Boilermate 2000 hot water operation

Hello All,
1. I've just moved to the house with Boilermate 2000 + mechanical clock. I need advice from experienced boiler men about hot water operation (my electronics/electric knowledge is not enough for it). I’m not happy that my hot water tank kept all day supplied with hot water from boiler because we are at home using hot water only max 6 hours a day and not much. Reading manual for the Boilermate 2000 I found that it is possible to connect 2-channel digital clock to control not only heating but hot water(HW) as well. Am I right that if I buy any 2-channel timer I will need to disconnect permanent link between pins 21-22 and connect HW timer output to pin 22?
2. Question regarding HW temperature regulation. I’ve seen on this forum that the answer on this question is “impossible”. I’m pretty sure that thermostat for HW was removed from early versions just to make system simpler and cheaper and it was replaced by sensor so that P.C.B does logic for it. In this case must be a way to set threshold for HW on P.C.B. unless it is programmed in microcontroller for ever.

Thanks in advance,
Alex

Hi Alex,

Having has a scan throught the book I agree, you are right. The HW CAN be controlled by a programmer as well as the CH, specifically to stop the boiler from firing at night. Useful!

Bad news on the HW temperature question though. I agree it must be configured in the programming but I don't know of any way to change it. It must be possible, but it is undocumented. Another approach would be to fit a thermostatic blender valve to the output to mix in a little cold, as fitted to the Boilermate II and III.

Cheers, Mike

Hi Mike,

Thanks for the answers. I ordered and connected 2-channel timer and it works fine!

Alex

I have the same issue. Where would I get a compatible 2 channel timer from ?

auroan wrote:I have the same issue. Where would I get a compatible 2 channel timer from ?

I bought SALUS EP200
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=400134105685#ht_1354wt_699
very cheap for the given functionality. Easy to use, I'm happy.

Excellent, many thanks. Was it easy to wire in ?

auroan wrote:Excellent, many thanks. Was it easy to wire in ?

Very easy. One thing I noticed, if temperature of HW is below low level(being off for half a day for example) then if HW is still off you can't switch on CH. You need to switch on HW first to get temperature to the level then CH will be allowed to be on. May be I don't understand everything. I will update information here if I find out something new.

The timer has arrived and looks/feels quite well made for something costing £20.

I've been looking at the wireing diag. and it does indeed look like a simple job. Below is a snapshot of the area in question.... circled in blue is the reason why the hot water is on all the bloody time !!

Great... to top it all off both the HW temp sensors are knacked. Any body know a supplier for the HW and PHE return temp sensors ?

http://www.segel.co.uk/
Mike ( Norwich)

Excellent, cheers

I have just bought a controller as suggested, so just to be sure before I fit, the only change I need to make in the BM2000 is to remove the link between 21 & 22 and remove the cable from 21 and fit it into 22. Then sit back and think of all the money I am now saving!!!

neilybhoy wrote:I have just bought a controller as suggested, so just to be sure before I fit, the only change I need to make in the BM2000 is to remove the link between 21 & 22 and remove the cable from 21 and fit it into 22. Then sit back and think of all the money I am now saving!!!

No, you need to remove the link between 21 & 22 and then connect HW timer output to pin 22. Pin 21 is LIVE input for the Boilermate board. Pin 21 is switch input for HotWater, pin 22 is switch input for HeaTinG. So you connect outputs from timer to pins 22 & 23. Then sit back and think about Christmas present you can buy on saved money

scorp wrote:

neilybhoy wrote:I have just bought a controller as suggested, so just to be sure before I fit, the only change I need to make in the BM2000 is to remove the link between 21 & 22 and remove the cable from 21 and fit it into 22. Then sit back and think of all the money I am now saving!!!

No, you need to remove the link between 21 & 22 and then connect HW timer output to pin 22. Pin 21 is LIVE input for the Boilermate board. Pin 21 is switch input for HotWater, pin 22 is switch input for HeaTinG. So you connect outputs from timer to pins 22 & 23. Then sit back and think about Christmas present you can buy on saved money

apologies but just to be sure I understand you correctly, I remove the link between 21 & 22, connect the HW timer output into 22 (previously in 21?) and leave the cable going into 23 alone?

neilybhoy wrote:

scorp wrote:

neilybhoy wrote:I have just bought a controller as suggested, so just to be sure before I fit, the only change I need to make in the BM2000 is to remove the link between 21 & 22 and remove the cable from 21 and fit it into 22. Then sit back and think of all the money I am now saving!!!

No, you need to remove the link between 21 & 22 and then connect HW timer output to pin 22. Pin 21 is LIVE input for the Boilermate board. Pin 21 is switch input for HotWater, pin 22 is switch input for HeaTinG. So you connect outputs from timer to pins 22 & 23. Then sit back and think about Christmas present you can buy on saved money

apologies but just to be sure I understand you correctly, I remove the link between 21 & 22, connect the HW timer output into 22 (previously in 21?) and leave the cable going into 23 alone?

Yes, but you didn't have previously HW timer connected to 21. That is Live. And the link connects Live(pin 21) to switch on HW(permanently). After reconnecting your timer will connect pin 22 to 21 but inside the timer. The same happens with pin 23. Pin 23 connected inside the timer to Live(pin 21) when HTG is on. You will need to connect pin 23 to HTG output of your new timer if your new timer has 2 channels. If you bought timer with one channel only for HW and don't want to touch old HTG timer then you need only to disconnect the link and connect timer to pin 22.

Went to make the changes only to find that my BM does not have a mechanical internal clock or switch. Can I make any changes or am I stuck with the current configuration?

neilybhoy wrote:Went to make the changes only to find that my BM does not have a mechanical internal clock or switch. Can I make any changes or am I stuck with the current configuration?

I'm not a professional boiler engineer and I haven't seen other type of connections but if you explain what you have connected to those pins then we can think what can or cannot be done

Cable connections as follows
20 no cable
21 and 22 linked together
23 has a cable connected which is the 4th core of the mains power supply
24 no cable
25 to 28 have cables connected from the room stat.

neilybhoy wrote:Cable connections as follows
20 no cable
21 and 22 linked together
23 has a cable connected which is the 4th core of the mains power supply
24 no cable
25 to 28 have cables connected from the room stat.

Ok. Most likely you don't have timer near the board. The HTG timer probably is in the other room which connects "live" to your 4th core when HTG is on. Anyway, disconnect link between 21 and 22, disconnect 4th core and isolate it. Better to find the switch connected to it otherwise you may work under the "live" on that core if HTG is on. I would switch off whole house. Then you will need 4 wires to connect your new timer. N(neutral) from timer to pin 20 on PCB, L from timer to pin 21, HW(or channel 1) from timer to pin 22, and finally HTG(or channel 2) from timer to pin 23.

Thanks for your quick response. I understand what is to be done, but I suspect that I need to run a new cable between the new 2 channel timer (downstairs in utility room) and the boilermate (upstairs) to achieve this. This could be problematic!!

The other option would be to install the new timer local to the BM but I would still need a cable to link the timer to the boiler? My boiler is situated above the timeclock, so there will be a cable between the boiler and the timeclock.

neilybhoy wrote:Thanks for your quick response. I understand what is to be done, but I suspect that I need to run a new cable between the new 2 channel timer (downstairs in utility room) and the boilermate (upstairs) to achieve this. This could be problematic!!

The other option would be to install the new timer local to the BM but I would still need a cable to link the timer to the boiler? My boiler is situated above the timeclock, so there will be a cable between the boiler and the timeclock.

Ah, I forgot that timer may be far away. Yes, you need to run cable even if the timer is local to the BM. I just used 2 standard power cables from any DIY shop (or you may find 4 wire cable ...) and put it next to BM on the wall. Can't think of any other way how to connect it downstairs having only one wire(the 4th core) from downstairs. To be honest my far future plan is to have timer to be accessible from PC but in this case I think I will need to make my own timer based on any microcontroller development board with Ethernet capability via PowerLine.....don't have time for it, now just trying to connect my Power Monitor to internet but it would be nice to control house over the internet from work.

Is it possible to rewire the existing manual clock/timer in the Boliermate 2000 to do the above?

cc8vt wrote:Is it possible to rewire the existing manual clock/timer in the Boliermate 2000 to do the above?

If you also have a roomstat wired into terminals 25-28 (these are usually extended down to the roomstat field wiring below PCB), you might be able to use the existing clock from the heating control connection to the hot water control connection then linking fitting a loop.

The existing time clock will likely go into terminal 23 and you will have a loop between 21 and 22 for permanent hot water.

Swap the connections on pins 22 and 23 to make the hot water timed, now you will get hot water only when the existing clock/ timer is switched on. The roomstat will control when you get heat.

If you don't think you're competent to check the above don't do anything!

Scorp, did you ascertain whether the hot water needed to reach temperature for the central heating to come on?