Two Switched fused spurs for oil boiler and Hive thermostat.

Sponsored Links
“Better”? It’s essential. One switch to isolate the whole heating system. That’s the rule. Plumbers are at risk. And we don’t want to lose any of them.…
Pfffft Try complying with that across multiple floors/buildings.
 
Do you think he is not still reading and posting on this forum?
If he is 'still posting', under some guise, he is being remarkably restrained, to the point of 'being no problem' (particularly given the thread I recently started!) :)

Kind Regards, John
 
Sponsored Links
Pfffft Try complying with that across multiple floors/buildings.
I do see your point, my system has 10 supplies, however 9 of them are from pairs of AA batteries. We often fit a 3 amp fuse in plug or FCU but this then goes to the boiler which also has fuses built in, where one is using a mains supplied thermostat one must ensure that thermostat can't end up by-passing the boilers built in fuses, so the FCU feeds boiler then the boiler feeds the thermostat,

In my case the boiler FCU is battery backed, so clearly the thermostat must be fed from that FCU or the boiler would still fail to work in a power cut. But the original wiring there was a FCU on the middle floor going to a programmer which then went to the lower floor where the boiler is, now the FCU is on the lower floor and the cables to the middle floor carry 12 volt to power the Nest Gen 3 thermostat.

I do have a problem with DHW, there is no tank thermostat, and no way to turn off the DHW without also turning off central heating. I was considering fitting cables to the cistern so in the summer I can use oil for DHW, but now have solar panels with an iboost+ so in summer DHW will now be electric in the summer.

But a heating system one hopes is designed not just thrown together, and if one can get a pipe to a floor, one can also get a cable to the floor, also there is the option of using wireless devices.

The fuse can come as 1, 2, 3, 5, 7, 10 or 13 amp, but 3 and 13 amp are the preferred sizes, so most items state either 3 or 13 amp to be used, as to inrush yes it may trip a 3 amp MCB, but unlikely to cause a fuse to blow. With a 3 amp fuse worse case scenario is it blows, so fit a 3 amp, and see if it blows, I would think very unlikely.
Plumbers are at risk.
Do we still have plumbers? I suppose organ tuners would be classed as plumbers, since they still use lead, but since a plumber is a worker of lead, would not think many left, suppose there must be some who can still repair a roof?
 
Morning, if i didn't just want to stick it all on a 5a fuse could i go ...

MCB to DP Switch to an unswitched 3a spur and an unswitched 5a spur?
The oil boiler then has its specified 5a fuse and the hive receiver its 3a fuse.
 
Do we still have plumbers? I suppose organ tuners would be classed as plumbers, since they still use lead, but since a plumber is a worker of lead, would not think many left, suppose there must be some who can still repair a roof?

Lead working, was something I was taught, on cables, and I quite enjoyed the skill it needed, to get it just at the right temperature to work, without melting it.
 
Morning, if i didn't just want to stick it all on a 5a fuse could i go ...

MCB to DP Switch to an unswitched 3a spur and an unswitched 5a spur?
The oil boiler then has its specified 5a fuse and the hive receiver its 3a fuse.
Yes. (my preference) is to have the single switch to isolate both. Then there’s no confusion. So

Fit a switched FCU with 5A fuse. This will be the isolator switch. The output of this feeds the boiler and also feeds an unswitched FCU that has a 3A fuse to power the Hive.

If you want to go fancy then fit a grid plate with a DP switch and two fuse modules!
 
Yes. (my preference) is to have the single switch to isolate both. Then there’s no confusion. So

Fit a switched FCU with 5A fuse. This will be the isolator switch. The output of this feeds the boiler and also feeds an unswitched FCU that has a 3A fuse to power the Hive.

If you want to go fancy then fit a grid plate with a DP switch and two fuse modules!
Perfect thanks, that makes total sense
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top