Boilermate fe160 dhw but no heating

Hello all,

I have an old boilermate fe160, paired with a baxi system boiler that was installed 4 years ago along with drayton wireless thermostat.
At the time of the installation i also got the installer to renew the pumps and later renewed the mixer valve, did a descale and installed a water softener.

A couple of days ago i noticed that while DHW is available as usual, but the heating is not getting on.
When looked closely, even when i set the thermostat to manual, which would normally start the CH pump, the CH pump is not responding.

Any ideas on what would be wrong or troubleshoot?

Note, I have already changed the CH pump, so the pump is fine.

Cheers,
G

Boilermate II ?
If so check the pump drive board.
After checking if there is a supply at the CH pump.
With the timer on
And the room stat on.
If no supply at the pump check for supply at room stat.
If no supply at room stat check supply at timer.
And the pump drive board.
Mike

Hello Mike,

I think it is an older(?) model. There is no reference to "II". Just a handwritten FE160...

The pump does not get any power when wireless thermostat sends the signal.

I have the feeling it is the capacitor inside the Drayton Digistat SCR wireless receiver (apparently a common fault with that part). Part ordered, expected tomorrow so will see if that sorts it out.

In the meanwhile DHW stopped coming out... Not sure if mixer valve decided to kick the bucket as well!
While on the mixer valve... Do you know of a reason why there is evidence of scale build up on the valve connection (seems like a slow leak)? That is on the outside of the valve. I installed and adjusted a water softener at the mains and descaled the DHW side of the system prior to the installation of the mixer valve about 2 years ago...

Cheers
G

Hello again,

Just an additional bit of info, just tested the water hardness and it is down to 0ppm, so the water softener seems to be working.

Cheers,
G

Well if the unit is hot.
Run the hot water.
If after 5 litres or more it then goes cold then it would coil / descale.
But as you have a water softener fitted I would say mixer valve.
If the unit is NOT fully hot then you would get none.
Also check unit is full.
Look through post on BM II's that has been covered.
If it is a round unit.
It is Boilermate II or III there were older ones which only had one PCB.
Mike

Hi Mike,

The only PCB I can see, once the cover is removed, is the delay timer. There's nothing else. The mechanical clock is a Randall 103. And it is a round unit.

I know it sounds daft, but, how do you check if the unit is full?

I have looked at the top up cistern and there is enough water, covering the expansion pipe by about 2-3 inches.

Thanks,
G

Old one then.
Hose on unit
Open drain off.
Waiter level should go down in top tank.
If it does not stop.
If vent is blocked as well as cold feed the unit could implode.
Don't overfill the top tank.
Mike

Hello Mike,

Thanks for the tips.
There are 4 pipes in the cistern. 1) is for the fresh top up water, not blocked. 2) overflow, when the level in the cictern goes over a point, not blocked. 3) another pipe where i noticed a tiny bit of water flowing into the cistern just when the boiler return pump stopped, so not blocked. 4) the cold feed, not sure if blocked or not.

My plan is to:
- tease the 4th pipe with a thin enough waste pipe unblocking wire thingy.
- drain the tank
- Clean all the muck that has collected over the years in the cistern
- put a couple of litres of sentinel x400 using a hose or funnel through the 4th pipe and keep it going for a week or two.
- drain full system
- refill system and adding 3-4 litres of inhibitor

is the above sensible? Is there anything else to look out for?

Regards,
G

Hi Mike,

I forgot to ask, is the 4th pipe above going straight toards the bottom of the tank? Or is it like a coil?
Any idea of how long is that pipe?

At the moment the water is about 2-3 inches above the opening of pipe 4, and it is jut warm. Would you expect that water to be hot to the touch or just warm?

Cheers,
G

Put a hose on the unit or a rad etc.
Start draining, if the water level in the top tank goes down great.
Carry on until top tank empty (water off )
Then drain at least 10 litres more out.
Turn off drain, put in cleaner and run for a week or so.

If you do the above and water in top tank does not go down.
STOP
As you will be draining the unit.

You can remove top tank (some old ones were built on and could not be removed)
Then do what you said.
I have posted on here ref cleaning etc.
Try finding that and it will help.
Mike