relay, just a 24v connection to the valve.
Another good method, solar guy. I’m wondering what brand you use and the cost for the valve, operator, sensors and 24V transformer?
Does a 1/2 or 3/4 line move enough GPM to protect a 40 or 60K bolier connected to a radiant slab, for instance.
Burnham has always shown a boiler bypass piping or pump in their “Heating Helper” booklet. But it doesn’t have any temperature sensing ability. Probably fine for low to medium mass systems, but cold concrete slabs connected to boilers cry out for better return temperature protection, in my mind. Like the method you describe.
All in all the Laddomat is a clever design considering all the benefits. I tried to get Zenon to part with one to put on my test bench and test flow rates and capacities. In the correct application, with the correct circ it could be the system pump, bypass temperature protection, and power off dump zone control.
The valve I’m thinking about is made by Taco, model number escapes me at the moment..
If you look at Master’s pic, the valve would go where the bypass is located, the sensor on the return piping near the boiler circulator. The valve is around 200, a transformer, 20.
A 1/2 or 3/4 valve would offer adequate low water return temp protection for any residential application.
I’m just not a big fan of mechanical thermal devices, sooner or later they crud up & fail.
The valve I’m thinking about is made by Taco, model number escapes me at the moment..
If you look at Master’s pic, the valve would go where the bypass is located, the sensor on the return piping near the boiler circulator. The valve is around 200, a transformer, 20.
A 1/2 or 3/4 valve would offer adequate low water return temp protection for any residential application.
I’m just not a big fan of mechanical thermal devices, sooner or later they crud up & fail.
Have a good Sunday!
I lean the opposite way on system component selection, especially for alternate energy system. I prefer non electro-mechanical devices for dependability. A 3 way thermostatic is basically a wax cartridge, a spring and a washer and seat. really very little to fail. Good system fluid with a corrosion inhibitor should protect those valves for decades.
Heck I’d like to design a gravity powered hydronic distribution system. Zero pumps, zone valves, controls, etc. With the 2” taps on those Euro boilers it is do-able.
Our friend Larry W from another list has a gravity fed radiant system in his home in CA. Mainly solar powered, a small pv backup pump for solar harvest. I’d like to visit that home someday.
I had a gravity system in an old house up in the Adirondacks that I connected a combination wood/oil boiler to. With the wood, there was no electricity involved. All you had to do was keep the firebox full of wood, and all the radiators in the house kept the place warm. Sometimes it would get as cold as -40 and it wasn’t uncommon for it to stay below zero for days at a time. It was great when the power went out, which it did all the time up there. The guy I sold the house to still uses it that way.
