In-floor heating advice

[joeblack5]

Thank you Dick,
So in your diagram the hot water comes out of the bottom.
I was thrown off by the manifold /pump picture showing the individual pump outlets.
Then the 154-185F water goes thru the floor heating Pex? The heat get tempered and distributed because the floor on top of the heating system.

In our home wood floor heating we run up to 140F. I have concrete slab floor heating in our workshop but those temperatures need to stay below 120F.

With the engine on can the floor get water in the 200F range?

How soft does the pex get with the 185F?

I looked at several styles aluminum plates. The omega style seems to give the most contact area. Do you think that that is beneficial enough to warrant the extra cost?

Thank you ,J

[somewhereinusa]

No, it's a loop the only way the pump would make pressure is if you were to put a valve in the loop. Any pressure is made by the water expanding as it heats. You can run the pump all day with the boiler off and make no pressure. You need a restriction to make pressure.

[Robin97396]

I may have missed this, but how many loops are you talking about? Do you actually heat by zones with the ability to shut off certain areas?

[Jolly Roger bus 223]

In the commercial closed loop systems like radiant flooring or solar water systems they use a special pump set up just for flushing and filling the systems to get all of the air out.
I can draw a sketch of the ones we make at work to use when we need one.
We call them flush carts and it's a simple design that works well for its purpose.

[somewhereinusa]

special pump set up just for flushing and filling the systems to get all of the air out

I used a cheap sprayer pump from Tractor Supply, one end in a bucket the other into a T I put into the main loop, works good for getting the coolant in. I also wired the pump in the boiler with a toggle switch so I could use it to help circulate.

how many loops are you talking about? Do you actually heat by zones with the ability to shut off certain areas?

I have four loops, three controlled by thermostat the fourth by switches on the dash. I don't actually shut off an area, just turn on the pump that supplies hot water to that loop.



This is the manifold and pumps for the heating system. The copper pipe on the right of the supply manifold is in the main loop, the thermostats turn the pump on or off. The lower manifold is the return at the end of each loop, again the large copper pipe is in the main loop.
Each of the water/air heaters has a fan. There is a sensor on each fan so that it won't come on if the water in the loop isn't warm enough so they won't blow cold air. There is also a manual switch for each fan. It works really well, when temperature of thermostat is attained the loop pump will turn off, when the water in that loop cools the fan will also shut off.

In practice from a cold start, I start the boiler and turn up the thermostats and turn on all of the blowers. From 0 it takes about an hour to get up to 68 degrees or so. When it's nice and cumfy I turn off the blowers and floor maintains heat pretty well. If a room seems cold I simply turn on the blower in that room.

[Robin97396]

You make it sound so simple.

[Jolly Roger bus 223]

For the commercial setup we use a single pump and flush each run separately using a piece of 8" PVC pipe. Strapped to the back of a push cart so the cart with the pump setting on the cart and the coolant/glycol jugs can be stacked on top for carrying everything. Of course it can be scaled down
More time consuming but on a larger scale you know which zone to question if it takes longer to get the air out than the others.
The idea of the pipe or bucket is the pump sucks from the bottom of the bucket and the pump return is stuck down into the top of the fluid and you maintain the level of fluid in the bucket a couple of inches above the return line until you have NO bubbles or loss of fluid.
Shutoff valves can be your best friend even if you don't think you need them right now.
Not trying to take away from what somewhere in the USA did or his advice.
It looks like somewhere used his final set up and added extra fittings to flush and fill originally and will be there if he has a problem later.
I have been told? I am the king for adding at a minimum P&T taps or actual pressure gauges and thermometers on each run. But if you have ever had to trouble shoot someone else's work then you want/ need to know what each loop is doing instead of starting from scratch?
The least complicated you keep your system in my mind means the less you have to worry about.
For me?
If I build it then I know where every nut,bolt,screw,pipe fitting,wire nut is. And I will not leave a single one where ther is No access to work on it later.

[Robin97396]

You mean like not putting a webasto inside a sealed box? I'm still trying to figure that one out.