Cylinder System not running heating and water at the same time

[jea_123]

Hello,
Newly moved into a house with a mains fed cylinder system. I've never had one before and struggling to get it working.

When I turn either heating or water off at the timing unit, the other works fine. Eg, with heating off, water works and vica versa. The indicator lights are solid blue and LCD display does not flash.

However, when I try to run both together, the timing unit starts flashing. Both indicator lights and the LCD display flashes.

I've found a manual for the timing unit online under a different brand name, and it doesn't mention a flashing status.

Does this need an engineer, or am I just being an idiot with the settings?

 

[jea_123]

The manual I found for what appears to be the same timing unit under a different brand name.

 

[ShaunCorbs]

Any chance of a better picture of the pipes underneath of the boiler ?

As it should be hot water priority/ 4 pipe set up

 

[jea_123]

Hopefully better pics attached.
I presume the guy who installed it wrote the below in pencil on the wall that appears to label the pipes to the boiler. Left to right it says heat flow, cylinder flow, gas, cylinder RTN, CX RTN. It appears to match the boiler. The first pipe goes off to the heating system, second to the cylinder, 3rd has a yellow tap, 4th is connected to cylinder, 5th goes off to radiators parallel to 1st pipe.

 

[ShaunCorbs]

With the system as it is you will only have one at a time not both together best to run the hot water all day and the cylinder stat will keep it topped up if you use a bit of hot water

 

[jea_123]

With the system as it is you will only have one at a time not both together best to run the hot water all day and the cylinder stat will keep it topped up if you use a bit of hot water

I have a hive e. This asks me to leave the heating on permanently and let the thermostat control demand.

Does this mean I can't have the timer asking for both heat and water at the same time?

 

[ShaunCorbs]

Isn’t the hive e and timed room stat ?

 

[Chuck]

"However, when I try to run both together, the timing unit starts flashing. Both indicator lights and the LCD display flashes."

The simplest explanation is that the programmer has a mode that blocks CH and DHW being on simultaneously, like a 'Y-plan' system. This prevents the DHW from starving the radiators in cold weather and assumes you heat the DHW store at night when the CH is off. The flashing LEDs indicate that you are attempting to override the mutually-exclusive constraint.

This is not mentioned in the instructions you've posted, but those are not actually for your programmer so can't be relied on to describe all the features.

IMO, mutual exclusion is not usually a good idea – it's a cure that's worse than the disease.

 

[Deleted member 120897]

I have a hive e. This asks me to leave the heating on permanently and let the thermostat control demand.

Does this mean I can't have the timer asking for both heat and water at the same time?

Looks like a Nest imo.

 

[Chuck]

The simplest explanation is that...

Or, even simpler, the unit is faulty. The Sangamo "Choice PR2" instructions are available on line but 'mutual exclusion' isn't one of the options.

Sangamo have a place in Glasgow, try contacting them and see what they say the flashing behaviour means.

Contact Us

Customer Service / Sales: Tel: 01527 515 150 Email: [email protected] Address: Elite Security Product Limited, Unit 7 Target Park, Shawbank Road, Lakeside, Redditch, Worcestershire B98 8YN Office Hours: Mon-Fri 9:00-17:00 Manufacturing / Refurb & Spares Online Sales: Tel: 01475 745 131 Email...

www.sangamo.co.uk

 

[jea_456]

OP here. Had to create a separate account to log in from work.

Thanks for your advice.
I've emailed the company for their opinion.

I have a background in electronics engineering (20 years ago and not in industry).

The flashing status is odd to me. When the LED's and LCD are off in the flashing cycle, the buttons don't accept any inputs. I have to time button presses when the LCD and LED's are flashing on. That strikes me as odd, as if it were programmed behaviour, as an error signal, I can't see why the micro controller would be programmed to not accept inputs. It feels like a power issue to me. If it were a low voltage DC electronics circuit, it would make me suspicious of a power supply issue.
But it's supplied at mains voltage. And it's a very regular flashing cycle, as though deliberately timed at a set frequency.

I'll stick a meter on the supply to the unit while it's flashing and see if the power is being interrupted in time with the flashing.

Is it possible that the boiler could be interrupting the power to the control unit? There's no error message on the boiler's LCD.

 

[Basher]

The user, installation and wiring instructions/diagrams are all out there on the interweb, but I imagine wouldn't tell anything you don't already know.
It appears there is a 'backup' battery in the unit, which must now be end-of-life. I've had old programmers misbehave due to failed battery dragging the power rail down. Might be worth replacing battery, or even just removing, though the latter option means the thing loses settings whenever the power goes off!!