Baxi Boiler Pressure Switch 5114748 Replacement Part

This Baxi pressure switch monitors system water pressure and helps the boiler run safely by confirming there’s enough pressure in the sealed system. If it fails, you may get low-pressure lockouts, intermittent firing, or heating/hot water cutting out even after topping up, replacing with the correct switch is a reliable fix that restores stable operation and reduces nuisance shutdowns.

Compatibility :

• Baxi 600/800: 624, 630, 636, 818, 824, 825, 830, 836
• Baxi 105: 105 HE A Instant
• Baxi Duo-Tec HE: 24, 28, 33, 40
• Baxi Duo-Tec HE A: 24 (After Serial No. BTG0815 Issue 9), 24 (Before Serial No. BTG0815 Issue 9), 28 HE A (After Serial No. CAC0929 Issue 9), 28 HE A (Before Serial No.CAC0929 Issue 9), 33 HE A (After Serial No. BTH1112 Issue 9), 33 HE A (Before Serial No. BTH1112 Issue 8), 40 HE A (Issue 8)
• Baxi Duo-Tec Combi ErP 24 (Serial No. Ending AC / BC / CC / DC)
• Baxi Duo-Tec Combi ErP 28 (Serial No. Ending AC / BC / CC / DC)
• Baxi Duo-Tec Combi ErP 33 (Serial No. Ending AC / BC / CC / DC)
• Baxi Duo-Tec Combi ErP 40 (Serial No. Ending AC / BC / CC / DC)
• Baxi HE System: 15, 18, 24 (After Serial No. BTF 0932), 24 (Before Serial No. BTF 0932), 28 (After Serial No. CAB 1112), 28 (Before Serial No. CAB 1112), 32
• Baxi Megaflo HE A: 15, 18, 24, 28, 32
• Baxi System ErP 15 (Serial No. Ending IN AC / IN BC / IN CC)
• Baxi System ErP 18 (Serial No. Ending IN AC / IN BC / IN CC)
• Baxi System ErP 24 (Serial No. Ending IN AC / IN BC / IN CC)
• Baxi System ErP 28 (Serial No. Ending IN AC / IN BC / IN CC)
• Baxi System ErP 32 (Serial No. Ending IN AC / IN BC / IN CC)
• Baxi Combi HE: 24, 28, 33
• Baxi Platinum Combi HE: 24, 28, 33, 40
• Baxi Platinum Combi HE A 24 (After Serial No. BMY0815 Issue 6), 24 (Before Serial No. BMY0815 Issue 6)
• Baxi Platinum Combi HE A 28 (After Serial No. BNC0932 Issue 7), 28 (Before Serial No. BNC0932 Issue 7)
• Baxi Platinum Combi HE A 33 (After Serial No. BNE1112 Issue 5), 33 (Before Serial No. BNE1112 Issue 6)
• Baxi Platinum Combi HE A 40 (Issue 4)
• Baxi Combi ErP 24 (Serial No. Ending CC / DC / EC / IN AC / IN BC)
• Baxi Combi ErP 28 (Serial No. Ending CC / DC / EC / IN AC / IN BC)
• Baxi Combi ErP 33 (Serial No. Ending CC / DC / EC / IN AC / IN BC)
• Baxi Combi ErP 40 (Serial No. Ending CC / DC / EC / IN AC / IN BC)

Important fitting advice

We recommend that all parts are fitted by a fully qualified Gas Safe registered engineer. If you need help confirming the right part, contact us our team has 10+ years of boiler spares knowledge and friendly chat support to help you quickly.

Delivery

At Boiler Spares Hub, we dispatch orders within 1 working day (Monday-Friday). Orders placed outside working days will be dispatched on the next working day. For delivery options available for this product, please add it to your basket or check our delivery options page.

Returns

We accept 30-day returns. Returns must be in an unopened, sealed box. If we find the item has been used or installation was attempted, we may refuse the return.

Frequently Asked Questions (FAQ’s)

1. What does a baxi boiler pressure switch do?
It checks system pressure and signals the boiler it’s safe to run (helps prevent firing with low water pressure).

2. Common symptoms of a faulty pressure switch?
Boiler cutting out, low-pressure related lockouts, intermittent heating/hot water, or it won’t fire even when pressure looks ok.

3. Is this the same as a pressure relief valve (PRV)?
No-PRV releases excess pressure; the pressure switch is an electrical safety/control part that senses pressure.

4. Do serial-number variants matter?
Yes for some models (you’ll see “before/after” serial notes). Match your boiler model/serial details to the series list.

5. Installation advice?
Best fitted by a qualified heating engineer (sealed system component + electrical connections).