boiler feeding pool and underfloor heating

[knight1]

I have to wire up an existing boiler, which currently heats a pool, to also feed an underfloor heating system, with 2 new motorised valves (for the underfloor heating flow and the pool heating flow)

I'm thinking I need a relay just on the two feeds to the boiler. Could anyone advise which type of relay. Any obvious or hidden problems I might find?

 

[ashrow]

With out listing loads of questions to answer!! you could use a 2 channel or even 3 channel programmer to operate the motorised valves, no normal need for relays.
If you need more info let me know.

Ash

 

[sparks1234]

Easy, whatever normally turns the boiler on should be used to open the valve, the valve also has a microswitch in it which turns the boiler on, same thing for the underfloor heating as well.
I would say though that normally the underfloor heating systems normally run at a lower temperature and also reuses the return water from the floor, this often comes with a manifold and actuator heads etc

 

[thepurple1]

If the underfloor heating is under a concrete slab, The boiler Flow temperature has the be limited to 55 degrees C other wise it will crack the slab. Some companies recommend turning the temprature up only 2 degrees per day untill the max is reached.
A good boiler controller would be a Satchwell DC1100 you will need to buy the sensors to go with it, the controller has outputs for valves.

 

[knight1]

The valve for the pool side of the flow will be opened by the existing pool control gear (aqua track I think)

The problem I thought I would have was that if the new feed to the boiler was calling for heat when the pool was not, then the pool control gear would be livened up from the boiler end.

 

[sparks1234]

The valve for the pool side of the flow will be opened by the existing pool control gear (aqua track I think)

The problem I thought I would have was that if the new feed to the boiler was calling for heat when the pool was not, then the pool control gear would be livened up from the boiler end.

Thats why you have the valves

 

[knight1]

Thats why you have the valves

so are you saying that if the underfloor heating is calling for heat, the pool heating control switchgear will not liven up from the boiler end and the valve for the pool flow will not open up? and therfore no need for a relay to separate the two feeds to the boiler?

 

[sparks1234]

so are you saying that if the underfloor heating is calling for heat, the pool heating control switchgear will not liven up from the boiler end and the valve for the pool flow will not open up? and therfore no need for a relay to separate the two feeds to the boiler?

Exactly

The return from your thermostats open and close the valves and then turn a microswitch on, all the microswitches of the valves have a feed to them so when valves open the relevent microswitch turns the boiler on, if you google S-plan then you may find a diagram but please remember the temps under the floor

 

[knight1]

Exactly

The return from your thermostats open and close the valves and then turn a microswitch on, all the microswitches of the valves have a feed to them so when valves open the relevent microswitch turns the boiler on, if you google S-plan then you may find a diagram but please remember the temps under the floor

Ok excellent thanks! I will check that out.

I am concerned about the floor temp. I'll have to pass that concern to the plumber/builders though I think. The pool stat is set to 30degC, however this is on the pool water side (after a heat exchanger) The stat on the flow to it is set to 55degC! I'm getting off the electrical subject now though! Unless you have any suggestions regarding this side?

 

[thepurple1]

Your client could employ a controls specialist to control the system. They could design a panel to control the system and make it efficient with a controls package such as Trend. look on there website for system houses across the U.K

https://www.trendcontrols.com/splashhandlers/index.html